Enzyme and Microbial Technology最新文献

{"title":"Carbohydrate-active enzyme-catalyzed stereoselective glycosylation of complex natural product glycosides","authors":"Daijing Wei ,&nbsp;Jiawei Hu ,&nbsp;Xudong Wu ,&nbsp;Yi Li ,&nbsp;Wenlin Wu ,&nbsp;Ying Xu ,&nbsp;Xuefei Wang ,&nbsp;Yinggang Luo","doi":"10.1016/j.enzmictec.2025.110589","DOIUrl":"10.1016/j.enzmictec.2025.110589","url":null,"abstract":"<div><div>Natural products and their derivatives are precious resources with extensive applications in various industrial fields. Enzymatic glycosylation is an efficient approach for chemical structure diversification and biological activity alternation of natural products. Herein, we reported a stereoselective glycosylation of complex natural product glycosides catalyzed by two carbohydrate-active enzymes (CAZys). ASP OleD, a mutant of glycosyltransferase OleD from <em>Streptomyces antibioticus</em>, catalyzed an explicit <em>β</em>-1,x-linkage glycosylation of the OH group of the glycosyl moiety of the representative plant-derived complex natural product glycosides, protodioscin (<strong>1</strong>) and epimedin C (<strong>2</strong>), producing two complex glycoside derivatives. The glycoside hydrolase Δ27ThCGT, a truncated cyclodextrin glucanotransferase from <em>Thermoanaerobacter</em> sp., exhibited a definite <em>α</em>-1,x-linkage glycosylation of the OH group of the glycosyl moiety of the glycosides <strong>1</strong>, <strong>2</strong>, and astragaloside IV (<strong>3</strong>), generating four complex glycoside derivatives. The chemical structures and absolute configurations of these enzymatic glycosylation products were determined by analysis of their HRMS and NMR data. The present study expands the enzymatic glycosylation diversification of complex glycosides catalyzed by the CAZys.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"185 ","pages":"Article 110589"},"PeriodicalIF":3.4,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143046030","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":"Microbial synthesis of m-tyrosine via whole-cell biocatalysis","authors":"Vanna Nguyen,&nbsp;Ashley Tseng,&nbsp;Cui Guo,&nbsp;Mary Adwer,&nbsp;Yuheng Lin","doi":"10.1016/j.enzmictec.2025.110590","DOIUrl":"10.1016/j.enzmictec.2025.110590","url":null,"abstract":"<div><div><em>Meta</em>-tyrosine (<em>m</em>-tyrosine), a nonproteinogenic amino acid, has shown significant potential for applications as an herbicide in agriculture and for various medical uses. However, the natural abundance of <em>m</em>-tyrosine is very low, limiting its widespread use. In this study, we successfully achieved microbial production of <em>m</em>-tyrosine by establishing the <em>in vivo</em> enzyme activity of phenylalanine 3-hydroxylase (PacX from <em>Streptomyces coeruleoribudus</em>) in <em>E. coli</em>, which catalyzes the <em>meta</em>-hydroxylation of phenylalanine to produce <em>m</em>-tyrosine. Remarkably, PacX is capable of utilizing the native <em>E. coli</em> cofactor tetrahydromonapterin (MH4) for its hydroxylation activity. The integration of a non-native MH4 regeneration system significantly improved the bioconversion efficiency, resulting in the accumulation of <em>m</em>-tyrosine at a concentration of up to 368 mg/L. Additionally, we attempted to modify a well-characterized phenylalanine 4-hydroxylase (P4H) from <em>Xanthomonas campestris</em> to alter its regioselectivity through protein engineering. Remarkably, a double mutant (F184C/G199T) successfully shifted the enzyme’s hydroxylation specificity from the <em>para-</em> to the <em>meta-</em>position, demonstrating the feasibility of altering the regioselectivity of aromatic amino acid hydroxylases (AAAHs). To the best of our knowledge, this is the first report of microbial production of <em>m</em>-tyrosine through whole-cell biocatalysis.