Priscila Esteves de Faria , Gabriel Stamato Nunes , Gabriela Coelho Brêda , Erika Cristina Gonçalves Aguieiras , Maria Beatriz Santos Mota , Leticia Dobler , Denise Maria Guimarães Freire , Rodrigo Volcan Almeida , Rafael Dias Mesquita
{"title":"Unveiling six novel CALB-like lipases using genome-centric and patent-driven prospection","authors":"Priscila Esteves de Faria , Gabriel Stamato Nunes , Gabriela Coelho Brêda , Erika Cristina Gonçalves Aguieiras , Maria Beatriz Santos Mota , Leticia Dobler , Denise Maria Guimarães Freire , Rodrigo Volcan Almeida , Rafael Dias Mesquita","doi":"10.1016/j.enzmictec.2024.110525","DOIUrl":"10.1016/j.enzmictec.2024.110525","url":null,"abstract":"<div><div>Lipases present biotechnological applications in various industrial sectors due to their ability to perform multiple biochemical reactions. However, the high cost sometimes discourages their potential uses, besides the extensive number of patents involving them. One of the most utilized and researched lipases is <em>Candida antarctica</em> lipase B (CALB), known for its versatility, encompassing enantioselectivity, thermostability, and a wide range of substrates. Therefore, finding new CALB-like lipases is an interesting strategy to enable the implementation of biocatalysts, especially if intellectual property analysis is included. The present study identified and produced six CALB-like enzymes without patent protection, with differences in pocket amino acids and substrate specificity. We conducted genomic searches in almost 7000 Fungal genomes, identifying over 1500 unique CALB homolog candidates. The phylogenetic and intellectual property analysis filtered those results into a few sequences without protection that were very similar to CALB. One cloned lipase had a lower hydrophobicity at the pocket entrance and preferred the C4 p-nitrophenyl ester as substrate. Another had a wider opening and more polar pocket, showing no preference. These results identified new patent-free lipases with conserved essential catalytic elements and diverse substrate specificity due to variations in the catalytic pocket. These enzymes can be the starting point for biocatalyst innovation with potential applications in diverse biotechnological areas.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110525"},"PeriodicalIF":3.4,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432153","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 production of adipic acid from 6-hydroxyhexanoic acid for biocatalytic upcycling of polycaprolactone","authors":"Yu-Ri Oh , Young-Ah Jang , Gyeong Tae Eom","doi":"10.1016/j.enzmictec.2024.110521","DOIUrl":"10.1016/j.enzmictec.2024.110521","url":null,"abstract":"<div><div>To valorize waste polycaprolactone (PCL), one of the most widely used biodegradable plastics, into a value-added chemical, we upcycled 6-hydroxyhexanoic acid (6-HHA), the sole monomer of PCL, into adipic acid (AA) using a microbial method. Recombinant <em>Escherichia coli</em> strains expressing <em>chnD</em> (6-HHA dehydrogenase) and <em>chnE</em> (6-oxohexanoic acid dehydrogenase) genes from three bacteria were constructed, and all these strains successfully produced AA from 6-HHA. Among these, the <em>E. coli</em> strain harboring ChnDE genes from <em>Acinetobacter</em> strain SE19 (<em>E. coli</em> [pKK-AcChn]) showed the highest AA-producing ability. To increase the AA production titer, we optimized the culture temperature of this strain in flask culture and performed fed-batch fermentation in a 5 L bioreactor. After the fed-batch fermentation, the AA production titer increased to 15.6 g/L. As 6-HHA is a monomer of PCL, our results provide the groundwork for the development of a biocatalytic upcycling method of PCL.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110521"},"PeriodicalIF":3.4,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142424658","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}
Xi Wang , Chenzhi Zhuhuang , Yi He, Xiaolong Zhang, Yan Wang, Qinxue Ni, Youzuo Zhang, Guangzhi Xu
