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Zhengqiang Jiang - One of the best experts on this subject based on the ideXlab platform.
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A novel high maltose-forming α-amylase from Rhizomucor miehei and its application in the food industry
Food chemistry, 2019Co-Authors: Yu-chuan Wang, Qiaojuan Yan, Haijie Liu, Zhengqiang JiangAbstract:Abstract A novel α-amylase gene (RmAmyA) from Rhizomucor miehei was cloned and expressed in Pichia pastoris. RmAmyA showed 70% amino acid identity with the α-amylase from Rhizomucor pusillus. A high α-amylase activity of 29,794.2 U/mL was found through high cell density fermentation. The molecular mass of RmAmyA was determined to be 49.9 kDa via SDS-PAGE. RmAmyA was optimally active at 75 °C and pH 6.0, and it did not require Ca2+ to improve its activity. It exhibited broad substrate specificity towards amylose, amylopectin, soluble starch, pullulan, and cyclodextrins. High level of maltose (54%, w/w) was produced after liquefied starch was hydrolysed with RmAmyA for 16 h. Moreover, the addition of RmAmyA into Chinese steamed bread resulted in 7.7% increment in the specific volume, and 17.2% and 11.5% reduction in the chewiness and hardness, respectively. These results indicate that RmAmyA might be a potential candidate for applications in the food industry.
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Jiang Z: Biochemical characterization of a first fungal esterase from Rhizomucor miehei showing high efficiency of ester synthesis
2016Co-Authors: Yu Liu, Shaoqing Yang, Qiaojuan Yan, Xiaojie Duan, Zhengqiang JiangAbstract:Background: Esterases with excellent merits suitable for commercial use in ester production field are still insufficient. The aim of this research is to advance our understanding by seeking for more unusual esterases and revealing their characterizations for ester synthesis. Methodology/Principal Findings: A novel esterase-encoding gene from Rhizomucor miehei (RmEstA) was cloned and expressed in Escherichia coli. Sequence analysis revealed a 975-bp ORF encoding a 324-amino-acid polypeptide belonging to the hormone-sensitive lipase (HSL) family IV and showing highest similarity (44%) to the Paenibacillus mucilaginosus esterase/lipase. Recombinant RmEstA was purified to homogeneity: it was 34 kDa by SDS-PAGE and showed optimal pH and temperature of 6.5 and 45uC, respectively. The enzyme was stable to 50uC, under a broad pH range (5.0–10.6). RmEstA exhibited broad substrate specificity toward p-nitrophenol esters and short-acyl-chain triglycerols, with highest activities (1,480 U mg21 and 228 U mg21) for p-nitrophenyl hexanoate and tributyrin, respectively. RmEstA efficiently synthesized butyl butyrate (92 % conversion yield) when immobilized on AOT-based organogel. Conclusion: RmEstA has great potential for industrial applications. RmEstA is the first reported esterase from Rhizomucor miehei
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Biochemical Characterization of a Novel Acidic Exochitinase from Rhizomucor miehei with Antifungal Activity.
Journal of agricultural and food chemistry, 2016Co-Authors: Shaoqing Yang, Qiaojuan Yan, Zhengqiang Jiang, Jing WangAbstract:A novel chitinase gene (RmChi44) from Rhizomucor miehei was cloned and expressed in Escherichia coli as an intracellular soluble and active protein. The recombinant chitinase (RmChi44) was purified to homogeneity and biochemically characterized. The molecular mass of RmChi44 was estimated to be 44.6 kDa on SDS-PAGE. RmChi44 displayed an acidic pH optimum of 4.5 and was stable within pH 4.5-9.0. The optimal temperature of RmChi44 was found to be 50 °C. The Km values of RmChi44 for colloidal chitin and glycol chitin were 4.02 and 1.55 mg/mL, respectively. RmChi44 hydrolyzed colloidal chitin to yield mainly N-acetyl chitobiose, exhibiting an exotype cleavage pattern. Moreover, the enzyme displayed β-N-acetylglucosaminidase activity, splitting N-acetyl COSs with degree of polymerization (DP) 2-5 into their monomer. In addition, RmChi44 showed antifungal activity against some phytopathogenic fungi. This is the first report on an exochitinase showing β-N-acetylglucosaminidase activity and antifungal activity from Rhizomucor species.