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"185 ","pages":"Article 110590"},"PeriodicalIF":3.4,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143058402","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":"Development of translationally active cell lysates from different filamentous fungi for application in cell-free protein synthesis","authors":"Stephanie Friedrich ,&nbsp;Marina Schramm ,&nbsp;Jan Kiebist ,&nbsp;Kai-Uwe Schmidtke ,&nbsp;Katrin Scheibner","doi":"10.1016/j.enzmictec.2025.110588","DOIUrl":"10.1016/j.enzmictec.2025.110588","url":null,"abstract":"<div><div>There is an enormous potential for cell-free protein synthesis (CFPS) systems based on filamentous fungi in view of their simple, fast and mostly inexpensive cultivation with high biomass space-time yields and in view of their catalytic capacity.</div><div>In 12 of the 22 different filamentous fungi examined, <em>in vitro</em> translation of at least one of the two reporter proteins GFP and firefly luciferase was detected. The lysates showing translation of a reporter protein usually were able to synthesize a functional cell-free expressed unspecific peroxygenase (UPO) from the basidiomycete <em>Cyclocybe</em> (<em>Agrocybe) aegerita.</em></div><div>For the most promising candidate <em>Neurospora crassa</em>, the influence of different conditions of cultivation and lysate preparation on <em>in vitro</em> translation of the reporter proteins was investigated and optimized. In general, the greatest improvements in the translational activity were achieved by the choice of the growth medium, the addition of organic nitrogen being most beneficial. Optimizing the culture and preparation conditions of the <em>N. crassa</em> platform improved protein yield of the original lysate by a factor of 25 for firefly luciferase and 17 for GFP, respectively. In addition to the reporter proteins, the aforementioned UPO as well as a functional UPO from <em>Aspergillus niger</em> were cell-free expressed using the different lysates from <em>N. crassa</em>.</div><div>CFPS with fungal lysates opens the door to expressing UPOs in high throughput and in parallel, for example to optimize synthesis conditions or adapt catalyst properties. The presented method proves the general potential of fungal lysates for application in cell-free syntheses.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"185 ","pages":"Article 110588"},"PeriodicalIF":3.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143051971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pylb-based overexpression of cytochrome P450 in Bacillus subtilis 168","authors":"Thanaporn Wichai ,&nbsp;Sarintip Sooksai ,&nbsp;Sajee Noitang ,&nbsp;Alisa S. Vangnai ,&nbsp;Panaya Kotchaplai","doi":"10.1016/j.enzmictec.2025.110587","DOIUrl":"10.1016/j.enzmictec.2025.110587","url":null,"abstract":"<div><div>Inducer-free expression systems are promising tools for biorefinery because they can reduce the reliance on inducers, reducing production costs and simplifying processes. Owing to their broad range of substrate structures and catalytic reactions, cytochrome P450s are promising biocatalysts to produce value-added compounds. However, unsuitable levels of cytochrome P450 expression could result in cell stress, affecting the efficiency of the biocatalyst. Here, we assessed the potential of Pylb, a reported growth-phase-dependent promoter derived from <em>Bacillus subtilis</em> 168, to develop an inducer-free expression system, especially cytochrome P450 expression, in <em>B. subtilis</em>, a key workhorse strain. Utilizing a green fluorescent protein (GFP) reporter, we observed differential expression patterns under the control of Pylb and the constitutive promoter P43 in recombinant <em>Escherichia coli</em> and <em>B. subtilis</em>. Recombinant <em>B. subtilis</em> cultivated at 37 °C showed 2.8-fold higher bacterial fluorescence compared to cultivation at 30 °C. Codon-optimized engineered P450-BM3, which can convert octane to octanols, was selected as a model cytochrome P450 in this study. In the Pylb-based system, the expression of cytochrome P450 in recombinant <em>B. subtilis</em> can be detected at 24 h and increases over time as shown by the purpald assay. The activity of the overexpressed P450 was confirmed by the conversion of octane to octanols. Within one hour, the resting cells of recombinant <em>B. subtilis</em> produced 0.15 ± 0.04 mM of 1-octanol and 0.31 ± 0.08 mM of 2-octanol. Overall, the inducer-free Pylb-based system developed here is a potential biocatalyst for biorefinery applications.