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BIOTECHNOLOGY (238 journals)                  1 2 | Last

Showing 1 - 200 of 238 Journals sorted alphabetically
3 Biotech     Open Access   (Followers: 8)
Advanced Biomedical Research     Open Access  
Advances in Bioscience and Biotechnology     Open Access   (Followers: 14)
Advances in Genetic Engineering & Biotechnology     Hybrid Journal   (Followers: 8)
African Journal of Biotechnology     Open Access   (Followers: 6)
Algal Research     Partially Free   (Followers: 10)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 65)
American Journal of Bioinformatics Research     Open Access   (Followers: 7)
American Journal of Polymer Science     Open Access   (Followers: 31)
Anadolu University Journal of Science and Technology : C Life Sciences and Biotechnology     Open Access  
Animal Biotechnology     Hybrid Journal   (Followers: 8)
Annales des Sciences Agronomiques     Full-text available via subscription  
Applied Biochemistry and Biotechnology     Hybrid Journal   (Followers: 43)
Applied Bioenergy     Open Access  
Applied Biosafety     Hybrid Journal  
Applied Food Biotechnology     Open Access   (Followers: 3)
Applied Microbiology and Biotechnology     Hybrid Journal   (Followers: 63)
Applied Mycology and Biotechnology     Full-text available via subscription   (Followers: 4)
Arthroplasty Today     Open Access   (Followers: 1)
Artificial Cells, Nanomedicine and Biotechnology     Hybrid Journal   (Followers: 1)
Asia Pacific Biotech News     Hybrid Journal   (Followers: 2)
Asian Journal of Biotechnology     Open Access   (Followers: 9)
Asian Pacific Journal of Tropical Biomedicine     Open Access   (Followers: 2)
Australasian Biotechnology     Full-text available via subscription   (Followers: 1)
Banat's Journal of Biotechnology     Open Access  
BBR : Biochemistry and Biotechnology Reports     Open Access   (Followers: 5)
Bio-Algorithms and Med-Systems     Hybrid Journal   (Followers: 2)
Bio-Research     Full-text available via subscription   (Followers: 3)
Bioactive Materials     Open Access   (Followers: 1)
Biocatalysis and Agricultural Biotechnology     Hybrid Journal   (Followers: 4)
Biocybernetics and Biological Engineering     Full-text available via subscription   (Followers: 5)
Bioethics UPdate     Hybrid Journal  
Biofuels     Hybrid Journal   (Followers: 11)
Biofuels Engineering     Open Access   (Followers: 1)
Biological & Pharmaceutical Bulletin     Full-text available via subscription   (Followers: 4)
Biological Cybernetics     Hybrid Journal   (Followers: 10)
Biomarkers and Genomic Medicine     Open Access   (Followers: 3)
Biomarkers in Drug Development     Partially Free   (Followers: 1)
Biomaterials Research     Open Access   (Followers: 4)
BioMed Research International     Open Access   (Followers: 4)
Biomédica     Open Access  
Biomedical and Biotechnology Research Journal     Open Access  
Biomedical Engineering Research     Open Access   (Followers: 6)
Biomedical glasses     Open Access  
Biomedical Reports     Full-text available via subscription  
BioMedicine     Open Access  
Biomedika     Open Access  
Bioprinting     Hybrid Journal   (Followers: 1)
Bioresource Technology Reports     Hybrid Journal   (Followers: 1)
Bioscience, Biotechnology, and Biochemistry     Hybrid Journal   (Followers: 21)
Biosimilars     Open Access   (Followers: 1)
Biosurface and Biotribology     Open Access  
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 2)
BioTechniques : The International Journal of Life Science Methods     Full-text available via subscription   (Followers: 28)
Biotechnologia Acta     Open Access   (Followers: 1)
Biotechnologie, Agronomie, Société et Environnement     Open Access   (Followers: 2)
Biotechnology     Open Access   (Followers: 6)
Biotechnology & Biotechnological Equipment     Open Access   (Followers: 4)
Biotechnology Advances     Hybrid Journal   (Followers: 33)
Biotechnology and Applied Biochemistry     Hybrid Journal   (Followers: 44)
Biotechnology and Bioengineering     Hybrid Journal   (Followers: 152)
Biotechnology and Bioprocess Engineering     Hybrid Journal   (Followers: 5)
Biotechnology and Genetic Engineering Reviews     Hybrid Journal   (Followers: 13)
Biotechnology and Health Sciences     Open Access   (Followers: 1)
Biotechnology and Molecular Biology Reviews     Open Access   (Followers: 2)
Biotechnology Annual Review     Full-text available via subscription   (Followers: 5)
Biotechnology for Biofuels     Open Access   (Followers: 10)
Biotechnology Frontier     Open Access   (Followers: 2)
Biotechnology Journal     Hybrid Journal   (Followers: 16)
Biotechnology Law Report     Hybrid Journal   (Followers: 4)
Biotechnology Letters     Hybrid Journal   (Followers: 34)
Biotechnology Progress     Hybrid Journal   (Followers: 40)
Biotechnology Reports     Open Access  
Biotechnology Research International     Open Access   (Followers: 1)
Biotechnology Techniques     Hybrid Journal   (Followers: 10)
Biotecnología Aplicada     Open Access  
Bioteknologi (Biotechnological Studies)     Open Access  
Biotribology     Hybrid Journal   (Followers: 1)
BMC Biotechnology     Open Access   (Followers: 16)
Cell Biology and Development     Open Access  
Chinese Journal of Agricultural Biotechnology     Full-text available via subscription   (Followers: 4)
Communications in Mathematical Biology and Neuroscience     Open Access  
Computational and Structural Biotechnology Journal     Open Access   (Followers: 2)
Computer Methods and Programs in Biomedicine     Hybrid Journal   (Followers: 8)
Contributions to Tobacco Research     Open Access   (Followers: 2)
Copernican Letters     Open Access   (Followers: 1)
Critical Reviews in Biotechnology     Hybrid Journal   (Followers: 20)
Crop Breeding and Applied Biotechnology     Open Access   (Followers: 3)
Current Bionanotechnology     Hybrid Journal  
Current Biotechnology     Hybrid Journal   (Followers: 4)