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Genome sequence and transcriptome analyses of the thermophilic zygomycete fungus Rhizomucor miehei
BMC genomics, 2014Co-Authors: Peng Zhou, Shaoqing Yang, Qiaojuan Yan, Zhengqiang Jiang, Guoqiang Zhang, Shangwu Chen, Yanbin Tang, Bernard Henrissat, Chin-fu Chen, Bing ZhangAbstract:Background The zygomycete fungi like Rhizomucor miehei have been extensively exploited for the production of various enzymes. As a thermophilic fungus, R. miehei is capable of growing at temperatures that approach the upper limits for all eukaryotes. To date, over hundreds of fungal genomes are publicly available. However, Zygomycetes have been rarely investigated both genetically and genomically.
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Biochemical characterization of a first fungal esterase from Rhizomucor miehei showing high efficiency of ester synthesis.
PloS one, 2013Co-Authors: Yu Liu, Shaoqing Yang, Qiaojuan Yan, Xiaojie Duan, Zhengqiang JiangAbstract:Background Esterases with excellent merits suitable for commercial use in ester production field are still insufficient. The aim of this research is to advance our understanding by seeking for more unusual esterases and revealing their characterizations for ester synthesis. Methodology/Principal Findings A novel esterase-encoding gene from Rhizomucor miehei (RmEstA) was cloned and expressed in Escherichia coli. Sequence analysis revealed a 975-bp ORF encoding a 324-amino-acid polypeptide belonging to the hormone-sensitive lipase (HSL) family IV and showing highest similarity (44%) to the Paenibacillus mucilaginosus esterase/lipase. Recombinant RmEstA was purified to homogeneity: it was 34 kDa by SDS-PAGE and showed optimal pH and temperature of 6.5 and 45°C, respectively. The enzyme was stable to 50°C, under a broad pH range (5.0–10.6). RmEstA exhibited broad substrate specificity toward p-nitrophenol esters and short-acyl-chain triglycerols, with highest activities (1,480 U mg−1 and 228 U mg−1) for p-nitrophenyl hexanoate and tributyrin, respectively. RmEstA efficiently synthesized butyl butyrate (92% conversion yield) when immobilized on AOT-based organogel. Conclusion RmEstA has great potential for industrial applications. RmEstA is the first reported esterase from Rhizomucor miehei.
Allan Svendsen - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the dynamics of Rhizomucor miehei lipase at different temperatures.
Journal of biomolecular structure & dynamics, 1999Co-Authors: Günther H.j. Peters, Søren Toxvaerd, Kim Vilbour Andersen, Allan SvendsenAbstract:Abstract The dynamics of Rhizomucor miehei lipase has been studied by molecular dynamics simulations at temperatures ranging from 200–500K. Simulations carried out in periodic boundary conditions and using explicit water molecules were performed for 400 ps at each temperature. Our results indicate that conformational changes and internal motions in the protein are significantly influenced by the temperature increase. With increasing temperature, the number of internal hydrogen bonds decreases, while surface accessibility, radius of gyration and the number of residues in random coil conformation increase. In the temperature range studied, the motions can be described in a low dimensional subspace, whose dimensionality decreases with increasing temperature. Approximately 80% of the total motion is described by the first (i) 80 eigenvectors at T=200K, (ii) 30 eigenvectors at T=300K and (iii) 10 eigenvectors at T=400K. At high temperature, the α-helix covering the active site in the native Rhizomucor miehei l...
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Lipases from Rhizomucor miehei and Humicola lanuginosa: modification of the lid covering the active site alters enantioselectivity.
Journal of protein chemistry, 1993Co-Authors: Mats Holmquist, Mats Martinelle, Per Berglund, Ib Groth Clausen, Shamkant Anant Patkar, Allan Svendsen, Karl HultAbstract:The homologous lipases from Rhizomucor miehei and Humicola lanuginosa showed approximately the same enantioselectivity when 2-methyldecanoic acid esters were used as substrates. Both lipases prefer ...
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Theoretical studies of Rhizomucor miehei lipase activation
Protein engineering, 1993Co-Authors: Matin Norin, Allan Svendsen, Ole Olsen, Olle Edholm, Karl HultAbstract:Computational methods have been used to study the extensive conformational change of Rhizomucor miehei lipase upon activation. The present study considers the possible activation route, the energies involved and molecular interactions during the conformational change of the lipase in a hydrophobic environment. The conformational change was study by conventional molecular dynamics methods and with a combined molecular dynamics and mechanics protocol, in which the conformational change was stimulated by restrained Cα pseudotorsional angles in small steps between the two crystallographically observed positions of the lib
Alicia Baldessari - One of the best experts on this subject based on the ideXlab platform.
