Abstract：
:Bacterial chitinases recruited multiple accessory domains for the conversion of recalcitrant polysaccharides to simple soluble sugars/amino sugars. Here, we report detailed properties of a multi-domain GH18 chitinase from Enterobacter cloacae subsp. cloacae (EcChi2) that preferred β-chitin as substrate. EcChi2 exhibited transglycosylation (TG) activity on oligomeric substrates from DP4-DP6. The high amount of DP2 is indicative of exo mode activity of EcChi2. We generated EcChi2 variants (truncated and fusion chimeras) and elucidated the role of catalytic and accessory domains. The catalytic efficiency of truncated GH18 and fusion chimera of GH18+ChBD1-ChBD2 decreased to 22 and 17-fold, respectively, than EcChi2, and lost the hydrolytic activity on polymeric substrates, except colloidal chitin. On the other hand, the catalytic activity of truncated PKD1-GH18-PKD2 on polymeric and oligomeric substrates was similar to EcChi2, suggesting that PKD domains are essential for increasing the rate of hydrolysis. Moreover, the truncated ChBD1-ChBD2 and fusion PKD1 + PKD2 participated in chitin-binding.
journal_name
Enzyme Microb Technoljournal_title
Enzyme and microbial technologyauthors
Mallakuntla MK,Podile ARdoi
10.1016/j.enzmictec.2020.109702subject
Has Abstractpub_date
2021-02-01 00:00:00pages
109702eissn
0141-0229issn
1879-0909pii
S0141-0229(20)30195-2journal_volume
143pub_type
杂志文章abstract：:Spodoptera frugiperda insect cells (IPLB-Sf21-AE) (Sf21), infected with baculovirus expression vectors during their exponential growth phase, are commonly used to produce a variety of heterologous recombinant proteins. In the present study the culture conditions of these insect cells were studied to establish high-den...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(94)90022-1
更新日期：1994-06-01 00:00:00
abstract：:Monod kinetic parameters provide information required for kinetic analysis of anaerobic oxidation of methane coupled to denitrification (AOM-D). This information is critical for engineering AOM-D processes in wastewater treatment facilities. We first experimentally determined Monod kinetic parameters for an AOM-D enri...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2017.05.005
更新日期：2017-09-01 00:00:00
abstract：:We have examined the chain length selectivity for a series of acyl donors by lipase B from Candida antarctica (CalB). CalB accepted aliphatic diesters of C4, C6 and C12 chain lengths equally. The introduction of a carbon-carbon double bond into the C4 esters dramatically lowered the rate constant associated with polym...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.03.006
更新日期：2014-05-10 00:00:00
abstract：:Turanose is a natural isomer of sucrose. It is an emerging functional sweetener of the next generation. Turanose is catalytically synthesized from the sucrose biomass by employing amylosucrase enzyme. In this study, a novel gene encoding amylosucrase (Asmet) has been identified from the metagenome of a thermal aquatic...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.109372
更新日期：2019-12-01 00:00:00
abstract：:Human interferon alpha 2b (IFN α2b) is a type I interferon exhibiting antiviral, anti-proliferative and immunomodulatory activities. The clinical outcome of the approved recombinant human IFN α2b drugs in the market suffers from short plasma half-life, rapid clearance and other side effects. Human IFN α2b expression i...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.05.007
更新日期：2019-09-01 00:00:00
abstract：:The effect of treatment with various intercalating dyes on the ability to produce antibiotics in Micromonospora rosaria and Micromonospora purpurea was studied. Treatment with acriflavine resulted in a high frequency loss of antibiotic productivity in both species. In M. rosaria, the loss of antibiotic-producing abili...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(90)90128-d
更新日期：1990-08-01 00:00:00
abstract：:We generated a bifunctional enzyme chimera containing the xylanase and lichenase coupled with SpyTag between them. Meanwhile, we generated another chimera containing SpyCatcher and elastin-like polypeptides (ELPs). As ELPs could bond to the xylanase-lichenase chimera through SpyTag/SpyCatcher spontaneous reaction in m...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2018.04.007
更新日期：2018-08-01 00:00:00
abstract：:The fatty acid methyl esters and fatty acid ethyl esters are known as biodiesels which are considered to be renewable, nontoxic and biodegradable biofuels. However, the conventional biodiesels show a high crystallization temperature which is one of the most critical obstacles against the widespread biodiesel usage. Th...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2017.03.012
更新日期：2017-07-01 00:00:00
abstract：:Two acidic β-glucosidases (βGI and βGII) from the brown rot fungus Fomitopsis palustris were purified to homogeneity by several chromatographic steps. βGI and βGII had molecular weights of 130 and 213 kDa, respectively, and exhibited optimum activity at pH 2.5 and 55°C. The K(m) values of βGI and βGII for p-nitropheny...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2010.12.012
更新日期：2011-04-07 00:00:00
abstract：:The novel termite gut metagenomic-derived GH11 xylanase gene xyl7 was expressed in Escherichia coli BL21, and the purified XYL7 enzyme exhibited high specific activity (6340U/mg) and broad pH active range of 5.5-10.0. Directed evolution was employed to enhance the thermostability of XYL7; two mutants (XYL7-TC and XYL7...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.11.005
更新日期：2015-03-01 00:00:00
abstract：:Kinetics of nitrification and denitrification of synthetic wastewater was investigated by using two reactors in series. An activated sludge unit was used for nitrification followed by a downflow biofilter for denitrification. Glucose solution was fed to the denitrification column to supply carbon source. Reactors were...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/s0141-0229(00)00145-9
更新日期：2000-07-01 00:00:00