Current Opinion in Biomedical Engineering     Hybrid Journal   (Followers: 1)
Current Opinion in Biotechnology     Hybrid Journal   (Followers: 56)
Current Pharmaceutical Biotechnology     Hybrid Journal   (Followers: 9)
Current Research in Bioinformatics     Open Access   (Followers: 12)
Current Trends in Biotechnology and Chemical Research     Open Access   (Followers: 3)
Current trends in Biotechnology and Pharmacy     Open Access   (Followers: 8)
EBioMedicine     Open Access  
Electronic Journal of Biotechnology     Open Access  
Entomologia Generalis     Full-text available via subscription  
Environmental Science : Processes & Impacts     Full-text available via subscription   (Followers: 4)
Experimental Biology and Medicine     Hybrid Journal   (Followers: 3)
Folia Medica Indonesiana     Open Access  
Food Bioscience     Hybrid Journal  
Food Biotechnology     Hybrid Journal   (Followers: 9)
Food Science and Biotechnology     Hybrid Journal   (Followers: 8)
Frontiers in Bioengineering and Biotechnology     Open Access   (Followers: 6)
Frontiers in Systems Biology     Open Access   (Followers: 2)
Fungal Biology and Biotechnology     Open Access   (Followers: 2)
GM Crops and Food: Biotechnology in Agriculture and the Food Chain     Full-text available via subscription   (Followers: 1)
GSTF Journal of BioSciences     Open Access  
HAYATI Journal of Biosciences     Open Access  
Horticulture, Environment, and Biotechnology     Hybrid Journal   (Followers: 11)
IEEE Transactions on Molecular, Biological and Multi-Scale Communications     Hybrid Journal   (Followers: 1)
IET Nanobiotechnology     Hybrid Journal   (Followers: 2)
IIOAB Letters     Open Access  
IN VIVO     Full-text available via subscription   (Followers: 4)
Indian Journal of Biotechnology (IJBT)     Open Access   (Followers: 2)
Indonesia Journal of Biomedical Science     Open Access   (Followers: 2)
Indonesian Journal of Biotechnology     Open Access   (Followers: 1)
Industrial Biotechnology     Hybrid Journal   (Followers: 18)
International Biomechanics     Open Access  
International Journal of Bioinformatics Research and Applications     Hybrid Journal   (Followers: 13)
International Journal of Biomechatronics and Biomedical Robotics     Hybrid Journal   (Followers: 4)
International Journal of Biomedical Research     Open Access   (Followers: 2)
International Journal of Biotechnology     Hybrid Journal   (Followers: 5)
International Journal of Biotechnology and Molecular Biology Research     Open Access   (Followers: 3)
International Journal of Biotechnology for Wellness Industries     Partially Free   (Followers: 1)
International Journal of Environment, Agriculture and Biotechnology     Open Access   (Followers: 5)
International Journal of Functional Informatics and Personalised Medicine     Hybrid Journal   (Followers: 4)
International Journal of Medicine and Biomedical Research     Open Access   (Followers: 1)
International Journal of Nanotechnology and Molecular Computation     Full-text available via subscription   (Followers: 3)
International Journal of Radiation Biology     Hybrid Journal   (Followers: 4)
Iranian Journal of Biotechnology     Open Access  
ISABB Journal of Biotechnology and Bioinformatics     Open Access  
Italian Journal of Food Science     Open Access   (Followers: 1)
JMIR Biomedical Engineering     Open Access  
Journal of Biometrics & Biostatistics     Open Access   (Followers: 3)
Journal of Bioterrorism & Biodefense     Open Access   (Followers: 6)
Journal of Petroleum & Environmental Biotechnology     Open Access   (Followers: 1)
Journal of Advanced Therapies and Medical Innovation Sciences     Open Access  
Journal of Advances in Biotechnology     Open Access   (Followers: 5)
Journal Of Agrobiotechnology     Open Access  
Journal of Analytical & Bioanalytical Techniques     Open Access   (Followers: 7)
Journal of Animal Science and Biotechnology     Open Access   (Followers: 4)
Journal of Applied Biomedicine     Open Access   (Followers: 2)
Journal of Applied Biotechnology     Open Access   (Followers: 2)
Journal of Applied Biotechnology Reports     Open Access   (Followers: 2)
Journal of Applied Mathematics & Bioinformatics     Open Access   (Followers: 5)
Journal of Biologically Active Products from Nature     Hybrid Journal   (Followers: 1)
Journal of Biomaterials and Nanobiotechnology     Open Access   (Followers: 6)
Journal of Biomedical Photonics & Engineering     Open Access  
Journal of Biomedical Practitioners     Open Access  
Journal of Bioprocess Engineering and Biorefinery     Full-text available via subscription  
Journal of Bioprocessing & Biotechniques     Open Access  
Journal of Biosecurity, Biosafety and Biodefense Law     Hybrid Journal   (Followers: 3)
Journal of Biotechnology     Hybrid Journal   (Followers: 68)
Journal of Biotechnology and Strategic Health Research     Open Access  
Journal of Chemical and Biological Interfaces     Full-text available via subscription   (Followers: 1)
Journal of Chemical Technology & Biotechnology     Hybrid Journal   (Followers: 9)
Journal of Chitin and Chitosan Science     Full-text available via subscription  
Journal of Colloid Science and Biotechnology     Full-text available via subscription  
Journal of Commercial Biotechnology     Full-text available via subscription   (Followers: 6)
Journal of Crop Science and Biotechnology     Hybrid Journal   (Followers: 3)
Journal of Essential Oil Research     Hybrid Journal   (Followers: 2)
Journal of Experimental Biology     Full-text available via subscription   (Followers: 24)
Journal of Genetic Engineering and Biotechnology     Open Access   (Followers: 5)
Journal of Ginseng Research     Open Access  
Journal of Industrial Microbiology and Biotechnology     Hybrid Journal   (Followers: 16)
Journal of Integrative Bioinformatics     Open Access  
Journal of International Biotechnology Law     Hybrid Journal   (Followers: 3)