{"title":"Selective transformation of crocin-1 to crocetin-glucosyl esters by β-glucosidase (Lf18920) from Leifsonia sp. ZF2019: Insights from molecular docking and point mutations","authors":"Xi Wang , Chenzhi Zhuhuang , Yi He, Xiaolong Zhang, Yan Wang, Qinxue Ni, Youzuo Zhang, Guangzhi Xu","doi":"10.1016/j.enzmictec.2024.110522","DOIUrl":"10.1016/j.enzmictec.2024.110522","url":null,"abstract":"<div><div>Crocetin di/mono-glucosyl esters (crocin-4 and crocin-5) are rarely distributed in nature, limiting their potential applications in the food and pharmaceutical industries. In the present study, a novel GH3 family β-glucosidase Lf18920 was identified from <em>Leifsonia</em> sp. ZF2019, which selectively hydrolyzed crocin-1 (crocetin di-gentiobiosyl ester) to crocin-5 and crocin-4, but not to its aglycone, crocetin. Under the optimal condition of 40 °C and pH 6.0 for 120 min, Lf18920 almost completely hydrolyzed crocin-1, yielding 73.50±5.66 % crocin-4 and 16.19±1.38 % crocin-5. Molecular docking and point mutation studies revealed that Lf18920 formed a narrow binding channel that facilitated crocin-1 binding. Five single amino acid variants (D50A, D53A, W274A, G420A, and Q421A) were constructed, all of which showed reduced hydrolytic activity. Mutations at D50 and D53, located distal to the active site, increased binding energy and decreased hydrolytic activity, while mutations at W274, G420, and Q421, proximal to the active site, disrupted hydrolytic function. These findings suggest that the narrow binding channel and specific enzyme-substrate interactions are crucial for Lf18920’s selective hydrolytic activity. Overall, this study is the first to report a β-glucosidase capable of selectively transforming crocin-1 to crocetin di/mono-glucosyl esters, offering potential for synthesizing crocin-4 and crocin-5.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110522"},"PeriodicalIF":3.4,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388978","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}
Idamaria Romakkaniemi, Johanna Panula-Perälä, Juha Ahola, Marja Mikola, Juha Tanskanen
{"title":"Lignin-based monophenolic model compounds in L-tyrosine derivative synthesis via tyrosine phenol lyase","authors":"Idamaria Romakkaniemi, Johanna Panula-Perälä, Juha Ahola, Marja Mikola, Juha Tanskanen","doi":"10.1016/j.enzmictec.2024.110519","DOIUrl":"10.1016/j.enzmictec.2024.110519","url":null,"abstract":"<div><div>Tyrosine phenol lyase (TPL) synthesises L-tyrosine derivatives from monophenols, pyruvate and ammonia. Production of such high-value aromatic chemicals from biomass-derived raw materials is of great interest. In this study, six monophenols (guaiacol, phenol, o-cresol, m-cresol, catechol and syringol) were chosen based on the structure of lignin and were studied as substrates in the enzymatic reaction. Single monophenol reactions (SMR) and binary monophenol reactions (BMR) with guaiacol were carried out. TPL-M379V was found to be selective towards guaiacol (84.5 % conv.). The highest single activity was measured towards phenol (93.9 % conv.). However, the enzyme preferred guaiacol over phenol in the BMRs. Syringol was found to be inert in the reaction, whereas catechol had an inhibitory effect on the enzymatic reaction, in addition to causing degradation of all the substrates in the medium. Doubling the guaiacol concentration in the SMR did not significantly increase the production of 3-O-methyldopa (conv. 45.9 %). However, in the binary reaction systems the total monophenol conversions were higher with guaiacol and phenol (total 62.4 %) or o-cresol (total 57.1 %). This indicates possible substrate/product specific inhibition. The study provides new data on activity, selectivity and inhibitory effects of monophenols in the synthetic reaction catalysed by TPL-M379V, especially in mixed-substrate reactions.