Journal of Bioscience and Bioengineering

Publisher: Nihon Seibutsu Kogakkai, Elsevier

Journal description

Current impact factor: 1.79

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 1.79
2012 Impact Factor 1.737
2011 Impact Factor 1.793
2010 Impact Factor 1.707
2009 Impact Factor 1.749
2008 Impact Factor 1.702
2007 Impact Factor 1.782
2006 Impact Factor 1.136
2005 Impact Factor 0.948
2004 Impact Factor 0.802
2003 Impact Factor 0.993
2002 Impact Factor 0.777
2001 Impact Factor 0.865
2000 Impact Factor 0.749

Impact factor over time

Impact factor

Additional details

5-year impact 1.99
Cited half-life 7.00
Immediacy index 0.29
Eigenfactor 0.01
Article influence 0.53
Other titles Journal of bioscience and bioengineering (En ligne)
ISSN 1347-4421
OCLC 56331911
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details


  • Pre-print
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    • Deposit due to Funding Body, Institutional and Governmental policy or mandate only allowed where separate agreement between repository and the publisher exists.
    • Permitted deposit due to Funding Body, Institutional and Governmental policy or mandate, may be required to comply with embargo periods of 12 months to 48 months .
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    • Published source must be acknowledged
    • Must link to journal home page or articles' DOI
    • Publisher's version/PDF cannot be used
    • Articles in some journals can be made Open Access on payment of additional charge
    • NIH Authors articles will be submitted to PubMed Central after 12 months
    • Publisher last contacted on 18/10/2013
  • Classification
    ​ green