Journal of Medical Imaging and Health Informatics     Full-text available via subscription  
Journal of Molecular Biology and Biotechnology     Open Access  
Journal of Molecular Microbiology and Biotechnology     Full-text available via subscription   (Followers: 11)
Journal of Nano Education     Full-text available via subscription  
Journal of Nanobiotechnology     Open Access   (Followers: 4)
Journal of Nanofluids     Full-text available via subscription   (Followers: 1)
Journal of Organic and Biomolecular Simulations     Open Access  
Journal of Plant Biochemistry and Biotechnology     Hybrid Journal   (Followers: 4)
Journal of Science and Applications : Biomedicine     Open Access  
Journal of the Mechanical Behavior of Biomedical Materials     Hybrid Journal   (Followers: 11)
Journal of Trace Elements in Medicine and Biology     Hybrid Journal   (Followers: 1)
Journal of Tropical Microbiology and Biotechnology     Full-text available via subscription  
Journal of Yeast and Fungal Research     Open Access   (Followers: 1)
Marine Biotechnology     Hybrid Journal   (Followers: 4)
Messenger     Full-text available via subscription  
Metabolic Engineering Communications     Open Access   (Followers: 4)
Metalloproteinases In Medicine     Open Access  
Microalgae Biotechnology     Open Access   (Followers: 2)
Microbial Biotechnology     Open Access   (Followers: 9)
MicroMedicine     Open Access   (Followers: 3)
Molecular and Cellular Biomedical Sciences     Open Access   (Followers: 1)
Molecular Biotechnology     Hybrid Journal   (Followers: 13)
Molecular Genetics and Metabolism Reports     Open Access   (Followers: 3)
Nanobiomedicine     Open Access  
Nanobiotechnology     Hybrid Journal   (Followers: 2)
Nanomaterials and Nanotechnology     Open Access  
Nanomaterials and Tissue Regeneration     Open Access  
Nanomedicine and Nanobiology     Full-text available via subscription  
Nanomedicine Research Journal     Open Access  
Nanotechnology Reviews     Hybrid Journal   (Followers: 5)

        1 2 | Last

Journal Cover
Journal of Biotechnology
Journal Prestige (SJR): 0.929
Citation Impact (citeScore): 3
Number of Followers: 68  
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0168-1656
Published by Elsevier Homepage  [3163 journals]
  • Differential expression of microRNAs in recombinant Chinese hamster ovary
           cells treated with sodium butyrate using digital RNA counting
    • Abstract: Publication date: 10 October 2018Source: Journal of Biotechnology, Volume 283Author(s): Sung-Min Lim, Sun-Hye Park, Joo-Hyoung Lee, Sun Hong Kim, Jee Yon Kim, Jeong-Ki Min, Gyun Min Lee, Yeon-Gu Kim Sodium butyrate (NaBu) is an efficient supplement for increasing recombinant protein production in Chinese hamster ovary (CHO) cell culture. To elucidate the effects of NaBu on miRNA expression profile in recombinant CHO (rCHO) cells, differentially expressed miRNAs in NaBu-treated rCHO cells were assessed by NanoString nCounter analysis. This result showed that eight mature mouse miRNAs (let-7b, let-7d, miR-15b, miR-25, miR-27a, miR-99a, miR-125a-5p, and miR-125b-5p) were differentially expressed. Furthermore, quantitative real-time RT-PCR analysis of eight mature CHO miRNAs, annotated using a miRBase database, confirmed the transcriptomic findings. Among the potential corresponding target mRNAs for the selected mature miRNAs, seven cell growth-related target genes (e2f2, akt2, mtor, bcl-2, bim, p38α, and bmf) and five N-glycosylation-related target genes (neu1, b4galt3, gale, man1b1 and mgat4a) were selected by considering the effectiveness of NaBu on rCHO cell culture. The altered expression patterns of the 12 target mRNAs were inversely correlated with those of the selected mature miRNAs. Altogether, NanoString nCounter analysis may be useful for identifying differentially expressed miRNAs in rCHO cells.
  • Rational engineering of the shikimate and related pathways in
           Corynebacterium glutamicum for 4-hydroxybenzoate production
    • Abstract: Publication date: Available online 19 July 2018Source: Journal of BiotechnologyAuthor(s): Henry Syukur Purwanto, Mi-Sook Kang, Lenny Ferrer, Sang-Soo Han, Jin-Young Lee, Hak-Sung Kim, Jin-Ho Lee 4-Hydroxybenzoate (4HBA) is a valuable platform intermediate for the production of commodity and fine chemicals, including protocatechuate, cis,cis-muconic acid, adipic acid, terephthalic acid, phenol, vanillin, and 4-hydroxybenzyl alcohol glycoside (gastrodin). Here we describe rational engineering of the shikimate and related pathways in Corynebacterium glutamicum ATCC13032 for over-producing 4HBA. As an approach to increase the carbon flux to 4HBA, we first introduced a mutated chorismate-pyruvate lyase (CPLpr) and feedback-resistant 3-deoxy-D-arabinoheptulosonate-7-phosphate synthases encoded by ubiCpr and aroFfbr/aroGfbr, respectively, from Escherichia coli along with blockage of carbon flux to the biosynthetic pathways for aromatic amino acids and the catabolic pathway for 4HBA by deletion of the genes trpE (encoding anthranilate synthase I), csm (chorismate mutase), and pobA (4HBA hydroxylase). In particular, CPLpr less sensitive to product inhibition was incorporated into the microorganism to enhance the conversion of chorismate to 4HBA. The subsequent steps involved expression of aroE (shikimate kinase) and aroCKB in the shikimate pathway and deletion of qsuABD coding for enzymes involved in the quinate/shikimate degradation pathway. Finally, to reduce accumulation of pathway intermediates, shikimate and 3-dehydroshikimate, shikimate-resistant AroK from Methanocaldococcus jannaschii was introduced. The resulting strain was shown to produce 19.0 g/L (137.6 mM) of 4HBA with a molar yield of 9.65% after 65 h in a fed-batch fermentation. The engineered strain can also be effectively applied for the production of other products derived from the shikimate pathway.