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promiscuous behavior of Rhizomucor miehei lipase in the synthesis of n substituted β amino esters
European Journal of Organic Chemistry, 2012Co-Authors: Leandro N. Monsalve, Florencia Gillanders, Alicia BaldessariAbstract:A mild and efficient procedure for the aza-Michael addition of amines to acrylates by using lipases as catalysts is reported. Various lipases, mono- and bifunctional amines, alkyl acrylates, and reaction parameters were studied. Under the optimal conditions, Rhizomucor miehei lipase showed high selectivity. It catalyzed the formation of the Michael monoadduct as the only product in high yield and purity. Moreover, when diamines were used as nucleophiles, the lipase catalyzed the addition of only one of the two amino groups, showing in this case high substrate specificity. This promiscuous and highly selective behavior displayed by Rhizomucor miehei lipase allowed us to obtain 22 N-substituted β-amino esters, 15 of them being new products.
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Promiscuous Behavior of Rhizomucor miehei Lipase in the Synthesis of N‐Substituted β‐Amino Esters
European Journal of Organic Chemistry, 2011Co-Authors: Leandro N. Monsalve, Florencia Gillanders, Alicia BaldessariAbstract:A mild and efficient procedure for the aza-Michael addition of amines to acrylates by using lipases as catalysts is reported. Various lipases, mono- and bifunctional amines, alkyl acrylates, and reaction parameters were studied. Under the optimal conditions, Rhizomucor miehei lipase showed high selectivity. It catalyzed the formation of the Michael monoadduct as the only product in high yield and purity. Moreover, when diamines were used as nucleophiles, the lipase catalyzed the addition of only one of the two amino groups, showing in this case high substrate specificity. This promiscuous and highly selective behavior displayed by Rhizomucor miehei lipase allowed us to obtain 22 N-substituted β-amino esters, 15 of them being new products.
Csaba Vágvölgyi - One of the best experts on this subject based on the ideXlab platform.
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A new β-glucosidase gene from the zygomycete fungus Rhizomucor miehei
Antonie van Leeuwenhoek, 2009Co-Authors: Miklós Takó, Csaba Vágvölgyi, Adél Tóth, László Nagy, Judit Krisch, Tamás PappAbstract:In this study, a β-glucosidase coding gene ( bgl ) of the zygomycete fungus Rhizomucor miehei has been cloned and characterized. The gene comprises a total of 2,826 bp including the coding sequence of a 717 amino acids length putative protein and 10 introns dispersed in the whole coding region. The putative N-and C-terminal catalytic domains (aa 68 to aa 274 and aa 358–601, respectively) were identified; the two domains are connected with a 84-amino-acids linker. The catalytic region showed an extensive sequence homology with other fungal β-glucosidases classified as family 3 glycoside hydrolases. The isolated Rhizomucor gene was expressed in the related fungus Mucor circinelloides . Transformant Mucor strains maintained the introduced plasmid in an autoreplicative manner and showed significantly higher cellobiase activity than the recipient strain.
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A new β-glucosidase gene from the zygomycete fungus Rhizomucor miehei
Antonie van Leeuwenhoek, 2009Co-Authors: Miklós Takó, Csaba Vágvölgyi, Adél Tóth, László Nagy, Judit Krisch, Tamás PappAbstract:In this study, a beta-glucosidase coding gene (bgl) of the zygomycete fungus Rhizomucor miehei has been cloned and characterized. The gene comprises a total of 2,826 bp including the coding sequence of a 717 amino acids length putative protein and 10 introns dispersed in the whole coding region. The putative N-and C-terminal catalytic domains (aa 68 to aa 274 and aa 358-601, respectively) were identified; the two domains are connected with a 84-amino-acids linker. The catalytic region showed an extensive sequence homology with other fungal beta-glucosidases classified as family 3 glycoside hydrolases. The isolated Rhizomucor gene was expressed in the related fungus Mucor circinelloides. Transformant Mucor strains maintained the introduced plasmid in an autoreplicative manner and showed significantly higher cellobiase activity than the recipient strain.