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"185 ","pages":"Article 110587"},"PeriodicalIF":3.4,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143046032","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":"Unraveling the role of E. coli and calf intestinal alkaline phosphatase in calcium phosphate synthesis","authors":"Maria G. Chernysheva,&nbsp;Georgii S. Mikhailov,&nbsp;Daria-Maria V. Ratova,&nbsp;Ivan V. Mikheev,&nbsp;Gennadii A. Badun,&nbsp;Alexander L. Nikolaev","doi":"10.1016/j.enzmictec.2025.110586","DOIUrl":"10.1016/j.enzmictec.2025.110586","url":null,"abstract":"<div><div>The enzyme-catalyzed synthesis of calcium phosphate is a promising method for producing calcium-based nanomaterials for biomedical applications. The purpose of this work was to determine the type of phosphate that forms when alkaline phosphatase catalyzes the reaction, and to identify the role of natural biopolymers in calcium phosphate formation. In this research, we analyzed calcium phosphates that were synthesized in the presence of alkaline phosphatase from either <em>E. coli</em> or calf intestinal, analyzed the obtained nanoparticles and compared them by functional composition, elemental ratio, and morphology. Since all syntheses were performed in Tris buffer with the addition of MgCl₂, the final depleted hydroxyapatite incorporated magnesium. It was found that in the first 24 h, the reaction product form is determined by the enzyme source as well as the presence of other biopolymers (in particular, humic acid) in the reaction mixture. Hollow nanospheres of the depleted hydroxyapatite were obtained as a final product for both <em>E. coli</em> and calf-intestinal alkaline phosphatase during a 7-day reaction. When humic acid was added into the reaction mixture, separate spheres of the depleted hydroxyapatite were observed during a 24-h reaction. When Mg ions are present in the reaction mixture as a buffer component, they are evenly incorporated into the structure of the resulting calcium phosphate. The data obtained can be useful in understanding the calcification process of bioobjects and in applying the enzymatic method of calcium phosphate synthesis to biomedical applications.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"184 ","pages":"Article 110586"},"PeriodicalIF":3.4,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143022868","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":"Isolation of an endophytic yeast for improving the antibacterial activity of water chestnut Jiaosu: Focus on variation of microbial communities","authors":"khadija EI Galai ,&nbsp;Wenna Dai ,&nbsp;Cheng Qian ,&nbsp;Jing Ye ,&nbsp;Qin Zhang ,&nbsp;Mengdie Gao ,&nbsp;Xinyu Yang ,&nbsp;Yanbin Li","doi":"10.1016/j.enzmictec.2025.110584","DOIUrl":"10.1016/j.enzmictec.2025.110584","url":null,"abstract":"<div><div>Recent years have seen an increase in the development of functional Jiaosu products, including eco-friendly Jiaosu and antimicrobial healthcare fermentation products. As a result, research on the antibacterial activity of Jiaosu has attracted attention. In the present study, the endophytic yeast WCF016, which exhibits antibacterial activity against <em>Escherichia coli</em> and <em>Staphylococcus aureus</em>, was isolated from the peel of water chestnut and identified as <em>Candida sake</em> via morphological and phylogenetic analyses based on 26S rDNA D1/D2 region sequencing. Water chestnut Jiaosu with or without WCF016 inoculation exhibited similar flavor and physicochemical properties. However, inoculation significantly enhanced the antibacterial activity of water chestnut Jiaosu, especially in group D (inoculate of both fruit and vegetable enzyme starter and WCF016), which showed the largest diameter in its inhibition zone for both <em>E. coli</em> and <em>S. aureus</em>, reaching 25 ± 0 mm and 24 ± 1.0 mm. Moreover, inoculation with WCF016 influenced the abundance of the microbial community, especially <em>Lactiplantibacillus</em> and <em>Zygoascus</em>, which reached 51.76 % and 24.46 %, respectively, in group B (inoculated WCF016), thereby improving the antibacterial activity and flavor quality of the water chestnut Jiaosu. Notably, final pH, total sugar, and all organic acids effectively promoted fungal diversity and exhibited a positive correlation with most of the fungal genera. These results indicate that conditions conducive to the formation of organic acid-producing microbes and the synthesis of organic acids promote the antibacterial activity of Jiaosu.