  • Analysis of the genome sequence of plant beneficial strain
           Pseudomonas sp. RU47
    • Abstract: Publication date: Available online 18 July 2018Source: Journal of BiotechnologyAuthor(s): Nemanja Kuzmanović, Namis Eltlbany, Ding Guochun, Mohamed Baklawa, Lin Min, Lu Wei, Kornelia Smalla Pseudomonas sp. RU47 (RU47) is a rhizosphere-competent strain showing plant growth-promoting and biocontrol activities. In this study, the genome sequence of strain RU47 was obtained and phylogenetic and comparative genome analyses were performed. Multilocus sequence analysis (MLSA) coupled with the calculation of average nucleotide identity (ANI) and in silico DNA–DNA hybridization (DDH) values suggested that strain RU47 belongs to the P. koreensis group of the P. fluorescens complex, but cannot be assigned to any known Pseudomonas species. Multiple genes and operons encoding for functions that likely contribute to its previously reported high rhizosphere competence, biocontrol of Rhizoctonia solani and plant growth promotion in soils with reduced fertilization were identified. Putative genes and gene clusters for the production of hydrogen cyanide, cyclic lipopeptides, bacteriocins, siderophores, indole-3-acetic acid, spermidine, alkaline protease A, chitinase and ß-1,3-glucanase were identified, as well as loci associated with solubilization of inorganic phosphate. Several of these functions were also confirmed by in vitro testing. Distribution of putative genes and gene clusters that may contribute to the plant growth-promoting and biocontrol activities was largely similar among strains belonging to P. koreensis group, as revealed by comparative genome analysis. Data presented in this study further support the potential of RU47 for its application in agriculture and may be a valuable resource for further studies.
  • Prediction of enantioselectivity of lipase catalyzed kinetic resolution
           using umbrella sampling
    • Abstract: Publication date: Available online 18 July 2018Source: Journal of BiotechnologyAuthor(s): Ashwini C. Mathpati, Bhalchandra M. Bhanage Enantiopure intermediates are preferred for drug synthesis in pharmaceutical industry. Lipases are widely used for chiral resolution of optically active compounds based on kinetic resolution. In the kinetic resolution, two enantiomers react with different rates in presence of a chiral catalyst or reagent, resulting in obtaining one enantiomer of great excess compared to other. The enantiomeric ratio (E) is closely related to the free energy difference (ΔΔG) of the activated state of substrate enantiomers. Molecular dynamic (MD) simulations with umbrella sampling technique can be used for estimation of activation free energy change of enantiomers. In this work, lipase-catalyzed transesterification of racemic alcohols with single and double hydroxyl groups have been studied. The umbrella sampling studies have been carried out for Candida rugosa lipase and Burkholderia cepacia lipase in n-hexane. The distance between serine residue in the catalytic triad and the ligand has been considered as a reaction coordinate and various conformations have been selected for MD simulation. The E value has been estimated based on free energy change from umbrella sampling. The estimated E values are in good agreement with experimental data. The work highlights changes in lipase conformation in n-hexane, ligand-protein interaction as well as free energy curve as a function of the reaction coordinate.
  • Expression of a Zika virus antigen in microalgae: towards mucosal
           vaccine development
    • Abstract: Publication date: Available online 18 July 2018Source: Journal of BiotechnologyAuthor(s): Verónica Araceli Márquez-Escobar, Bernardo Bañuelos-Hernández, Sergio Rosales-Mendoza Zika virus (ZIKV) infection has extended rapidly all over the world in the last decades affecting humans of all ages, inducing severe illness such as the autoimmune Guillain-Barré syndrome as well as fetal neurodevelopmental defects. Despite the epidemiological importance of ZIKV, today there are no commercially available drugs or vaccines to combat or prevent this infection. Microalgae are attractive hosts to produce and deliver vaccines, with some candidates under preclinical evaluation. Herein, algae-based expression was assessed for the production of a new vaccine candidate against ZIKV called ZK. The Algevir technology was applied to express an antigenic protein called ZK comprising the B subunit of the heat labile Escherichia coli enterotoxin along with 3 epitopes from the ZIKV envelope glycoprotein. Efficient expression of the ZK antigen was achieved in Schizochytrium sp. with yields of up to 365 µg g-1 microalgae fresh weight. Upon oral administration in mice, the microalgae-made ZK protein elicited significant humoral responses at a higher magnitude to those induced upon subcutaneous immunization. The algae-made ZK vaccine represents a promising candidate to formulate attractive vaccines against ZIKV.
  • Scale-up of Continuous Multicolumn Chromatography for the Protein A
           capture step: from Bench to Clinical Manufacturing
    • Abstract: Publication date: Available online 17 July 2018Source: Journal of BiotechnologyAuthor(s): Ozan Ötes, Hendrik Flato, Daniel Vazquez Ramirez, Britta Badertscher, Marc Bisschops, Florian Capito The awareness about implementing continuous processing for biopharmaceutical products has significantly increased throughout the recent years not only at developmental scale but also for phase I supply in clinical trial manufacturing. In this study, we focused on upscaling continuous protein A chromatography from lab to pilot scale using the Cadence™ BioSMB PD and the Cadence™ BioSMB Process 80 system, respectively. Additionally, we evaluated hardware and software capability whilst running the system for 10 days non-stop using feed from a perfusion bioreactor. In terms of product quality and removal of impurities, comparable data was obtained regarding lab scale and production scale. Compared to batch mode, productivity was increased by 400 to 500%. Furthermore, the system worked accurately during the whole trial, proving its potential for the implementation into a hybrid or an end-to-end continuous process.
  • Rational engineering of ornithine decarboxylase with greater selectivity
           for ornithine over lysine through protein network analysis
    • Abstract: Publication date: Available online 17 July 2018Source: Journal of BiotechnologyAuthor(s): Eun Young Hong, Jin Young Kim, Roopali Upadhyay, Byung Jun Park, Jong Min Lee, Byung-Gee Kim Ornithine decarboxylase (ODC) converts C5 ornithine into C4 putrescine, a monomer for polyamide synthesis. However, ODC also has minor activity towards cell metabolite C6 lysine and yields C5 cadaverine. The accumulation of cadaverine in the reaction solution causes increase in the operational cost of subsequent distillation process for putrescine purification. Here, to increase ODC substrate specificity toward ornithine over lysine, molecular modelling and protein network analysis, specifically k-clique community analysis, around the substrate tunnel were performed. This resulted in a mutant with two-fold increase in substrate specificity (ornithine versus lysine) without losing its original activity towards ornithine (kcat/KM =61.5 s-1  mM-1), compared to the native enzyme. When this mutant was used for putrescine synthesis, 31.6 g/L putrescine (based on 51.5 g/L ornithine) titer was achieved, while 0.007 g/L (based on 2.57 g/L lysine) cadaverine was produced. This corresponds to four-fold decrease in cadaverine yield compared to the native ODC.
