Use of polyethylenimine to produce immobilized lipase multilayers biocatalysts with very high volumetric activity using octyl-agarose beads: Avoiding enzyme release during multilayer production
Publication date: June 2020Source: Enzyme and Microbial Technology, Volume 137Author(s): Sara Arana-Peña, Nathalia S. Rios, Carmen Mendez-Sanchez, Yuliya Lokha, Luciana R.B. Gonçalves, Roberto Fernández-LafuenteAbstractA strategy to obtain biocatalysts formed by three enzyme layers has been designed using lipases A and B from Candida antarctica (CALA and CALB), the lipases from Rhizomucor miehei (RML) and Thermomyces lanuginosus (TLL), and the artificial chimeric phospholipase Lecitase Ultra (LEU). The enzymes were initially immobilized via interfacial activation on octyl-agarose beads, treated with polyethylenimine (PE...
Source: Enzyme and Microbial Technology - February 21, 2020 Category: Biotechnology Source Type: research
Use of polyethylenimine to produce immobilized lipase multilayers biocatalysts using octyl-agarose beads with very high volumetric activity: Avoiding enzyme release during multilayer production
Publication date: Available online 17 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Sara Arana-Peña, Nathalia S. Rios, Carmen Mendez-Sanchez, Yuliya Lokha, Luciana R.B. Gonçalves, Roberto Fernández-LafuenteAbstractA strategy to obtain biocatalysts formed by three enzyme layers has been designed using lipases A and B from Candida antarctica (CALA and CALB), the lipases from Rhizomucor miehei (RML) and Thermomyces lanuginosus (TLL), and the artificial chimeric phospholipase Lecitase Ultra (LEU). The enzymes were initially immobilized via interfacial activation on octyl-agarose beads, treated with polyethy...
Source: Enzyme and Microbial Technology - February 17, 2020 Category: Biotechnology Source Type: research
Phenotypic characterization and comparative genome analysis of two strains of thermophilic, anaerobic, cellulolytic-xylanolytic bacterium Herbivorax saccincola
Publication date: May 2020Source: Enzyme and Microbial Technology, Volume 136Author(s): Shimpei Aikawa, Phakhinee Thianheng, Sirilak Baramee, Umbhorn Ungkulpasvich, Chakrit Tachaapaikoon, Rattiya Waeonukul, Patthra Pason, Khanok Ratanakhanokchai, Akihiko KosugiAbstractThe genome sequences of thermophilic, anaerobic, and cellulolytic-xylanolytic bacterium Herbivorax saccincola strains A7 and GGR1 have recently been determined. Although both strains belong to the same species, A7 is alkaliphilic, non-endospore-forming, and ammonium-assimilating, whereas GGR1 is neutrophilic, endospore-forming, and weak-ammonium-assimilating....
Source: Enzyme and Microbial Technology - February 14, 2020 Category: Biotechnology Source Type: research
Biochemical characterization of a novel thermostable DFA I-forming inulin fructotransferases from Streptomyces peucetius subsp. caesius ATCC 27952
In this study, a novel DFA I-forming IFTase was identified and characterized from Streptomyces peucetius subsp. caesius ATCC 27952 (SpIFTase). The specific activity of SpIFTase was determined to be 420.84 ± 6.21 U mg-1 at pH 6.5 and 45 °C. The enzyme exhibited a prominent thermostability with a half-life of 70 min at 70 °C and a structural melting temperature (Tm) of 75.48 °C. The values of Km and kcat/Km of SpIFTase against inulin substrate were 3.08 mM and 199.09 mM-1 s-1, respectively. Furthermore, the catalytic residues were investigated by site-directed mutagenesis with an alanine scanning method. In...
Source: Enzyme and Microbial Technology - February 10, 2020 Category: Biotechnology Source Type: research
Regulation of Aureofuscin Production by the PAS-LuxR Family Regulator AurJ3M
Publication date: Available online 8 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Jing Yang, Dexin Xu, Wenchen Yu, Ruobing Hao, Jie WeiAbstractaurJ3M(GenBank:EU697915.1), a 579 bp gene, whose deduced product (192 amino acid) was found to have amino acid sequence homology with some bacterial regulatory proteins. Computer-assisted analysis showed that AurJ3M is PAS-LuxR family regulatory protein, it combines a PAS domain with a helix–turn–helix (HTH) motif of the LuxR type. Gene deletion of aurJ3M from theS.aureofuscus SYAU0709 through gene replacement with the apramycin resistance gene aac (3) IV and t...