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"184 ","pages":"Article 110584"},"PeriodicalIF":3.4,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143002163","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":"Cell-free biocatalysis for co-production of nicotinamide mononucleotide and ethanol from Saccharomyces cerevisiae and recombinant Escherichia coli","authors":"Anoth Maharjan ,&nbsp;Mamata Singhvi ,&nbsp;Beom Soo Kim","doi":"10.1016/j.enzmictec.2025.110585","DOIUrl":"10.1016/j.enzmictec.2025.110585","url":null,"abstract":"<div><div>Cell-free enzyme systems have emerged as a promising approach for producing various biometabolites, offering several advantages over traditional whole-cell systems. This study presents an approach to producing nicotinamide mononucleotide (NMN) by combining a <em>Saccharomyces cerevisiae</em> cell-free enzyme with a recombinant <em>Escherichia coli</em> cell-free enzyme. The system leverages the ATP generated by yeast during ethanol fermentation to produce NMN in the presence of nicotinamide (NAM) as a substrate. The optimal cell-free enzyme concentration and substrate concentration were investigated to maximize NMN production. The results showed that combined cell-free enzymes led to increased NMN and ethanol yields, with a maximum production of 1.5 mM NMN (2.7-fold) and ethanol production of 0.45 g/L achieved (1.6-fold) compared to individual cell-free enzymes. Furthermore, the study demonstrated that the protein concentration affected NMN production, with optimal production achieved at 5 g/L. This study demonstrates the potential of integrating multiple metabolic pathways in a single cell-free system, paving the way for the development of more efficient and sustainable bioproduction processes.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"184 ","pages":"Article 110585"},"PeriodicalIF":3.4,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143002206","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":"Effect of the support alkyl chain nature in the functional properties of the immobilized lipases","authors":"Diandra de Andrades ,&nbsp;Pedro Abellanas-Perez ,&nbsp;Javier Rocha-Martin ,&nbsp;Fernando Lopez-Gallego ,&nbsp;Andrés R. Alcántara ,&nbsp;Maria de Lourdes Teixeira de Moraes Polizeli ,&nbsp;Roberto Fernandez-Lafuente","doi":"10.1016/j.enzmictec.2025.110583","DOIUrl":"10.1016/j.enzmictec.2025.110583","url":null,"abstract":"<div><div>Supports coated with amino-hexyl and amino octyl have been prepared from glyoxyl agarose beads and compared in their performance with octyl-agarose to immobilize lipases A and B from <em>Candida antarctica</em> (CALA and CALB). Immobilization courses were similar using all supports, but enzyme release was more difficult using the amino-alkyl supports suggesting a mixed interfacial activation/ionic exchange immobilization. The enzyme activity and specificity (using p-nitrophenyl propionate, triacetin and both isomers of methyl mandelate) greatly depended on the support. In many instances the enzymes immobilized on the new supports offered higher activities and enantiospecificity in the hydrolysis of both enantiomers of methyl mandelate (mainly using CALB). This was coupled to a lower enzyme stability using the new supports, even in the presence of high ionic strength, suggesting that the amphipathic could be responsible of the enzyme lower stability. Using CALB, it was possible to detect a higher exposition of the enzyme Trp groups to the medium by florescence spectra after its immobilization on the amino-alkyl-supports, correlating to the higher activity and lower stability results.