  • Extraction of value-added components from food industry based and
           agro-forest biowastes by deep eutectic solvents
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Michal Jablonský, Andrea Škulcová, Ana Malvis, Jozef Šima The scientific community, experts in technology and marketing have been seeking cost-competitive and green solvents with good dissolving capacity for the valorisation of biomass and biowaste. Along with traditional solvents and techniques, deep eutectic solvents (DESs) and their bio-analogues, natural deep eutectic solvents (NADESs) are currently emerging as a new class of promising liquid media. In this review, a comprehensive summary of recent contribution of DESs to the processing and valorisation of various kinds of plant and animal based biomass and biowaste is provided. In the field of food industry based and agro-forest waste valorisation, through treatment of the waste, by-products, and natural materials by DESs, several types of compounds, such as flavonoids and other plant phenolics, phenolic acids, stilbenes, tannins, lignans, and lignin were obtained. Extraction of algae by DESs led to isolation mainly of proteins, carbohydrates, lipids and nucleic acids. Vegetable oils, spent oils, residues and by-products of their processing are a rich source of phenolic compounds such as phenolic acids and phenolic alcohols, secoiridoid derivatives (aglycone and ligstroside), lignans (pino and acetoxypinoresinol), flavones (luteolin and apigein), tocopherols and tocotrienols. Dietary fibre serves as a source of lignin, pectic substances, gums, resistant starch, inulin, as well as non-carbohydrate components, e.g., polyphenols, waxes, saponins, cutin, phytates, resistant proteins. Valorisation of wastes originated from animal processing by DESs means obtaining high-value chemicals including amino acids, proteins, bioactive peptides, collagen peptides, albumin etc. Through the valorisation of the mentioned waste types value-added products with potential applications in the pharmaceutical, food and cosmetic industries are produced. The paper gathered data on the used DESs, treated substances and obtained products, together with treatment conditions and the products yields. The evaluation of the state-of-the-art in the field of biowaste valorisation using DESs and NADESs led to conclusions and indication of future prospects and predicted development in this field.
  • Antibacterial and antifungal activity of phytosterols and methyl
           dehydroabietate of Norway spruce bark extracts
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Zuzana Burčová, František Kreps, Mária Greifová, Michal Jablonský, Aleš Ház, Štefan Schmidt, Igor Šurina The current study focuses on the analysis of in vitro biological activity of extract from bark of Norway spruce (Picea Abies), which can find potential application in food and cosmetic industry and pharmacology. Milled bark was subjected to Soxhlet extraction and supercritical fluid extraction to obtain two ethanol extracts. These extracts were further used to obtain their pre-extracts to n-hexane. It was investigated whether beta-sitosterol exhibits bacteriostatic activity necessary to observe antimicrobial and antifungal activity of methyl dehydroabiatate. This synergic effect and bacteriostatic activity of beta-sitosterol have not been previously reported. The greatest inhibition zone of n-hexane pre-extracts was confirmed in bacterium Pseudomonas aeruginosa (0,9 – 1,5 cm) and yeast Alternaria alternata (0,7 – 1,6 cm). It is novel, the antioxidant, antimicrobial and antifungal activity of spruce bark extracts assessed in terms of food and cosmetic fortification.
  • Genetic and phenotypic features defining industrial relevant Lactococcus
           lactis, L. cremoris and L. lactis biovar. diacetylactis strains
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Mariano Torres Manno, Federico Zuljan, Sergio Alarcón, Luis Esteban, Victor Blancato, Martín Espariz, Christian Magni Lactococcus lactis strains constitute one of the most important starter cultures for cheese production. In this study, a genome-wide analysis was performed including 68 available genomes of L. lactis group strains showing the existence of two species (L. lactis and L. cremoris) and two biovars (L. lactis biovar. diacetylactis and L. cremoris biovar. lactis). The proposed classification scheme revealed coherency among phenotypic (through in silico and in vivo bacterial function profiling), phylogenomic (through maximum likelihood trees) and genomic (using overall genome sequence-based parameters) approaches. Strain biodiversity for the industrial biovar. diacetylactis was also analyzed, finding they are formed by at least three variants with the CC1 clonal complex as the only one distributed worldwide. These findings and methodologies will help improve the selection of L. lactis group strains for industrial use as well as facilitate the interpretation of previous or future research studies on this diverse group of bacteria.
  • Crosslinked enzyme aggregates (CLEA) of phytase with soymilk proteins
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Harini Tirunagari, Shalini Basetty, Haridas B. Rode, Nitin W. Fadnavis Crosslinked Enzyme Aggregates (CLEA) of phytase (E.C. have been successfully prepared using soymilk as protein feeder. Compared to total initial activity of 4428 units used for immobilization, the recovered activity in the CLEA is enhanced to 8000 units. The CLEA retained 100% phytase activity up to 50 °C and 70% activity at 70 °C after 6 h incubation while soluble enzyme lost 50% activity at 50 °C and 80% at 70 °C. Soluble phytase has an optimum pH of 2.1 while immobilized enzyme maintains high level of activity in a broad pH range of 1–6. CLEA also retain 80% activity upon proteolytic hydrolysis with pepsin, pancreatin, trypsin and chymotrypsin, while soluble enzyme loses 40% activity under same conditions. Phytase CLEA were recycled for 5 times without loss in activity using a stirred basket reactor.
  • Identification of Pseudomonas mosselii BS011 gene clusters required for
           suppression of Rice Blast Fungus Magnaporthe oryzae
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Lijuan Wu, Wei Xiao, Guoqing Chen, Dawei Song, Maqsood Ahmed Khaskheli, Pei Li, Shiying Zhang, Guozhong Feng Pseudomonas is a Gram-negative, rod-shaped bacteria. Many members of this genus displayed remarkable physiological and metabolic activity against different plant pathogens. However, Pseudomonas mosselii has not yet been characterized in biocontrol against plant disease. Here we isolated a strain of P. mosselii BS011 from the rhizosphere soil of rice plants, and the isolate showed strong inhibitory activity against the rice blast fungus Magnaporthe oryzae. Further we sequenced the complete genome of BS011, which consist of 5.75 Mb with a circular chromosome, 5,170 protein-coding genes, 23 rRNA and 78 tRNA operons. Bioinformatic analysis revealed that seven gene clusters may be involved in the biosynthesis of metabolites. Gene deletion experiments demonstrated that the gene cluster c-xtl is required for inhibitory activity against M. oryzae. Bioassay showed that the crude extract from BS011 fermentation sample significantly inhibited the development of M. oryzae at a concentration of 10 μg/ml. Besides, we illustrated that the crude extract of BS011 impaired the appressorial formation in a dose dependent manner. Collectively our results revealed that P. mosselii BS011 is a promising biocontrol agent and the gene cluster c-xtl is essential for inhibiting the development of M. oryzae.