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Cloning of the Rhizomucor miehei 3-hydroxy-3-methylglutaryl-coenzyme A reductase gene and its heterologous expression in Mucor circinelloides
Antonie van Leeuwenhoek, 2009Co-Authors: Gyöngyi Lukács, Tamás Papp, Ferenc Somogyvári, Árpád Csernetics, Ildikó Nyilasi, Csaba VágvölgyiAbstract:In this study, the gene hmgR encoding the 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) was cloned and characterized in the zygomycete fungus Rhizomucor miehei. The hmgR gene comprises a total of 3,585 bp including the coding sequence of a 1,058 amino acids length putative protein and five introns (137, 83, 59, 60 and 69 bp in length) dispersed in the whole coding region. Southern hybridization analysis revealed that the gene is present only in one copy in the R. miehei genome. The isolated Rhizomucor gene was expressed in the related fungus, Mucor circinelloides . Transformants harbouring the Rhizomucor hmgR gene in an autoreplicative plasmid proved to be more tolerant to statins (e.g. lovastatin, simvastatin, and fluvastatin), the competitive inhibitors of the HMG-CoA reductase, than the original M. circinelloides strain. At the same time, heterologous expression of the Rhizomucor hmgR did not affect the carotenoid production of M. circinelloides .
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Differentiation of Rhizomucor species on the basis of their different sensitivities to lovastatin
Journal of clinical microbiology, 2004Co-Authors: Gyöngyi Lukács, Tamás Papp, Ildikó Nyilasi, Erzsébet Nagy, Csaba VágvölgyiAbstract:The opportunistic pathogens Rhizomucor pusillus and Rhizomucor miehei may be agents of frequently fatal mycotic diseases. In the present study, the susceptibilities of 27 clinical and environmental isolates of R. miehei and R. pusillus to lovastatin under different culturing conditions were investigated. Most of the R. miehei strains grew at lovastatin concentrations as high as 64 to 128 μg/ml. In contrast, the inhibitory effect of lovastatin on all of the R. pusillus strains was evident at lovastatin concentrations as low as 1 to 2 μg/ml. A simple and reliable method for species-level differentiation, based on the significantly higher sensitivity of R. pusillus to lovastatin than that of R. miehei, was elaborated. According this, on malt extract agar containing 6 μg of lovastatin/ml, R. pusillus is not able to produce colonies, while R. miehei will form compact colonies.
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Intraspecific variation in two species of Rhizomucor assessed by random amplified polymorphic DNA analysis.
Journal of basic microbiology, 2000Co-Authors: Mária Vastag, T. Papp, Zsolt Kasza, Csaba VágvölgyiAbstract:Twenty-three Rhizomucor isolates were characterized by random amplified polymorphic DNA-PCR (RAPD-PCR) with 10-bp oligonucleotide primers. These data were used for numerical analyses to obtain information on the intraspecific genetic polymorphism of Rhizomucor species. The genetic variability in Rhizomucor pusillus and Rhizomucor miehei isolates was found to differ; the latter revealed less intraspecific polymorphism. The different levels of genotypic diversity suggest a correlation with the different forms of mating behaviour of these species. Rhizomucor tauricus displayed amplification patterns similar to those of the investigated R. pusillus strains, reinforcing the assumption that R. tauricus does not represent a separate species. Characteristic RAPD markers allowing PCR-based species identification of Rhizomucor isolates were determined.
José V. Sinisterra - One of the best experts on this subject based on the ideXlab platform.
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Stereoselective oxidation of alcohols using whole cells of Rhizomucor miehei CECT 2749
Journal of Molecular Catalysis B-enzymatic, 2006Co-Authors: C. García-burgos, J.d. Carballeira, José V. SinisterraAbstract:The oxidation of hydrophobic secondary alcohols catalyzed by immobilized whole cells of Rhizomucor miehei CECT 2749 is described for the first time. The biotransformation was performed with the fungus as resting cells and as immobilized catalyst using agarose and agars from different algae genera as matrix. The immobilized biocatalyst shows specificity in the oxidation of de S enantiomer of 1-(2-furyl)-ethanol and in the oxidation of iso-menthol, while R-furylethanol (+)-menthol and neo-menthol were not oxidized.
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Rhizomucor miehei lipase as the catalyst in the resolution of chiral compounds: an overview
Chemistry and Physics of Lipids, 1998Co-Authors: Andrés R. Alcántara, Isidoro E De Fuentes, José V. SinisterraAbstract:Abstract Rhizomucor miehei lipase is probably the most used lipase obtained from fungi, even being used as a model for the determination of the structure of some other lipases due to the deep knowledge of its three dimensional structure. In this paper we present an overview of the use of this lipase for the obtention of homochiral compounds via hydrolytic and acyl transfer methodologies. The application for the resolution of both chiral carboxylic acids and alcohol is also presented.
