Enzyme and Microbial Technology最新文献

{"title":"Penicillin binding proteins-based immunoassay for the selective and quantitative determination of beta-lactam antibiotics","authors":"Rilong Liu ,&nbsp;Hangzhen Lan ,&nbsp;Song Yan ,&nbsp;Lu Huang ,&nbsp;Daodong Pan ,&nbsp;Yichun Wu","doi":"10.1016/j.enzmictec.2024.110507","DOIUrl":"10.1016/j.enzmictec.2024.110507","url":null,"abstract":"<div><p>An immunoassay method based on penicillin-binding protein (PBP) was developed for the quantitative determination of 10 kinds of beta-lactam antibiotics (BLAs). First, two kinds of PBPs, which are named PBP1a and PBP2x, were expressed and purified, and they were characterized by SDS-PAGE and western blotting analysis. Then, the binding activity of PBP1a and PBP2x to template BLAs, cefquinome (CEFQ) and ampicillin (AMP), was determined. The effect of the buffer solution system, e.g., pH, ion concentration, and organic solvent, on the immune interaction efficiency between PBPs and BLAs was also evaluated. In the end, the PBP-based immunoassay method was developed and validated for the detection of 10 kinds of BLAs. Under optimal conditions, PBPs exhibited high binding affinity to BLAs. In addition, this method showed a high sensitivity for the detection of 10 kinds of BLAs with the limits of detection from 0.21 to 9.12 ng/mL, which are much lower than their corresponding maximum residual limit of European Union (4–100 ng/mL). Moreover, the developed PBP-immunoassay was employed for BLA detection from milk samples, and satisfactory recoveries (68.9–101.3 %) were obtained.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110507"},"PeriodicalIF":3.4,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142145407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mutant β-fructofuranosidase synthesizing blastose [β-d-Fruf-(2→6)-d-Glcp]","authors":"Atsuki Takagi,&nbsp;Takayoshi Tagami,&nbsp;Masayuki Okuyama","doi":"10.1016/j.enzmictec.2024.110500","DOIUrl":"10.1016/j.enzmictec.2024.110500","url":null,"abstract":"<div><p>Fructooligosaccharides (FOS) are leading prebiotics that help keep the gut healthy and aid wellness by stimulating the growth and activity of beneficial intestinal bacteria. The best-studied FOS are inulin-type FOS, mainly oligosaccharides with β-Fru<em>f</em>-(2→1)-Fru<em>f</em> linkages, including 1-kestose [β-Fru<em>f</em>-(2→1)-β-Fru<em>f</em>-(2↔1)-α-Glc<em>p</em>] and nystose [β-Fru<em>f</em>-(2→1)-β-Fru<em>f</em>-(2→1)-β-Fru<em>f</em>-(2↔1)-α-Glc<em>p</em>]. However, the properties of other types of FOS—levan-type FOS with β-Fru<em>f</em>-(2→6)-Fru<em>f</em> linkages and neo-type FOS with β-Fru<em>f</em>-(2→6)-Glc<em>p</em> linkages—remain ambiguous because efficient methods have not been established for their synthesis. Here, using site-saturation mutation of residue His79 of β-fructofuranosidase from <em>Zymomonas mobilis</em> NBRC13756, we successfully obtained a mutant β-fructofuranosidase that specifically produces neo-type FOS. The H79G enzyme variant loses the native β-Fru<em>f</em>-(2→1)-Fru-transfer ability (which produces 1-kestose), and instead has β-Fru<em>f</em>-(2→6)-Glc-transfer ability and produces neokestose. Its hydrolytic activity specific to the β-Fru<em>f</em>-(2↔1)-α-Glc<em>p</em> bond of neokestose then yields blastose [β-Fru<em>f</em>-(2→6)-Glc<em>p</em>]. The enzyme produces 0.4 M blastose from 1.0 M sucrose (80 % of the theoretical yield). The production system for blastose established here will contribute to the elucidation of the physiological functions of this disaccharide.