  • Improving cellulosic ethanol fermentability of Zymomonas mobilis by
           overexpression of sodium ion tolerance gene ZMO0119
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Xiaochuang Gao, Qiuqiang Gao, Jie Bao Inhibition of sodium ion (Na+) on Zymomonas mobilis represents an important obstacle for efficient cellulosic ethanol production. This study screened and overexpressed the genes responsible for transporting metal ions in Z. mobilis for increasing its Na+ tolerance. The ZMO0119 gene encoding Na+/H+ antiporter was identified to be highly effective for reducing intracellular Na+ concentration of Z. mobilis by improving the Na+ transport capacity. Overexpression of ZMO0119 gene in Z. mobilis significantly accelerated the cell growth, glucose consumption, and cellulosic ethanol production from the dry acid pretreated and biodetoxified corn stover feedstock. This study provided an important gene responsible for increasing the cellulosic ethanol fermentability by Z. mobilis.Graphical abstractGraphical abstract for this article
  • Characterization of the stability of Vibrio fluvialis JS17 amine
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Shan Chen, Jonatan C. Campillo-Brocal, Per Berglund, Maria Svedendahl Humble The amine transaminase from Vibrio fluvialis (Vf-ATA) is an attractive enzyme with applications within Biocatalysis for the preparation of chiral amines. Various catalytic properties of Vf-ATA have been investigated, but a biophysical characterization of its stability has been lacking. Today, the industrial application of Vf-ATA is limited by its low operational stability. In order to enhance the knowledge regarding the structural stability of ATAs, general characterizations of different ATAs are required. In this work, the stability of Vf-ATA was explored. First, the affinity between enzyme and pyridoxal-5'-phosphate (PLP) (KD value of 7.9 μM) was determined. Addition of PLP to enzyme preparations significantly improved the enzyme thermal stability by preventing enzyme unfolding. With the aim to understand if this was due to the PLP phosphate group coordination into the phosphate group binding cup, the effect of phosphate buffer on the enzyme stability was compared to HEPES buffer. Low concentrations of phosphate buffer showed a positive effect on the enzyme initial activity, while higher phosphate buffer concentrations prevented cofactor dissociation. Additionally, the effects of various amine or ketone substrates on the enzyme stability were explored. All tested amines caused a concentration dependent enzyme inactivation, while the corresponding ketones showed no or stabilizing effects. The enzyme inactivation due to the presence of amine can be connected to the formation of PMP, which forms in the presence of amines in the absence of ketone. Since PMP is not covalently bound to the enzyme, it could readily leave the enzyme upon formation. Exploring the different stability effects of cofactor, substrates, additives and buffer system on ATAs seems to be important in order to understand and improve the general performance of ATAs.
  • Opportunities in biotechnology
    • Abstract: Publication date: 20 September 2018Source: Journal of Biotechnology, Volume 282Author(s): Kevan M.A. Gartland, Jill S. Gartland Strategies for biotechnology must take account of opportunities for research, innovation and business growth. At a regional level, public-private collaborations provide potential for such growth and the creation of centres of excellence. By considering recent progress in areas such as genomics, healthcare diagnostics, synthetic biology, gene editing and bio-digital technologies, opportunities for smart, strategic and specialised investment are discussed. These opportunities often involve convergent or disruptive technologies, combining for example elements of pharma-science, molecular biology, bioinformatics and novel device development to enhance biotechnology and the life sciences. Analytical applications use novel devices in mobile health, predictive diagnostics and stratified medicine. Synthetic biology provides opportunities for new product development and increased efficiency for existing processes. Successful centres of excellence should promote public-private business partnerships, clustering and global collaborations based on excellence, smart strategies and innovation if they are to remain sustainable in the longer term.
  • The contributions of individual galactosyltransferases to protein specific
           N-glycan processing in Chinese Hamster Ovary cells
    • Abstract: Publication date: Available online 11 July 2018Source: Journal of BiotechnologyAuthor(s): Nina Bydlinski, Daniel Maresch, Valerie Schmieder, Gerald Klanert, Richard Strasser, Nicole Borth Galactosylation as part of N-glycan processing is conducted by a set of beta-1,4-galactosyltransferases (B4 GALTs), with B4 GALT1 as the dominant isoenzyme for this reaction. Nevertheless, the exact contributions of this key-player as well as of the other isoenzymes involved in N-glycosylation, B4 GALT2, B4 GALT3 and B4 GALT4, have not been studied in-depth.To increase the understanding of the protein- and site-specific activities of individual galactosyltransferases in Chinese Hamster Ovary cells, a panel of triple deletion cell lines was generated that expressed only one isoform of B4 GALT each. Two model proteins were selected for this study to cover a large spectrum of possible N-glycan structures: erythropoietin and deamine-oxidase. They were expressed as Fc-fusion constructs (EPO-Fc and Fc-DAO) and their N-glycan processing status was analyzed by site-specific mass spectrometry. The sole activity of B4 GALT1 resulted in a decrease of 15 - 21 % of fully galactosylated structures for erythropoietin, emphasizing the involvement of other isoenzymes. Interestingly, the contributions of B4 GALT2 and B4 GALT3 differed for the two model proteins. Unexpectedly, removal of galactosyltransferases influenced the overall process of N-glycan maturation, with the result of a higher occurrence of poorly processed oligosaccharides.In the context of high productivity cell lines, which can push N-glycan maturation towards incomplete galactosylation, galactosyltransferases are potential targets to ensure stable product quality. In view of our results, specifically engineered “designer” cell lines may be required for different proteins.