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"184 ","pages":"Article 110583"},"PeriodicalIF":3.4,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143002160","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":"Biosynthesis of 2-phenylethanol from styrene using engineered Escherichia coli whole cells","authors":"Tianzhen Xiong ,&nbsp;Qiuyue Gao ,&nbsp;Wei Liu ,&nbsp;Wei Li ,&nbsp;Guangyan Fan","doi":"10.1016/j.enzmictec.2025.110582","DOIUrl":"10.1016/j.enzmictec.2025.110582","url":null,"abstract":"<div><div>2-Phenylethanol, an aromatic alcohol with a rose scent, is widely used in the cosmetics, food, and pharmaceutical industries. We designed an efficient multi-enzyme cascade pathway for production of 2-phenylethanol from styrene as the substrate. Initially, 2-phenylethanol was produced by overexpression of styrene monooxygenase A (<em>styA</em>), styrene monooxygenase B (<em>styB</em>), styrene oxide isomerase (<em>SOI</em>), alcohol dehydrogenase (<em>yahK</em>), and glucose dehydrogenase (<em>gdh</em>) in <em>Escherichia coli</em> to give 6.28 mM 2-phenylethanol. Subsequently, plasmids with different copy numbers were employed to balance the expression of pathway enzymes to produce 10.28 mM 2-phenylethanol, resulting in a 63.7 % increase in the final yield. Furthermore, the pH and temperature of the whole-cell conversion reaction were optimized, the optimum pH and temperature are 7.5 and 35℃, respectively. Finally, whole-cell conversion experiment was conducted, and the production of 2-phenylethanol reached 48.17 mM within 10 h. This study provides a theoretical and practical foundation for production of 2-phenylethanol.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"184 ","pages":"Article 110582"},"PeriodicalIF":3.4,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142970129","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":"Analysis of enzyme kinetics of fungal methionine synthases in an optimized colorimetric microscale assay for measuring cobalamin-independent methionine synthase activity","authors":"Noël Jung,&nbsp;Tomás Vellozo-Echevarría,&nbsp;Kristian Barrett,&nbsp;Anne S. Meyer","doi":"10.1016/j.enzmictec.2025.110581","DOIUrl":"10.1016/j.enzmictec.2025.110581","url":null,"abstract":"<div><div><em>Aspergillus</em> spp. and <em>Rhizopus</em> spp., used in solid-state plant food fermentations, encode cobalamin-independent methionine synthase activity (MetE, EC 2.1.1.14). Here, we examine the enzyme kinetics, reaction activation energies (<em>E</em>_a), thermal robustness, and structural folds of three MetEs from three different food-fermentation relevant fungi, <em>Aspergillus sojae, Rhizopus delemar</em>, and <em>Rhizopus microsporus,</em> and compare them to the MetE from <em>Escherichia coli.</em> We also downscaled and optimized a colorimetric assay to allow direct MetE activity measurements in microplates. The catalytic rates, <em>k</em>_cat, of the three fungal MetE enzymes on the methyl donor (<em>6S</em>)-5-methyl-tetrahydropteroyl-L-glutamate₃ ranged from 1.2 to 3.3 min⁻¹ and <em>K</em>_M values varied from 0.8 to 6.8 µM. The <em>k</em>_cat was lowest for the <em>R. delemar</em> MetE, but this enzyme also had the lowest <em>K</em>_M thus resulting in the highest <em>k</em>_cat/<em>K</em>_M of ∼1.4 min⁻¹ µM⁻¹ among the three fungal enzymes. The <em>k</em>_cat was higher for the <em>E. coli</em> enzyme, 12 min⁻¹, but <em>K</em>_M was 6.4 µM, resulting in <em>k</em>_cat/<em>K</em>_M of ∼1.9 min⁻¹ µM⁻¹. The <em>E</em>_a values of the fungal MetEs ranged from 52 to 97 kJ mole⁻¹ and were higher than that of the <em>E. coli</em> MetE (38.7 kJ mole ⁻¹). The predicted structural folds of the MetEs were very similar. <em>T</em>_m values of the fungal MetEs ranged from 41 to 54 °C, highest for the <em>A. sojae</em> enzyme (54 °C), lowest for the <em>R. delemar</em> (41 °C). At 30 °C, the half-lives of the three fungal enzymes varied significantly, with MetE from <em>A. sojae</em> having the longest (&gt; 600 min, <em>k</em>_D=0), and <em>R. delemar</em> the shortest (17 min). Knowledge of the kinetics of these enzymes is important for understanding methionine synthesis in fungi and a first step in promoting methionine synthesis in fungally fermented plant foods.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"184 ","pages":"Article 110581"},"PeriodicalIF":3.4,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143002202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}