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110500"},"PeriodicalIF":3.4,"publicationDate":"2024-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142058103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Semi-rational engineering of ω-transaminase for enhanced enzymatic activity to 2-ketobutyrate","authors":"Lili Zhang ,&nbsp;Yu Hong ,&nbsp;Jiapeng Lu ,&nbsp;Yi Wang ,&nbsp;Wei Luo","doi":"10.1016/j.enzmictec.2024.110505","DOIUrl":"10.1016/j.enzmictec.2024.110505","url":null,"abstract":"<div><p>Transaminases (EC 2.6.1.X, TAs) are important biocatalysts in the synthesis of chiral amines, and have significant value in the field of medicine. However, TAs suffer from low enzyme activity and poor catalytic efficiency in the synthesis of chiral amines or non-natural amino acids, which hinders their industrial applications. In this study, a novel TA derived from <em>Paracoccus pantotrophus</em> (<em>pp</em>TA) that was investigated in our previous study was employed with a semi-rational design strategy to improve its enzyme activity to 2-ketobutyrate. By using homology modeling and molecular docking, four surrounding sites in the substrate-binding S pocket were selected as potential mutational sites. Through alanine scanning and saturation mutagenesis, the optimal mutant V153A with significantly improved enzyme activity was finally obtained, which was 578 % higher than that of the wild-type <em>pp</em>TA (WT). Furthermore, the mutant enzyme <em>pp</em>TA-V153A also exhibited slightly improved temperature and pH stability compared to WT. Subsequently, the mutant was used to convert 2-ketobutyrate for the preparation of L-2-aminobutyric acid (L-ABA). The mutant can tolerate 300 mM 2-ketobutyrate with a conversion rate of 74 %, which lays a solid foundation for the preparation of chiral amines.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110505"},"PeriodicalIF":3.4,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of efficient amine transaminase and applicability in dual transaminases cascade for synthesis of L-phosphinothricin","authors":"Puhong Yi ,&nbsp;Mengdan Liu ,&nbsp;Yuhua Hao ,&nbsp;Ziwen Wang ,&nbsp;Hanlin Liu ,&nbsp;Xue Cai ,&nbsp;Feng Cheng ,&nbsp;Zhiqiang Liu ,&nbsp;Yaping Xue ,&nbsp;Liqun Jin ,&nbsp;Yuguo Zheng","doi":"10.1016/j.enzmictec.2024.110501","DOIUrl":"10.1016/j.enzmictec.2024.110501","url":null,"abstract":"<div><p>L-phosphinothricin (L-PPT) is the most popular broad-spectrum and highly effective herbicide. Transaminases (TAs) play a pivotal role in asymmetric synthesis of L-PPT, yet encounter the challenge of unfavorable reaction equilibrium. In this study, the novel dual transaminases cascade system (DTCS) was introduced to facilitate the synthesis of L-PPT. The specific amine transaminase BdATA, originating from <em>Bradyrhizobium diazoefficiens</em> ZJY088, was screened and identified. It exhibited remarkable activity, good stability, and required only 2.5 equivalents of isopropylamine to transform pyruvate effectively. By coupling BdATA with previously reported SeTA to construct the DTCS for pyruvate removal <em>in situ</em>, the L-PPT yield escalated from 37.37 % to 85.35 %. Three advantages of the DTCS were presented: the removal of pyruvate alleviated by-product inhibition, the use of isopropylamine reduced reliance on excess L-alanine, and no demand for expensive cofactors like NAD(P)H. It demonstrated an innovative idea for addressing the challenges associated with transaminase-mediated synthesis of L-PPT.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110501"},"PeriodicalIF":3.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142083411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A directional electrode separator improves anodic biofilm current density in a well-mixed single-chamber bioelectrochemical system","authors":"Md Monzurul Islam Anoy ,&nbsp;Eric Allen Hill ,&nbsp;Marci Ranae Garcia ,&nbsp;Won-Jun Kim ,&nbsp;Alexander S. Beliaev ,&nbsp;Haluk Beyenal","doi":"10.1016/j.enzmictec.2024.110502","DOIUrl":"10.1016/j.enzmictec.2024.110502","url":null,"abstract":"<div><p>In this study, a directional electrode separator (DES) was designed and incorporated into a single-chamber bioelectrochemical system (BES) to reduce migration and reoxidation of hydrogen. This issue arises when H₂, generated at the cathode, travels to the