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: Long-term storage in aqueous solution has been demanded for the practical application of therapeutic proteins. Recently, a precipitation-redissolution method was proposed to prepare salt-dissociable protein-polyelectrolyte complex (PPC). To elucidate the utility of the complex for storage of proteins, we investigated the stress tolerance of PPC precipitates containing l-asparaginase (ASNase) and poly-l-lysine (polyK). PPC precipitate containing ASNase and polyK was prepared by precipitation-redissolution method. The sample was treated to three types of stress, i.e., heat, shaking, and oxidation. The protein concentration, enzyme activity, and CD spectrum of the supernatants of samples were measured after stressed. PPC precipitate consisting of ASNase and polyK showed tolerance against thermal and shaking stress compared to the native solution. In addition, PPC precipitate protected ASNase from inactivation by oxidation. PPC precipitate of ASNase/polyK complex successfully stabilized ASNase against physicochemical stresses. These results suggest that the PPC precipitate has great potential as a storage method in aqueous solution for unstable proteins. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 05/2015; DOI:10.1016/j.jbiosc.2015.04.010
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    ABSTRACT: Lantibiotics are antibacterial peptides containing unique thioether cross-links termed lanthionine and methyllanthionine. NukM, the modifying enzyme of nukacin ISK-1, which is produced by Staphylococcus warneri ISK-1, catalyzes the dehydration of specific Ser/Thr residues in a precursor peptide, followed by conjugative addition of intramolecular Cys to dehydrated residues to generate a cyclic structure. By contrast, the precursor peptide of nisin is modified by 2 enzymes, NisB and NisC, which mediate dehydration and cyclization, respectively. While the C-terminal domain of NukM is homologous to NisC, the N-terminal domain has no homology with other known proteins. We expressed and characterized the N- and C-terminal domains of NukM, NukMN, and NukMC, separately. In vitro reconstitution revealed that full-length NukM fully modified the substrate peptide NukA. NukMN partially phosphorylated, dehydrated, and cyclized NukA. By contrast, NukMC did not catalyze dehydration, phosphorylation, or cyclization reactions. Interaction studies using surface plasmon resonance analysis indicated that NukM and NukMN can bind NukA with high affinity, whereas NukMC has low substrate-recognition activity. These results suggest that NukMN is mainly responsible for substrate recognition and dehydration and that the whole NukM structure, including the C-terminal domain, is required for the complete modification of NukA. To the best of our knowledge, this is the first report providing insights into the in vitro catalytic activity of individual domains of a LanM-type modification enzyme. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 05/2015; DOI:10.1016/j.jbiosc.2015.03.020
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    ABSTRACT: Ophiostoma piceae secretes a versatile sterol-esterase (OPE) that shows high efficiency in both hydrolysis and synthesis of triglycerides and sterol esters. This enzyme produces aggregates in aqueous solutions, but the recombinant protein, expressed in Komagataella (synonym Pichia) pastoris, showed higher catalytic efficiency because of its higher solubility. This fact owes to a modification in the N-terminal sequence of the protein expressed in Pichia pastoris, which incorporated 4-8 additional amino acids, affecting its aggregation behavior. In this study we present a newly engineered P. pastoris strain with improved protein production. We also produced the recombinant protein in the yeast Saccharomyces cerevisiae and in the prokaryotic host Escherichia coli, corroborating that the presence of these N-terminal extra amino acids affected the protein's solubility. The OPE produced in the new P. pastoris strain presented the same physicochemical properties than the old one. An inactive form of the enzyme was produced by the bacterium, but the recombinant esterase from both yeasts was active even after its enzymatic deglycosylation, suggesting that the presence of N-linked carbohydrates in the mature protein is not essential for enzyme activity. Although the yield in S. cerevisiae was lower than that obtained in P. pastoris, this work demonstrates the importance of the choice of the heterologous host for successful production of soluble and active recombinant protein. In addition, S. cerevisiae constitutes a good engineering platform for improving the properties of this biocatalyst. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 05/2015; DOI:10.1016/j.jbiosc.2015.04.005
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    ABSTRACT: Three antigens (NcSAG1, NcSRS2 and NcMIC3) from Neospora caninum were expressed using the BmNPV bacmid system in silkworm larvae and purified from the hemolymph. From 20 silkworm larvae, 1.5, 1.2 and 1.4 mg of purified recombinant NcSAG1, NcSRS2 and NcMIC3 were obtained, respectively. When each purified recombinant antigen was immunized with Freund's incomplete adjuvant (FIA) to mice, recombinant NcSAG1 induced a Th2 immune response in immunized mice and produced a SAG1-specific antibody. In the experiment where NcSAG1-immunized mice were challenged with N. caninum, the cerebral N. caninum burden was significantly reduced compared with that of either the FIA- or PBS-immunized mice. Recombinant NcSRS2 or NcMIC3 induced both Th1 and Th2 immune responses, but NcMIC3-immunization did not induce significant production of NcMIC3-specific antibodies. These results suggest that the silkworm can produce recombinant antigens of N. caninum, which can be used as a recombinant vaccine against N. caninum. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.04.002