Source: Enzyme and Microbial Technology - February 10, 2020 Category: Biotechnology Source Type: research
Engineering and optimization of phosphate-responsive phytase expression in Pichia pastoris yeast for phytate hydrolysis
Publication date: Available online 7 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Zhenming Xie, Wing-Ping Fong, Paul Wai-Kei TsangAbstractPhytate is the major storage form of phosphorus in plants. It is present in cereals and raw materials of vegetable origin used in animal and human diets. However, non-ruminant animals have little phytase activity in their guts and, therefore, cannot digest phytate. As a result, almost all dietary phytate is discharged into the environment, causing phosphorus pollution. Phytate is also considered as an “antinutrient” for its ability to form insoluble and stable compl...
Source: Enzyme and Microbial Technology - February 8, 2020 Category: Biotechnology Source Type: research
Engineered Bacillus subtilis harbouring gene of D-tagatose 3-epimerase for the bioconversion of D-fructose into D-psicose through fermentation
Publication date: Available online 4 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Jun Zhang, Chao Xu, Xiaoyan Chen, Xi Ruan, Yu Zhang, Huijuan Xu, Ying Guo, Jingliang Xu, Pengmei Lv, Zhongming WangAbstractD-psicose, as important rare sugar and epimer of D-fructose on the C-3 position, displays unique health benefits and physiological functions in various fields. The production of D-psicose is currently obtained via enzymatic bioconversion, mostly with of D-tagatose 3-epimerase. In the present study, the isomerization of D-fructose into D-psicose was achieved by constructing engineered food-grade Bacillus ...
Source: Enzyme and Microbial Technology - February 5, 2020 Category: Biotechnology Source Type: research
Phenotypic characterization of thermophilic, anaerobic, cellulolytic-xylanolytic bacterium Herbivorax saccincola by comparative genome analysis
Publication date: Available online 1 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Shimpei Aikawa, Phakhinee Thianheng, Sirilak Baramee, Umbhorn Ungkulpasvich, Chakrit Tachaapaikoon, Rattiya Waeonukul, Patthra Pason, Khanok Ratanakhanokchai, Akihiko KosugiAbstractThe genome sequences of thermophilic, anaerobic, and cellulolytic-xylanolytic bacterium Herbivorax saccincola strains A7 and GGR1 have recently been determined. Although both strains belong to the same species, A7 is alkaliphilic, non-endospore-forming, and ammonium-assimilating, whereas GGR1 is neutrophilic, endospore-forming, and non-ammonium-...
Source: Enzyme and Microbial Technology - February 2, 2020 Category: Biotechnology Source Type: research
Direct and selective enzymatic synthesis of trehalose unsaturated fatty acid diesters and evaluation of foaming and emulsifying properties
Publication date: Available online 1 February 2020Source: Enzyme and Microbial TechnologyAuthor(s): Suping Ji, Chengsheng Jia, Dandan Cao, Shusheng Li, Xiaoming ZhangAbstractTrehalose diesters are Gemini-type surfactants that might have better surface activity than conventional surfactants. A one-step method for the preparation of trehalose unsaturated fatty acid diesters has been successfully developed. The yield of trehalose diester of different unsaturated fatty acids was between 78% and 88% under optimal conditions: 25 mmol/L trehalose, 100 mmol/L unsaturated fatty acid, 60 g/L 3 Å molecular sieves and 20 g/...
Source: Enzyme and Microbial Technology - February 2, 2020 Category: Biotechnology Source Type: research
Engineering of L-glutamate oxidase as the whole-cell biocatalyst for the improvement of α-ketoglutarate production
In this study, error-prone PCR mutagenesis of Streptomyces mobaraensis LGOX followed by high-throughput screening was performed to yield four single point mutants with improved enzymatic activity, termed F94L, S280T, I282M and H533R. Moreover, site-saturation mutagenesis at these four residues was employed, yielding two additionally improved mutants, termed I282L and H533L. Subsequently, we employed combinatorial mutagenesis of two, three and four point mutants, and the best mutant S280TH533L showed 90% higher enzymatic activity than the wild-type control. The data also showed that the presence of these point mutations gre...