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110519"},"PeriodicalIF":3.4,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142380313","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":"Protein engineering of an alkaline protease from Bacillus licheniformis (BLAP) for efficient and specific chiral resolution of the racemic ethyl tetrahydrofuroate","authors":"Xinjun Yu , Yichao Li , Zhaoxia Qian, Litian Wei, Jing Xie, Meijun Tong, Yinjun Zhang","doi":"10.1016/j.enzmictec.2024.110523","DOIUrl":"10.1016/j.enzmictec.2024.110523","url":null,"abstract":"<div><div>Enzymatic resolution of ethyl tetrahydrofuroate to produce (<em>S</em>)-2-ethyl tetrahydrofuroate and (<em>R</em>)-2-tetrahydrofuroic acid is a green biomanufacturing strategy. However, enzymatic activity and selectivity are still limiting factors of their industrial applications and development. In previous study, we incidentally found that a <em>Bacillus licheniformis</em> alkaline protease (BLAP), not a lipase, could specifically resolve ethyl tetrahydrofuroate to produce (<em>S</em>)-2-ethyl tetrahydrofuroate and (<em>R</em>)-2-tetrahydrofuroic acid. In this study, the point-saturation-mutation libraries based on the seven amino acid sites (L105, I113, P114, L115, V309, Y310, and M326) were constructed and screened using the molecular docking technology. It was found that activity of the mutant BLAP<sup>Y310E</sup> reached 182.78 U/mL with high stereoselectivity, 3.14 times higher than that of the wild-type BLAP. Further simulated mutation analysis showed that the Y310E mutation increased the distance from the substrate ligand to the binding pocket from 2.3 Å to 4.5 Å, reducing steric hindrance to the active center. Under the optimal conditions and after 3.5 h of reaction catalyzed by BLAP<sup>Y310E</sup>, 200 mM ethyl tetrahydrofuroate was converted to (<em>S</em>)-2-ethyl tetrahydrofuroate and (<em>R</em>)-2-tetrahydrofuroic acid with the <em>ee</em> values of 99.9 % and 68.63 %, respectively. The enantiomeric ratio of BLAP<sup>Y310E</sup> was 105.5, which was 30.23 times higher than that of BLAP. This study advances the comprehension of protease activity and selectivity mechanisms in resolving ester substances and lays a robust foundation for the industrial production of the optically pure (<em>S</em>)-2-ethyl tetrahydrofuroate and (<em>R</em>)-2-tetrahydrofuroic acid via biological enzymatic methods.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110523"},"PeriodicalIF":3.4,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388977","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}
Yu-Chen Xie , Zhi-Wei Ye , Jv-Liang Dai , Hao-Hong Chen , Jian-Guo Jiang
{"title":"Characterization of lycopene β-cyclase from Dunaliella bardawil for enhanced β-carotene production and salt tolerance","authors":"Yu-Chen Xie , Zhi-Wei Ye , Jv-Liang Dai , Hao-Hong Chen , Jian-Guo Jiang","doi":"10.1016/j.enzmictec.2024.110520","DOIUrl":"10.1016/j.enzmictec.2024.110520","url":null,"abstract":"<div><div><em>Dunaliella</em> can accumulate more β-carotene (10 % or even more of the dry weight of cells) than any other species. Lycopene β-cyclase (LcyB) is the key enzyme in the catalysis of lycopene to β-carotene. In the present research, we used <em>Escherichia coli</em> BL21 (DE3) as host to construct two different types of engineering bacteria, one expressing the <em>D. bardawil</em> LcyB and the other expressing the orthologue <em>Erwinia uredovora</em> crtY. The catalytic ability of LcyB and CrtY were evaluated by comparing the β-carotene yields of the two <em>E. coli</em> BL21(DE3) strains, whose salt tolerance was simultaneously compared by cultivated them under different NaCl concentrations (1 %, 2 %, and 4 %). We also interfered with the <em>LcyB</em> gene to investigate the effect of <em>LcyB</em> in <em>D. bardawil</em>. Results displayed that the β-carotene yield of the LcyB-transformant significantly increased by about 48 % compared with the crtY-transformant. Additionally, <em>LcyB</em> was verified to be able to enhance the salt tolerance of <em>E. coli</em> BL21 (DE3). It is concluded that <em>D. bardawil</em> LcyB not only has better catalytic ability but also is able to confer salt tolerance to cells. Interfering <em>D. bardawil LcyB</em> induced the low expression of LcyB and the changes of growth and carotenoids metabolism in <em>D. bardawil.</em></div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110520"},"PeriodicalIF":3.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142388976","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}