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    ABSTRACT: Transductions of exogenous proteins into cells enable the precise study of the effect of the transduced proteins on cellular functions. Accordingly, the protein transduction technique, which can control the release of proteins into the cytosol with certainty and high-throughput, is highly desired in various research fields. In this study, streptavidin (SA) labeled with a photosensitizer and cell-permeable peptides (CPP) was proposed as a nano-carrier for light-controlled protein transduction. SA was modified with biotinylated oligo-arginine peptides (Rpep), which were functionalized with Alexa Fluor 546 (AF546), to achieve cell penetrating and endosomal escape functionalities. The SA-Rpep complex was efficiently internalized into living HeLa cells corresponding to the length and the modification number of Rpep. SA conjugated with more than three equimolar AF546-modified Rpep consisting of fifteen arginine residues was achieved to diffuse throughout the cytosol without cytotoxicity by irradiation of the excitation light for AF546. The optimized nano-carrier was confirmed to transduce a biotinylated model cargo protein, enhanced green fluorescent protein fused with thioredoxin (tEGFP) into the cytosol at the light-irradiated area. The results provided proof-of-principle that SA possessing multiple AF546-modified Rpep has the potential to be a versatile and facile carrier for light-controlled protein transduction into the cytosol of mammalian cells. Copyright © 2015. Published by Elsevier B.V.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.04.001
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    ABSTRACT: By a global search of the genome database of Aspergillus oryzae, we found 23 genes encoding putative β-glucosidases, among which 10 genes with a signal peptide belonging to glycoside hydrolase family 3 (GH3) were overexpressed in A. oryzae using the improved glaA gene promoter. Consequently, crude enzyme preparations from three strains, each harboring the genes AO090038000223 (bglA), AO090103000127 (bglF), and AO090003001511 (bglJ), showed a substrate preference toward p-nitrophenyl-β-d-glucopyranoside (pNPGlc) and thus were purified to homogeneity and enzymatically characterized. All the purified enzymes (BglA, BglF, and BglJ) preferentially hydrolyzed aryl β-glycosides, including pNPGlc, rather than cellobiose, and these enzymes were proven to be aryl β-glucosidases. Although the specific activity of BglF toward all the substrates tested was significantly low, BglA and BglJ showed appreciably high activities toward pNPGlc and arbutin. The kinetic parameters of BglA and BglJ for pNPGlc suggested that both the enzymes had relatively higher hydrolytic activity toward pNPGlc among the fungal β-glucosidases reported. The thermal and pH stabilities of BglA were higher than those of BglJ, and BglA was particularly stable in a wide pH range (pH 4.5-10). In contrast, BglJ was the most heat- and alkaline-labile among the three β-glucosidases. Furthermore, BglA was more tolerant to ethanol than BglJ; as a result, it showed much higher hydrolytic activity toward isoflavone glycosides in the presence of ethanol than BglJ. This study suggested that the mining of novel β-glucosidases exhibiting higher activity from microbial genome sequences is of great use for the production of beneficial compounds such as isoflavone aglycones. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.019
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    ABSTRACT: Studying metabolic directions and flow rates in cultured mammalian cells can provide key information for understanding metabolic function in the fields of cancer research, drug discovery, stem cell biology, and antibody production. In this work, metabolic engineering methodologies including medium component analysis, (13)C-labeling experiments, and computer-aided simulation analysis were applied to characterize the metabolic phenotype of soft tissue sarcoma cells derived from p53-null mice. Cells were cultured in medium containing [1-(13)C] glutamine to assess the level of reductive glutamine metabolism via the reverse reaction of isocitrate dehydrogenase (IDH). The specific uptake and production rates of glucose, organic acids, and the 20 amino acids were determined by time-course analysis of cultured media. Gas chromatography-mass spectrometry analysis of the (13)C-labeling of citrate, succinate, fumarate, malate, and aspartate confirmed an isotopically steady state of the cultured cells. After removing the effect of naturally occurring isotopes, the direction of the IDH reaction was determined by computer-aided analysis. The results validated that metabolic engineering methodologies are applicable to soft tissue sarcoma cells derived from p53-null mice, and also demonstrated that reductive glutamine metabolism is active in p53-null soft tissue sarcoma cells under normoxia. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.04.003
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    ABSTRACT: Despite the growing numbers of successful applications in regenerative medicine, biotechnologies for evaluating the quality of cells remain limited. To evaluate the cultured cells non-invasively, image-based cellular assessment method holds great promise. However, although there are various image-processing algorithms, very few studies have focused to prove the effectiveness of phase contrast images with risk assessment example that reflects actual difficulties in regenerative medicine products. In this study, we developed a simple image-processing method to recognize the number of dividing cells in time-course phase-contrast microscopic images, and applied this method to assess the irregular proliferation behavior in normal cells. Practically, as a model, rapid proliferating human fibrosarcoma cells were mixed in normal human fibroblasts in the same culture dish, and their sarcoma existence was evaluated. As a result, the existence of sarcoma population in normal cell sample could be feasibly detected within earliest period of cell culture by their irregular rise of accumulated counts of dividing cells. Our image-processing technique also illustrates the technical effectiveness of combining intra-frame and inter-frame image processing to accurately count only the dividing cells. Our concept of focused counting of dividing cells shows a successful example of image-based analysis to quickly and non-invasively monitor the regular state of regenerative medicine products. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.002