anode where anodic biofilms use H₂. To test the feasibility of our design, a 3D-printed BES reactor equipped with a DES was inoculated with anaerobic digestor granules and operated under fed-batch conditions using fermented corn stover effluent. The DES equipped reactor achieved significantly higher current densities (∼53 A/m²) compared to a conventional single-chamber BES without a separator (∼16 A/m²), showing a 3.3 times improvement. Control abiotic electrochemical experiments revealed that the DES exhibited significantly higher proton conductivity (456±127 µS/mm) compared to a proton exchange membrane (67±21 µS/mm) with a statistical significance of P=0.03. The DES also effectively reduced H₂ migration to the anode by 21-fold relative to the control. Overall, incorporating a DES in a single-chamber BES enhanced anodic current density by reducing H₂ migration to the anode.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110502"},"PeriodicalIF":3.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142098426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of a secondary palmitoleoyltransferase of lipid A in Vibrio parahaemolyticus","authors":"Danyang Huang ,&nbsp;Lingyan Chen ,&nbsp;Zhe Wang ,&nbsp;Fenfang He ,&nbsp;Xinrui Zhang ,&nbsp;Xiaoyuan Wang","doi":"10.1016/j.enzmictec.2024.110504","DOIUrl":"10.1016/j.enzmictec.2024.110504","url":null,"abstract":"<div><p>The detection of pathogenicity and immunogenicity in <em>Vibrio parahaemolyticus</em> poses a significant challenge due to its threat to human health and food safety, which is strongly correlated with lipid A. Lipid A, a critical component found in most Gram-negative bacteria, functions as a hydrophobic anchor for lipopolysaccharide. <em>V. parahaemolyticus</em> synthesizes multiple lipid A species with various secondary acyl chains. In this study, a secondary acyltransferase of lipid A encoded by <em>VP_RS08405</em> in <em>V. parahaemolyticus</em> was identified. Based on sequence alignment analysis, <em>V. parahaemolyticus VP_RS08405</em> has high homology to <em>E. coli lpxL</em>, <em>lpxM</em> and <em>lpxP</em> which encode the three secondary acyltransferases of lipid A. Therefore, <em>V. parahaemolyticus VP_RS08405</em> was cloned into pBAD33, and the resulting pB08405 was introduced in <em>E. coli</em> mutants WHL00 in which <em>lpxL</em> was deleted, WHM00 in which <em>lpxM</em> was deleted, WHP00 in which <em>lpxP</em> was deleted, and WH300 in which <em>lpxL</em>, <em>lpxM</em> and <em>lpxP</em> were deleted. The recombinant strains WHL00/pB08405, WHM00/pB08405, WHP00/pB08405, WH300/pB08405, as well as their vector controls, were grown at normal and low temperatures. Lipid A species were isolated from the above strains and analyzed by using high-performance liquid chromatography-tandem mass spectrometry and thin-layer chromatography. After comparing the secondary acyl alterations of lipid A from different recombinant strains, it is concluded that VP_RS08405 specifically catalyzed the addition of a palmitoleate to the 2′-position of lipid A and its activity is not temperature-sensitive. In addition, to determine the dependence of VP_RS08405 on Kdo, <em>VP_RS08405</em> was overexpressed in <em>E. coli</em> mutants WH001 in which <em>waaA</em> was deleted, and WH400 in which <em>waaA</em>, <em>lpxL</em>, <em>lpxM</em> and <em>lpxP</em> were deleted. Lipid A species were isolated from WH001/pB08405 and WH400/pB08405, and analyzed. The results show that the function of VP_RS08405 is Kdo-dependent. These findings provide a better understanding of the structural diversity of lipid A in <em>V. parahaemolyticus</em>.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110504"},"PeriodicalIF":3.