Hee-Won Ahn , Jetendra Kumar Roy , Jaeick Lee , Mi-Jin Lee , Sang-Ho Yoo , Young-Wan Kim
{"title":"Action pattern of Sulfolobus O-α-glycoligase for synthesis of highly water soluble resveratrol 3,4′-α-diglucoside","authors":"Hee-Won Ahn , Jetendra Kumar Roy , Jaeick Lee , Mi-Jin Lee , Sang-Ho Yoo , Young-Wan Kim","doi":"10.1016/j.enzmictec.2024.110518","DOIUrl":"10.1016/j.enzmictec.2024.110518","url":null,"abstract":"<div><div>This study presents the enzymatic synthesis of resveratrol-3,4′-O-α-diglucoside (RDG) using a hyperactive O-α-glycoligase (MalA-D416R/Q450S) and α-glucopyranosyl fluoride as the donor substrate. The transglycosylation rate for resveratrol by MalA-D416R/Q450S was maximized in 100 mM Tris-HCl (pH 9.5) containing 20 % DMSO at 45°C. Because the p<em>K</em><sub>a</sub> of the 4′-OH group of resveratrol is lower than that of the 3-OH group, the 4′-OH group is more nucleophilic at the alkaline pH, leading to a preference for glycosylation at the 4′-OH site rather than the 3-OH site. This preference makes resveratrol 3-O-α-glucoside (R3G) as the more efficient acceptor than resveratrol 4′-O-α-glucoside (R4′G), resulting in negligible production of resveratrol 3-O-α-glucoside (R3G) due to its complete consumption in the second transglycosylation reaction when using a 2:1 ratio of donor to acceptor substrates. From a preparative scale reaction, R4′G and RDG were isolated with yields of 41.2 % and 43.3 %, respectively. The water solubility of RDG exceeded 1.67 M, which represents more than a 9,800-fold improvement compared to resveratrol. In a hydrolysis experiment using intestinal α-glycosidase from rat, the α-glucosides of resveratrol (R4′G and RDG) were completely deglycosylated to the aglycone.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110518"},"PeriodicalIF":3.4,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142328131","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}
Alex D. Gonzalez-Vasquez , El Siar Hocine , Marcela Urzúa , Javier Rocha-Martin , Roberto Fernandez-Lafuente
{"title":"Changes in ficin specificity by different substrate proteins promoted by enzyme immobilization","authors":"Alex D. Gonzalez-Vasquez , El Siar Hocine , Marcela Urzúa , Javier Rocha-Martin , Roberto Fernandez-Lafuente","doi":"10.1016/j.enzmictec.2024.110517","DOIUrl":"10.1016/j.enzmictec.2024.110517","url":null,"abstract":"<div><div>Ficin extract has been immobilized using different supports: glyoxyl and Aspartic/1,6 hexamethylenediamine (Asp/HA) agarose beads. The latter was later submitted to glutaraldehyde modification to get covalent immobilization. The activities of these 3 kinds of biocatalysts were compared utilizing 4 different substrates, casein, hemoglobin and bovine serum albumin and benzoyl-arginine-p-nitroanilide at pH 7 and 5. Using glyoxyl-agarose, the effect of enzyme-support reaction time on the activity versus the four substrates at both pH values was studied. Reaction time has been shown to distort the enzyme due to an increase in the number of covalent support-enzyme bonds. Surprisingly, for all the substrates and conditions the prolongation of the enzyme-support reaction did not imply a decrease in enzyme activity. Using the Asp/HA supports (with different amount of HA) differences in the effect on enzyme activity versus the different substrates are much more significant, while with some substrates the immobilization produced a decrease in enzyme activity, with in other cases the activity increased. These different effects are even increased after glutaraldehyde treatment. That way, the conformational changes induced by the biocatalyst immobilization or the chemical modification fully altered the enzyme protein specificity. This may also have some implications when following enzyme inactivation.