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    ABSTRACT: Glucose dehydrogenase (GDH) is of interest for its potential applications in the field of glucose sensors. To improve the performance of glucose sensors, GDH is required to have strict substrate specificity. A novel flavin adenine dinucleotide (FAD)-dependent GDH was isolated from Mucor prainii NISL0103 and its enzymatic properties were characterized. This FAD-dependent GDH (MpGDH) exhibited high specificity toward glucose. High specificity for glucose was also observed even in the presence of saccharides such as maltose, galactose and xylose. The molecular masses of the glycoforms of GDH ranged from 90 to 130 kDa. After deglycosylation, a single 80 kDa band was observed. The gene encoding MpGDH was cloned and expressed in Aspergillus sojae. The apparent kcat and Km values of recombinant enzyme for glucose were found to be 749.7 s(-1) and 28.3 mM, respectively. The results indicated that the characteristics of MpGDH were suitable for assaying blood glucose levels. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.012
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    ABSTRACT: Currently, antibodies play major role in treating a wide variety of human diseases (e.g., cancer, viral infection, inflammation). Those pharmaceutic antibodies have become major therapeutic reagents in the pharmaceutical drug market. In addition to full-length antibodies, the market of antibody fragments, which offer potential advantages in clinical use as well as diagnostics, is gradually growing. As the demand for antibody therapeutics increase, the development of host systems for enhanced, and less expensive, production has also become more important. All therapeutic antibodies approved to date are predominantly produced in mammalian hosts, but due to drawbacks such as high production cost and long-term cultivation, the alternative use of bacteria and yeasts has been seriously considered. Recently, there have been reports of substantial progress in genetic engineering and systems biotechnology, results in development of potential hosts that overcame the critical limitations in bacterial and yeast cells, and much enhanced productivity of functional antibodies. In this review, we highlight recent, significant progress made in the engineering of bacterial and yeast cells for enhanced production of functional antibodies. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.009
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    ABSTRACT: The secretion efficiency of foreign proteins in recombinant microbes is strongly dependent on the combination of the signal peptides (SPs) used and the target proteins; therefore, identifying the optimal SP sequence for each target protein is a crucial step in maximizing the efficiency of protein secretion in both prokaryotes and eukaryotes. In this study, we developed a novel method, named the SP optimization tool (SPOT), for the generation and rapid screening of a library of SP-target gene fusion constructs to identify the optimal SP for maximizing target protein secretion. In contrast to libraries generated in previous studies, SPOT fusion constructs are generated without adding the intervening sequences associated with restriction enzyme digestion sites. Therefore, no extra amino acids are inserted at the N-terminus of the target protein that might affect its function or conformational stability. As a model system, β-galactosidase (LacA) from Aspergillus oryzae was used as a target protein for secretion from Saccharomyces cerevisiae. In total, 60 SPs were selected from S. cerevisiae secretory proteins and utilized to generate the SP library. While many of the SP-LacA fusions were not secreted, several of the SPs, AGA2, CRH1, PLB1, and MF(alpha)1, were found to enhance LacA secretion compared to the WT sequence. Our results indicate that SPOT is a valuable method for optimizing the bioproduction of any target protein, and could be adapted to many host strains. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.003
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    ABSTRACT: S-Adenosyl-l-methionine (SAM) is a major biological methyl group donor, and is used as a nutritional supplement and prescription drug. Yeast is used for the industrial production of SAM owing to its high intracellular SAM concentrations. To determine the regulation mechanisms responsible for such high SAM production, (13)C-metabolic flux analysis ((13)C-MFA) was conducted to compare the flux distributions in the central metabolism between Kyokai no. 6 (high SAM-producing) and S288C (control) strains. (13)C-MFA showed that the levels of tricarboxylic acid (TCA) cycle flux in SAM-overproducing strain were considerably increased compared to those in the S228C strain. Analysis of ATP balance also showed that a larger amount of excess ATP was produced in the Kyokai 6 strain because of increased oxidative phosphorylation. These results suggest that high SAM production in Kyokai 6 strains could be attributed to enhanced ATP regeneration with high TCA cycle fluxes and respiration activity. Thus, maintaining high respiration efficiency during cultivation is important for improving SAM production. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.010
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    ABSTRACT: Counterselection is a genetic engineering technique to eliminate specific genetic fragments containing selectable marker genes. Although the technique is widely used in bacterial genome engineering and plasmid curing experiments, the repertoire of the markers usable in Escherichia coli is limited. Here we developed a novel counterselection method in E. coli based on antisense RNA (asRNA) technology directed against toxin-antitoxin (TA) modules. Under normal conditions, excess antitoxin neutralizes its cognate toxin and thus the module is stably maintained in the genome. We hypothesised that repression of an antitoxin gene would perturb cell growth due to the toxin being released. We designed asRNAs corresponding to all 19 type II antitoxins encoded in the E. coli genome. asRNAs were then conditionally expressed; repression of MqsA in the MqsR/MqsA module had the greatest inhibitory effect, followed by RnlB in the RnlA/RnlB module. The utility of asRNA(MqsA) as a counterselection marker was demonstrated by efficient plasmid curing and strain improvement experiments. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.008