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142077114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced glucose-1-phosphate production from corn stover using cellulases with reduced β-glucosidase activity via Trbgl1 gene knockout in Trichoderma reesei Rut C30","authors":"Xiaoqin Ran,&nbsp;Yushan Gao,&nbsp;Xiao He,&nbsp;Zancheng Wang,&nbsp;Yi Mo,&nbsp;Yonghao Li","doi":"10.1016/j.enzmictec.2024.110503","DOIUrl":"10.1016/j.enzmictec.2024.110503","url":null,"abstract":"<div><p>The scarcity of cellulases with low β-glucosidase activity poses a significant technological challenge in precisely controlling the partial hydrolysis of lignocellulose to cellobiose, crucial for producing high-value chemicals such as starch, inositol, and NMN. <em>Trichoderma reesei</em> is a primary strain in cellulase production. Therefore, this study targeted the critical β-glucosidase gene, <em>Trbgl1</em>, resulting in over an 86 % reduction in β-glucosidase activity. However, cellulase production decreased by 19.2 % and 20.3 % with lactose or cellulose inducers, respectively. Notably, transcript levels of cellulase genes and overall yield remained unaffected with an inducer containing sophorose. This indicates that β-glucosidase BGL1 converts lactose or cellulose to sophorose through transglycosylation activity, inducing cellulase gene transcription. The resulting enzyme cocktail, comprising recombinant cellulase and cellobiose phosphorylase, was applied for corn stover hydrolysis, resulting in a 24.3 % increase in glucose-1-phosphate yield. These findings provide valuable insights into obtaining enzymes suitable for the high-value utilization of lignocellulose.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110503"},"PeriodicalIF":3.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142087989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing the thermal stability and activity of zearalenone lactone hydrolase to promote zearalenone degradation via semi-rational design","authors":"Xue Jiang ,&nbsp;Sana Tehreem ,&nbsp;Kashif Rahim ,&nbsp;Meixing Wang ,&nbsp;Pan Wu ,&nbsp;Guimin Zhang","doi":"10.1016/j.enzmictec.2024.110499","DOIUrl":"10.1016/j.enzmictec.2024.110499","url":null,"abstract":"<div><p>Zearalenone (ZEN) is a fungal toxin produced by <em>Fusarium exospore</em>, which poses a significant threat to both animal and human health due to its reproductive toxicity. Removing ZEN through ZEN lactonase is currently the most effective method reported, however, all published ZEN lactonases suffer from the poor thermal stability, losing almost all activity after 10 min of treatment at 55℃. In this study, we heterologously expressed ZHD11A from <em>Phialophora macrospora</em> and engineered it via semi-rational design. A mutant I160Y-G242S that can retain about 40 % residual activity at 55℃ for 10 min was obtained, which is the most heat-tolerant ZEN hydrolase reported to date. Moreover, the specific activity of the I160Y-G242S was also elevated 2-fold compared to ZHD11A from 220 U/mg to 450 U/mg, which is one of the most active ZEN lactonses reported. Dynamics analysis revealed that the decreased flexibility of the main-chain carbons contributes to increased thermal stability and the improved substrate binding affinity and catalytic turnover contribute to enhanced activity of variant I160Y-G242S. In all, the mutant I160Y-G242S is an excellent candidate for the industrial application of ZEN degradation.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110499"},"PeriodicalIF":3.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling the crystal structure of thermostable dienelactone hydrolase exhibiting activity on terephthalate esters","authors":"Dnane Vieira Almeida ,&nbsp;Iara Ciancaglini ,&nbsp;Ana Luiza Hernandes Sandano ,&nbsp;Ellen K.B. Roman ,&nbsp;Viviane Brito Andrade ,&nbsp;Ana Bárbara Nunes ,&nbsp;Robson Tramontina ,&nbsp;Viviam Moura da Silva ,&nbsp;Frank Gabel ,&nbsp;Thamy L.R. Corrêa ,&nbsp;André Damasio ,&nbsp;João Renato Carvalho Muniz ,&nbsp;Fabio Marcio Squina ,&nbsp;Wanius Garcia","doi":"10.1016/j.enzmictec.2024.110498","DOIUrl":"10.1016/j.enzmictec.2024.110498","url":null,"abstract":"<div><p>Dienelactone