  • Enhancement of the antibacterial activity of an E. faecalis strain by the
           heterologous expression of enterocin A
    • Abstract: Publication date: Available online 10 July 2018Source: Journal of BiotechnologyAuthor(s): Carlos Eduardo Serrano-Maldonado, Maricarmen Quirasco The genus Enterococcus occurs as native microbiota of fermented products due to its broad environmental distribution and its resistance to salt concentrations. Enterococcus faecalis F, a non-pathogenic strain isolated from a ripened cheese, has demonstrated useful enzymatic capabilities, a probiotic behavior and antibacterial activity against some food-borne pathogens, mainly due to peptidoglycan hydrolase activity. Its use as a natural pathogen-control agent could be further enhanced through the production of a bacteriocin, e.g. Enterocin A, because of its remarkable antilisterial activity. In this work, a markerless allelic insertion method was used to obtain an enterococcal strain capable of producing a functional enterocin. Agar diffusion tests showed that the recombinant strain was active against Staphylococcus aureus, Listeria monocytogenes and the pathogenic strain E. faecalis V583. When grown in liquid culture together with L. monocytogenes, it attained a two-log reduction of the pathogen counts in lesser time relative to the native strain. Because the DNA construction is integrated into the chromosome, the improved strain avoids the use of antibiotics as selective pressure; besides, it does not require an inductor because of the inclusion of a constitutive promoter in the construction. Its technological and antibacterial capabilities make the improved E. faecalis strain a potential culture for use in the food industry.
  • Extraction of astaxanthin from microalga Haematococcus pluvialis in red
           phase by using Generally Recognized As Safe solvents and accelerated
    • Abstract: Publication date: Available online 9 July 2018Source: Journal of BiotechnologyAuthor(s): Antonio Molino, Juri Rimauro, Patrizia Casella, Antonietta Cerbone, Vincenzo Larocca, Simeone Chianese, Despina Karatza, Sanjeet Mehariya, Angelo Ferraro, Evangelos Hristoforou, Dino Musmarra Solvent Extraction was tested to extract astaxanthin from Haematococcus pluvialis in red phase (HPR), by investigating effects of solvents, extraction pressure and temperature. Astaxanthin isomers were identified and quantified in the extract. The performances of acetone and ethanol, Generally Recognized As Safe (GRAS) solvents, were explored. Negligible effect of pressure was found, while with increasing extraction temperature astaxanthin recovery increased till a maximum value, beyond which thermal degradation seemed to be greater than the positive effect of temperature on extraction. Furthermore, to maximize the extraction yield of astaxanthin, mechanical pre-treatment of HPR biomass was carried out and several extraction runs were consecutively performed. Experimental results showed that after the mechanical pre-treatment the astaxanthin recovery strongly increased while a single extraction run of 20 minutes was sufficient to extract more than 99% of total astaxanthin extracted. After pre-treatment, maximum recovery of about 87% was found for acetone (pressure = 100 bar; temperature = 40 °C; total time = 60 minutes).
  • Over-expression of SINAL7 increases biomass and drought tolerance, and
           also delays senescence in Arabidopsis
    • Abstract: Publication date: Available online 9 July 2018Source: Journal of BiotechnologyAuthor(s): Diego A. Peralta, Alejandro Araya, Diego F. Gomez-Casati, María V. Busi The seven in absentia like 7 gene (At5g37890, SINAL7) from Arabidopsis thaliana encodes a RING finger protein belonging to the SINA superfamily that possesses E3 ubiquitin-ligase activity. SINAL7 has the ability to self-ubiquitinate and to mono-ubiquitinate glyceraldehyde-3-P dehydrogenase 1 (GAPC1), suggesting a role for both proteins in a hypothetical signaling pathway in Arabidopsis. In this study, the in vivo effects of SINAL7 on plant physiology were examined by over-expressing SINAL7 in transgenic Arabidopsis plants. Phenotypic and gene expression analyses suggest the involvement of SINAL7 in the regulation of several vegetative parameters, essentially those that affect the aerial parts of the plants. Over-expression of SINAL7 resulted in an increase in the concentrations of hexoses and sucrose, with a concommitant increase in plant biomass, particularly in the number of rosette leaves and stem thickness. Interestingly, using the CAB1 (chlorophyll ab binding protein 1) gene as a marker revealed a delay in the onset of senescence. Transgenic plants also displayed a remarkable level of drought resistance, indicating the complexity of the response to SINAL7 over-expression.
  • The diploid genome of the only sclerotia-forming wild-type species in the
           genus Pleurotus -Pleurotus tuber-regium - provides insights into the
           mechanism of its biomass conversion from lignocellulose substrates
    • Abstract: Publication date: Available online 9 July 2018Source: Journal of BiotechnologyAuthor(s): Ka-Lung Lam, Kaiwei Si, Xiyang Wu, Shuze Tang, Xiaohui Sun, Hoi-Shan Kwan, Chi-Keung Peter Cheung Pleurotus tuber-regium (Fr.) Singer, being a white-rot fungus, is widely used for food and medicine in the Asia-Pacific region. In this study, we sequenced and annotated the genome of a dikaryon P. tuber-regium wild strain to provide a better understanding of the carbohydrate-active enzymes (CAZymes) involved in the bio-conversion of lignocellulose to beta-glucan reserves in this sclerotia-forming Pleurotus mushroom with reference to enzyme participated in cellulosic compound breakdown and glucan reserve biosynthesis. The present genomic data provides new insights for lignocellulose bioconversion of white-rot fungus for the genus Pleurotus.
  • Influence of hydraulic retention time and carbon loading rate on the
           production of algae
    • Abstract: Publication date: Available online 7 July 2018Source: Journal of BiotechnologyAuthor(s): C.M. Fernandez-Marchante, Y. Asensio, J. Lobato, J. Villaseñor, P. Cañizares, M.A. Rodrigo This paper is focused on the assessment of the production of algae in batch bioreactors. Hydraulic retention time, carbon loading rate and light color were the inputs of the study and algae production the main output. Bioreactors were operated in semi-continuous mode and tests lasted two months, more than two times the period required to meet a steady-state response. This steady-state was verified with plateau responses in both, soluble parameters and suspended solids. Results points out the great relevance of temperature. Likewise, they show that green light improves the production of algae, as well as long HRT and high CLR. Maximum production rates attained were in the range 4-14 mg d-1 L-1. The ratio COD /TSS for this biofuel was almost constant (3.13 mg COD mg-1 TSS) but the quality of the product obtained in terms of the Mean Oxidation State of Carbon is completely different. Longer HRT leads to lower MOSC and hence to potentially more valuable fuels.