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    ABSTRACT: Design of porous scaffolds in tissue engineering field was challenging. Uniform immobilization of cells in the scaffolds with high porosity was essential for homogeneous tissue formation. The present study was aimed at fabricating uniformly cell-laden porous scaffolds with porosity >74% using the gas-in-liquid foam templating technique. To this end, we used gelatin, microbial transglutaminase and argon gas as a scaffold material, cross-linker of the protein and porogen of scaffold, respectively. We confirmed that a porosity of >74% could be achieved by increasing the gas volume delivered to a gelatin solution. Pore size in the scaffold could be controlled by stirring speed, stirring time and the pore size of the filter through which the gas passed. The foaming technique enabled us to uniformly immobilize a human hepatoblastoma cell line in scaffold. Engraftment efficiency of the cell line entrapped within the scaffold in nude mice was higher than that of cells in free-form. These results showed that the uniformly cell-laden porous scaffolds were promising for tissue engineering. Copyright © 2015. Published by Elsevier B.V.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.017
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    ABSTRACT: Anammox is an environmental-friendly and cost-effective technology for nitrogen removal. This study provides the nitrogen removal profiles, physiological traits of anammox bacteria culture under the substrate deficiency conditions at the optimal cultivation temperature 35°C. The determined period of starvation tolerance was 4 weeks in the absence of nitrite, 5 weeks in the absence of ammonium, as well as 7 weeks for the absence of these two substrates at 36°C, pH 7-8 and anaerobic conditions. The physiological traits of bacteria consortium were identified through flow cytometry (FCM) analysis, and the ordinal change of increased RNA synthesizing amounts, phosphatidylserine exposure and bacteria death occurred under starvation stress. In addition, the starvation induced the increased protein content in extracellular polymeric substances and the poorer bacteria settling capacity. This study helps to develop a better understanding of anammox process in engineering environment. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.02.016
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    ABSTRACT: The purpose of this study was to elucidate the molecular mechanisms of microRNA-203 (miR-203) as a tumor suppressor in KB human oral cancer cells. MicroRNA microarray results showed that the expression of miR-203 was significantly down-regulated in KB cells compared with normal human oral keratinocytes. The viability of KB cells was decreased by miR-203 in the time- and dose-dependent manners. In addition, over-expressed miR-203 not only increased the nuclear condensation but also significantly increased the apoptotic population of KB cells. These results indicated that the over-expression of miR-203 induced apoptosis of KB cells. Furthermore, the target gene array analyses revealed that the expression of Yes-1, a member of the Src family kinases (SFKs), was significantly down-regulated by miR-203 in KB cells. Moreover, both the mRNA and protein levels of Yes-1 were strongly reduced in KB cells transfected with miR-203. Therefore, these results indicated that Yes-1 is predicted to be a potential target gene of miR-203. Through a luciferase activity assay, miR-203 was confirmed to directly targets the Yes-1 3' untranslated region (UTR) to suppress gene expression. Therefore, our findings indicate that miR-203 induces the apoptosis of KB cells by directly targeting Yes-1, suggesting its application in anti-cancer therapeutics. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.02.002
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    ABSTRACT: A strain of Acinetobacter sp. Y1, which exhibited an amazing ability to remove ammonium, nitrite and nitrate, was isolated from the activated sludge of a coking wastewater treatment plant. The aim of this work was to study the ability, influence factors and possible pathway of nitrogen removal by Acinetobacter sp. Y1. Results showed that maximum removal rate of NH4(+)-N by the strain was 10.28 mg-N/L/h. Carbon source had significant influence on the growth and ammonium removal efficiencies of strain Y1. Pyruvate, citrate and acetate were favourable carbon sources for the strain. Temperature, pH value and shaking speed could affect the growth and nitrogen removal ability. Nitrate or nitrite could be used as a sole nitrogen source for the growth and removed efficiently by the strain. N2 levels increased to 53.74%, 50.21% and 55.13% within 36 h when 100 mg/L NH4(+)-N, NO2(-)-N or NO3(-) -N was used as sole nitrogen source in the gas detection experiment. The activities of hydroxylamine oxidoreductase (HAO), nitrate reductase (NR) and nitrite reductase (NiR), which are key enzymes in heterotrophic nitrification and aerobic denitrification, were all detectable in the strain. Consequently, a possible pathway for ammonium removal by the strain was also suggested. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.015
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    ABSTRACT: This study described the genetic map of tandem genes (est1 and est119) encoding cutinase-type polyesterases in Thermobifida alba AHK119 and comparison of wild type and mutant enzymes of Est1 and Est119. Two genes were independently and constitutively expressed. The activity of Est1 was higher by approximately 1.6-1.7-fold than that of Est119 towards p-nitrophenyl butyrate, although both enzymes shared 95% sequence identity and 98% similarity and possessed similar 3D structures except that several amino acids in the probable substrate-docking loops were different from each other. Calcium ion enhanced the activity and the thermostability of both enzymes. Based on conserved sequences among Thermobifida cutinases, valine, proline and lysine were introduced into Est1 at Ala68, Thr253 and Met256, respectively. Among wild and mutant enzymes of Est119 and Est1, Est1 (A68V/T253P) possessed three prolines in the substrate-docking loops and displayed the highest thermostability that spotlighted the important effect of proline numbers in the loops. Est1 (A68V/T253P) was stable for 1 h below 60°C and even at 65°C, more than 70% and 50% activities were maintained after 30 and 60 min, respectively. Est1 (A68V/T253P) degraded various aliphatic and aliphatic-co-aromatic polyesters and hydrophilized an amorphous PET film. The enzyme hydrolyzed a PET trimer model compound, indicating its specificity towards an ester bond between terephthalic acid and ethylene glycol. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
    Journal of Bioscience and Bioengineering 04/2015; DOI:10.1016/j.jbiosc.2015.03.006