Source: Enzyme and Microbial Technology - February 1, 2020 Category: Biotechnology Source Type: research
Preference for particular lanthanide species and thermal stability of XoxFs in Methylorubrum extorquens strain AM1
In this study, we found that (i) strain AM1 cells preferentially utilize La3+ rather than Nd3+ for growth, (ii) XoxF purified from cells grown with a La3+ and Nd3+ mixture contained a larger proportion of La3+, and (iii) La3+-metallated XoxF has higher activity and thermal stability than Nd3+-metallated XoxF, although (iv) both enzymes showed unchanged surface charges. Thermal shift assay in particular revealed that metallation affects the temperature for subunit denaturation but not for subunit dissociation. We concluded that, although La3+ and Nd3+ have similar distributions in nature, XoxF could chose La3+ preferentiall...
Source: Enzyme and Microbial Technology - February 1, 2020 Category: Biotechnology Source Type: research
The membrane-bound sorbosone dehydrogenase of Gluconacetobacter liquefaciens is a pyrroloquinoline quinone-dependent enzyme
Publication date: Available online 28 January 2020Source: Enzyme and Microbial TechnologyAuthor(s): Toshiharu Yakushi, Ryota Takahashi, Minenosuke Matsutani, Naoya Kataoka, Roque A. Hours, Yoshitaka Ano, Osao Adachi, Kazunobu MatsushitaAbstractMembrane-bound sorbosone dehydrogenase (SNDH) of Gluconacetobacter liquefaciens oxidizes L-sorbosone to 2-keto-L-gulonic acid (2KGLA), a key intermediate in vitamin C production. We constructed recombinant Escherichia coli and Gluconobacter strains harboring plasmids carrying the sndh gene from Ga. liquefaciens strain RCTMR10 to identify the prosthetic group of SNDH. The membranes of...
Source: Enzyme and Microbial Technology - January 29, 2020 Category: Biotechnology Source Type: research
CRISPR/Cas9 facilitates rapid generation of constitutive forms of transcription factors in Aspergillus niger through specific on-site genomic mutations resulting in increased saccharification of plant biomass
In this study, we show that CRISPR/Cas9 can also be used to efficiently change functional properties of the proteins encoded by the target gene by on-site genomic mutations in A. niger. The obtained strains with constitutively active XlnR and GaaR versions resulted in increased production of plant biomass degrading enzymes and improved release of D-xylose and L-arabinose from wheat bran, and D-galacturonic acid from sugar beet pulp. (Source: Enzyme and Microbial Technology)
Source: Enzyme and Microbial Technology - January 26, 2020 Category: Biotechnology Source Type: research
Semi-rational approach to Expand the Acyl-CoA Chain Length Tolerance of Sphingomonas paucimobilis Serine Palmitoyltransferase
Publication date: Available online 21 January 2020Source: Enzyme and Microbial TechnologyAuthor(s): Hyunjun Choe, Minsun Cha, Jon D. StewartAbstractSerine palmitoyltransferase (SPTase), the first enzyme of the sphingolipid biosynthesis pathway, produces 3-ketodihydrosphingosine by a Claisen-like condensation / decarboxylation reaction of L-Ser and palmitoyl-CoA (n-C16-CoA). Previous structural analysis of Sphingomonas paucimobilis SPTase (SpSPTase) revealed a dynamic active site loop (RPPATP; amino acids 378 - 383) in which R378 (underlined) forms a salt bridge with the carboxylic acid group of the PLP : L-Ser external ald...
Source: Enzyme and Microbial Technology - January 22, 2020 Category: Biotechnology Source Type: research
Enzymatic epoxidation of cyclohexene by peroxidase immobilization on a textile and an adapted reactor design
Publication date: Available online 20 January 2020Source: Enzyme and Microbial TechnologyAuthor(s): D.S. Wunschik, Kim N. Ingenbosch, P. Süss, U. Liebelt, S. Quint, M. Dyllick-Brenzinger, R. Zuhse, U. Menyes, K. Hoffmann-Jacobsen, K. Opwis, J.S. GutmannAbstractA textile-based reaction system for new peroxidase reactions in non-native media was implemented. The epoxidation of cyclohexene by the commercial peroxidase MaxiBright® was realized with the textile-immobilized enzyme in an adapted liquid-liquid two-phase reactor. A commercially available polyester felt was used as low-price carrier and functionalized with polyvin...
Source: Enzyme and Microbial Technology - January 21, 2020 Category: Biotechnology Source Type: research