</div></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110517"},"PeriodicalIF":3.4,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0141022924001248/pdfft?md5=4a8c2db0aa168bda301afda3b77f7953&pid=1-s2.0-S0141022924001248-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142312640","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":"Poly(3-hydroxybutyrate) production for food packaging from biomass derived carbohydrates by cupriavidus necator DSM 545","authors":"Gianfrancesco Russo , Paola Scocca , Mattia Gelosia , Giacomo Fabbrizi , Tommaso Giannoni , Stefania Urbani , Sonia Esposto , Andrea Nicolini","doi":"10.1016/j.enzmictec.2024.110516","DOIUrl":"10.1016/j.enzmictec.2024.110516","url":null,"abstract":"<div><p>The extensive utilization of conventional plastics has resulted in a concerning surge in waste. A potential solution lies in biodegradable polymers mostly derived from renewable sources. <em>Cupriavidus necator</em> DSM 545 is a microorganism capable, under stress conditions, of intracellularly accumulating Poly(3-hydroxybutyrate) (PHB), a bio-polyester. This study aimed to identify optimal conditions to maximize the intracellular accumulation of PHB and its global production using natural media obtained by processing lignocellulosic residues of cardoon, a low-cost feedstock. An intracellular PHB accumulation was observed in all of the tested media, indicating a metabolic stress induced by the lack of macronutrients. Increasing C/N ratios led to a significant decrease in cellular biomass and PHB production. Furthermore <em>C. necator</em> DSM 545 was incapable of consuming more than 25 g/L of supplied monosaccharides. Surprisingly, in the samples supplied with 60 % of the pentose-rich liquid fraction, complete consumption of xylose was observed. This result was also confirmed by subsequent tests using Medium 1 growth media containing xylose as the sole carbon source. Using a diluted medium with a C/N ratio of 5, a PHB production of 5.84 g/L and intracellular PHB accumulation of 77 % w/w were respectively achieved. Finally, comparative shelf-life tests conducted against conventional pre-packaging materials in PP suggested that PHB films performed similarly in preserve ready-to-eat products.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110516"},"PeriodicalIF":3.4,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0141022924001236/pdfft?md5=c85d42688356aef8de5e917227dcb749&pid=1-s2.0-S0141022924001236-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142271641","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}
Yuhan Wei , Wei Xu , Wenli Zhang , Penka Petrova , Kaloyan Petrov , Dawei Ni , Wanmeng Mu
{"title":"Characterization of Runella zeae D-mannose 2-epimerase and its expression in Bacillus subtilis for D-mannose production from D-glucose","authors":"Yuhan Wei , Wei Xu , Wenli Zhang , Penka Petrova , Kaloyan Petrov , Dawei Ni , Wanmeng Mu","doi":"10.1016/j.enzmictec.2024.110506","DOIUrl":"10.1016/j.enzmictec.2024.110506","url":null,"abstract":"<div><p>D-Mannose 2-epimerase (MEase) catalyzes the bioconversion between D-glucose and D-mannose. It is an important potential biocatalyst for large-scale production of D-mannose, a functional monosaccharide used in pharmaceutical and food industries. In this study, a new microbial MEase was characterized from <em>Runella zeae</em> DSM 19591. The enzyme was purified by one-step nickel-affinity chromatography and determined to be a dimeric protein with two identical subunits of approximately 86.1 kDa by gel filtration. The enzyme showed the highest activity at pH 8.0 and 40 °C, with a specific activity of 2.99 U/mg on D-glucose and 3.71 U/mg on D-mannose. The melting temperature (<em>T</em><sub>m</sub>) was 49.4 °C and the half-life was 115.14 and 3.23 h at 35 and 40 °C, respectively. The purified enzyme (1 U/mL) produced 115.7 g/L of D-mannose from 500 g/L of D-glucose for 48 h, with a conversion ratio of 23.14 %. It was successfully expressed in <em>Bacillus subtilis</em> WB600 via pP43NMK as the vector. The highest fermentation activity was 10.58 U/mL after fed-batch cultivation for 28 h, and the whole cells of recombinant <em>B. subtilis</em> produced 114.0 g/L of D-mannose from 500 g/L of D-glucose, with a conversion ratio of 22.8 %.</p></div>","PeriodicalId":11770,"journal":{"name":"Enzyme and Microbial Technology","volume":"181 ","pages":"Article 110506"},"PeriodicalIF":3.4,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167248","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}