hydrolase (DLH) is one of numerous hydrolytic enzymes with an α/β-hydrolase fold, which catalyze the hydrolysis of dienelactone to maleylacetate. The DLHs share remarkably similar tertiary structures and a conserved arrangement of catalytic residues. This study presents the crystal structure and comprehensive functional characterization of a novel thermostable DLH from the bacterium <em>Hydrogenobacter thermophilus</em> (<em>Ht</em>DLH). The crystal structure of the <em>Ht</em>DLH, solved at a resolution of about 1.67 Å, exhibits a canonical α/β-hydrolase fold formed by eight β-sheet strands in the core, with one buried α-helix and six others exposed to the solvent. The structure also confirmed the conserved catalytic triad of DHLs formed by Cys121, Asp170, and His202 residues. The <em>Ht</em>DLH forms stable homodimers in solution. Functional studies showed that <em>Ht</em>DLH has the expected esterase activity over esters with short carbon chains, such as <em>p-</em>nitrophenyl acetate, reaching optimal activity at pH 7.5 and 70 °C. Furthermore, <em>Ht</em>DLH maintains more than 50 % of its activity even after incubation at 90 °C for 16 h. Interestingly, <em>Ht</em>DLH exhibits catalytic activity towards polyethylene terephthalate (PET) monomers, including bis-1,2-hydroxyethyl terephthalate (BHET) and 1-(2-hydroxyethyl) 4-methyl terephthalate, as well as other aliphatic and aromatic esters. These findings associated with the lack of activity on amorphous PET indicate that <em>Ht</em>DLH has characteristic of a BHET-degrading enzyme. This work expands our understanding of enzyme families involved in PET degradation, providing novel insights for plastic biorecycling through protein engineering, which could lead to eco-friendly solutions to reduce the accumulation of plastic in landfills and natural environments.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110498"},"PeriodicalIF":3.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142047994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Substrate specificity of commercial lipases activated by a hydration–aggregation pretreatment in anhydrous esterification reactions","authors":"Takashi Kuroiwa,&nbsp;Maho Katayama,&nbsp;Kazuki Uemoto,&nbsp;Akihiko Kanazawa","doi":"10.1016/j.enzmictec.2024.110497","DOIUrl":"10.1016/j.enzmictec.2024.110497","url":null,"abstract":"<div><p>Substrate specificity in non-aqueous esterification catalyzed by commercial lipases activated by hydration–aggregation pretreatment was investigated. Four microbial lipases from <em>Rhizopus japonicus</em>, <em>Burkholderia cepacia</em>, <em>Rhizomucor miehei</em>, and <em>Candida antarctica</em> (fraction B) were used to study the effect of the carbon chain length of saturated fatty acid substrates on the esterification activity with methanol in <em>n</em>-hexane. Hydration–aggregation pretreatment had an activation effect on all lipases used, and different chain length dependencies of esterification activity for lipases from different origins were demonstrated. The effects of various acidic substrates with different degrees of unsaturation, aromatic rings, and alcohol substrates with different carbon chain lengths on esterification activity were examined using <em>R. japonicus</em> lipase, which demonstrated the most remarkable activity enhancement after hydration–aggregation pretreatment. Furthermore, in the esterification of myristic acid with methanol catalyzed by the hydrated–aggregated <em>R. japonicus</em> lipase, maximum reaction rate (5.43 × 10⁻⁵ mmol/(mg-biocat min)) and Michaelis constants for each substrate (48.5 mM for myristic acid, 24.7 mM for methanol) were determined by kinetic analysis based on the two-substrate Michaelis-Menten model.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"180 ","pages":"Article 110497"},"PeriodicalIF":3.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141998286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}