  • Deciphering Molecular Consequences of the Proprotein Convertase 1/3
           Inhibition in Macrophages for Application in Anti-tumour Immunotherapy
    • Abstract: Publication date: Available online 7 July 2018Source: Journal of BiotechnologyAuthor(s): Franck Rodet, Alice Capuz, Tsukasa Hara, Rinaldo van Meel, Marie Duhamel, Mélanie Rose, Antonella Raffo Romero, Isabelle Fournier, Michel Salzet During tumour development, macrophages are recruited to the tumour site and orientated towards an anti-inflammatory phenotype. Due to their immunosuppressive function, tumour associated macrophages (TAMs) are recognized as major components in tumour progression. Changing these macrophages to a pro-inflammatory phenotype is thus extensively studied as a potential means for developing novel anti-tumour therapy. In this context, we found that the Proprotein convertase 1/3 (PC1/3) is a relevant target. Proteomic analysis reveals that PC1/3 knockdown (KD) macrophages present all the characteristic of activated pro-inflammatory macrophages. Moreover, in PC1/3 KD macrophages, TLR4 and TLR9 signaling pathways can be enhanced leading to the secretion of pro-inflammatory factors and anti-tumour factors. To develop an efficient anti-tumour immunotherapy, we may (i) target TAMs directly inside the tumour site for PC1/3 inhibition and TLR activation and used them as “Trojan macrophages” or (ii) directly take advantage of PC1/3 inhibited macrophages and use them as “drone macrophages” by activating them “at distance” with a TLR ligand. Therefore, PC1/3 inhibited macrophages constitute an innovative cell therapy to treat tumours efficiently.
  • A Multifunctional Tag with the Ability to Benefit the Expression,
           Purification, Thermostability and Activity of Recombinant Proteins
    • Abstract: Publication date: Available online 4 July 2018Source: Journal of BiotechnologyAuthor(s): Weixin Zhao, Liming Liu, Guocheng Du, Song LiuABSTRACTIn this study, a novel multifunctional tag, S1v1 (AEAEAHAH)2, was generated from a self-assembling amphipathic peptide in the Zuotin protein sequence by replacing lysine residues with histidine residues. After fusing S1v1 at the N-terminus through a PT-linker, the expressions of polygalacturonate lyase (PGL), lipoxygenase (LOX) and green fluorescent protein (GFP) were enhanced by 3.8, 0.2 and 1.52-fold, respectively,compared to the wild-type proteins. However, the frequently used His-tag with a PT-linker had negligible effects on expression. Moreover, the three S1v1 fusions were purified with high purities and acceptable recovery rates due to their affinity to the nickel column. In contrast, PGL and LOX fused with His-tag were unable to be adsorbed by the nickel column, and His-tag fusion only achieved 8.23% of GFP recovery in the same purification process.In addition, S1v1 fusions induced the enhancement of thermostabilties and/or activities of PGL, LOX and GFP. These results indicated that S1v1 was much more effective than the frequently used His-tag during protein expression and purification in these cases, and will be especially suitable for those proteins requiring the simultaneous enhancement of expression, production and catalytic properties.
  • Evaluating the potential of indigenous methanogenic consortium for
           enhanced oil and gas recovery from high temperature depleted oil reservoir
    • Abstract: Publication date: Available online 1 July 2018Source: Journal of BiotechnologyAuthor(s): Rohit Rathi, Meeta Lavania, Vipin Kukreti, Banwari Lal In past years, lots of research has been focussed on the indigenous bacteria and their mechanisms, which help in enhanced oil recovery. Most of the oil wells in Indian subcontinent have temperature higher than 60 °C. Also, the role of methanogenic consortia from high temperature petroleum reservoir for enhanced oil recovery (EOR) has not been explored much. Hence, in the present study methanogens isolated from thermophilic oil wells (70 °C) were evaluated for enhanced oil recovery. Methane gas is produced by methanogens, which helps in oil recovery from depleted oil wellsthrough reservoir re-pressurization and also can be recovered from reservoir along with crude oil as alternative energy source. Therefore, in this study indigenous methanogenic consortium (TERIL146) was enriched from high temperature oil reservoir showing (12 mmol/l) gas production along with other metabolites. Sequencing analysis revealed the presence of Methanothermobacter sp., Thermoanaerobacter sp., Gelria sp. and Thermotoga sp. in the consortium. Furthermore the developed indigenous consortium TERIL146 showed 8.3 % incremental oil recovery in sandpack assay. The present studydemonstrates successful recovery of both oil and energy (gas) by the developed indigenous methanogenic consortium TERIL146 for potential application in thermophilicdepleted oil wells of Indian subcontinent.
  • Editorial
    • Abstract: Publication date: Available online 6 June 2018Source: Journal of BiotechnologyAuthor(s):
  • l-LcLDH1,+an+l-lactate+dehydrogenase+from+Lactobacillus+casei,+to+improve+its+specific+activity+and+catalytic+efficiency+towards+phenylpyruvic+acid&rft.title=Journal+of+Biotechnology&rft.issn=0168-1656&">Directed modification of l-LcLDH1, an l-lactate dehydrogenase from
           Lactobacillus casei, to improve its specific activity and catalytic
           efficiency towards phenylpyruvic acid
    • Abstract: Publication date: Available online 22 May 2018Source: Journal of BiotechnologyAuthor(s): Jian-Fang Li, Xue-Qing Li, Yan Liu, Feng-Jiao Yuan, Ting Zhang, Min-Chen Wu, Ji-Ru Zhang To improve the specific activity and catalytic efficiency of l-LcLDH1, an NADH-dependent allosteric l-lactate dehydrogenase from L. casei, towards phenylpyruvic acid (PPA), its directed modification was conducted based on the semi-rational design. The three variant genes, Lcldh1Q88R, Lcldh1I229A and Lcldh1T235G, were constructed by whole-plasmid PCR as designed theoretically, and expressed in E. coli BL21(DE3), respectively. The purified mutant, l-LcLDH1Q88R or l-LcLDH1I229A, displayed the specific activity of 451.5 or 512.4 U/mg towards PPA, by which the asymmetric reduction of PPA afforded l-phenyllactic acid (PLA) with an enantiomeric excess (eep) more than 99%. Their catalytic efficiencies (kcat/Km) without d-fructose-1,6-diphosphate (d-FDP) were 4.8- and 5.2-fold that of l-LcLDH1. Additionally, the kcat/Km values of l-LcLDH1Q88R and l-LcLDH1I229A with d-FDP were 168.4- and 8.5-fold higher than those of the same enzymes without d-FDP, respectively. The analysis of catalytic mechanisms by molecular docking (MD) simulation indicated that substituting I229 in l-LcLDH1 with Ala enlarges the space of substrate-binding pocket, and that the replacement of Q88 with Arg makes the inlet of pocket larger than that of l-LcLDH1.
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