abstract：:The effect of hexoses (glucose and galactose) addition to the feed xylose mineral medium of Debaryomyces hansenii chemostat cultures grown at a constant dilution rate of 0.055 h(-1) was studied. Xylitol was the major product detected amongst all tested conditions. The maximal values for xylitol yield and volumetric pr...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/s0141-0229(00)00166-6
更新日期：2000-06-01 00:00:00
abstract：:An intracellular alcohol oxidase (AOX) was isolated from the white-rot basidiomycete Phanerochaete chrysosporium (Pch), grown on l-lactate induction medium, and purified to electrophoretic homogeneity. The dimeric protein consisted of two identical 75kDa subunits. The open reading frame of 1,956bp resulted in a monome...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.04.001
更新日期：2014-07-01 00:00:00
abstract：:This work describes for the first time the green synthesis of neopentyl glycol diheptanoate in a solvent-free medium via an enzymatic pathway. The process has been carried out in an open-air reactor in order to ease water removal through evaporation and shift the chemical equilibrium towards product formation. The inh...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.109400
更新日期：2020-01-01 00:00:00
abstract：:Mycobacterium tuberculosis acetohydroxyacid synthase (M. tuberculosis AHAS) has been proposed to bean essential target for novel herbicide- and chemical-based antibacterial agents. Therefore, here we investigated the roles of multiple conserved herbicide-binding site residues (R318, A146, Q148, M512, and V513) in M. t...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2015.06.009
更新日期：2015-10-01 00:00:00
abstract：:Nitrification kinetics of synthetic saline wastewater was investigated by using an activated sludge unit. Initial experiments were performed with salt-free wastewater to obtain baseline information. Experiments with 3% salt concentration were performed at different sludge ages in order to investigate the system perfor...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/s0141-0229(01)00312-x
更新日期：2001-05-07 00:00:00
abstract：:Nine proteins with lignin peroxidase activity were separated from cultures of Phanerochaete chrysosporium INA-12 in glycerol as carbon source and non-nitrogen limited. Four lignin peroxidase isozymes (4, 5, 8, 9) were purified and characterized. Although differences in kinetic parameters could be shown, antibody react...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(90)90056-v
更新日期：1990-06-01 00:00:00
abstract：:In this work, a biosensor using a glassy carbon electrode modified with gold nanoparticles (AuNPs) and tyrosinase (Tyr) within a dihexadecylphosphate film is proposed. Cystamine and glutaraldehyde crosslinking agents were used as a support for Tyr immobilization. The proposed biosensor was characterized by scanning el...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2015.12.004
更新日期：2016-03-01 00:00:00
abstract：:Kinetic resolution of sec-alcohols is a green process with biocatalyst. Candida antarctica lipase B (CALB) displayed on Pichia pastoris cell-surface (Pp-CALB) was characterized in kinetic resolution of sec-alcohols with different structures. The reaction parameters including acyl donors, molar ratio of substrates, sol...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2017.11.005
更新日期：2018-03-01 00:00:00
abstract：:Advantages in maltose fermentation at extremely low temperatures (5-10°C) using an alcohol resistant and cryotolerant yeast strain (Saccharomyces cerevisiae AXAZ-1) immobilized on porous cellulosic material (or tubular cellulose, TC), produced by delignification of wood sawdust, are reported. Pure maltose and glucose ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.08.007
更新日期：2014-11-01 00:00:00
abstract：:The cell wall integrity and stress response component (WSC) domain was first described in the Wsc-family protein of the yeast Saccharomyces cerevisiae, and later found in diverse eukaryotic organisms. Due solely to their presence in the Wsc-family proteins working as a plasma membrane sensor for surface stress and in ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2019.02.009
更新日期：2019-06-01 00:00:00
abstract：:The selected thermotolerant, lactose-utilizing yeast strain Kluyveromyces marxianus NBIMCC 8362 possesses high specific d-amino acid oxidase activity (60Ug(-1)), which was increased nine-fold (545Ug(-1)) by design of the growth medium and conditions for d-amino oxidase induction. Applying an optimized simple and rapid...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2007.08.010
更新日期：2008-01-01 00:00:00
abstract：:The xylanase R8 gene (xynR8) from uncultured rumen fungi was cloned and successfully expressed in Lactobacillus reuteri. A xylanase activity of 132.1 U/mL was found in the broth of L. reuteri R8, the transformant containing pNZ3004 vector with xynR8 gene insertion. Two distinct forms of recombinant xylanase with diffe...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2014.06.004
更新日期：2014-10-01 00:00:00
abstract：:This study examines a novel method to reduce the probability of disulfide mismatches during the refolding process by the replacement of cysteines within a protein. Specifically, Cys383 of recombinant rat procarboxypeptidase B was replaced by other amino acids to increase the refolding efficiency in vitro. Mutants C383...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2011.04.018
更新日期：2011-07-10 00:00:00
abstract：:The methyl ester of 2-benzoxazolon-3-yl-acetic acid was used as an acyl donor in the penicillin amidase-catalysed transfer reaction to 7-aminodesacetoxycephalosporanic acid. The synthesis of 7-(2-benzoxazolon-3-yl-acetamido)-desacetoxycephalosporanic acid was carried out as a kinetically controlled reaction. A charact...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(92)90144-d
更新日期：1992-06-01 00:00:00
abstract：:Direct cellobiose production from cellulose by a genetically modified fungus-Neurospora crassa, was explored in this study. A library of N. crassa sextuple beta-glucosidase (bgl) gene deletion strains was constructed. Various concentrations of cellobiose were detected in the culture broth of the N. crassa sextuple bet...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2012.12.010
更新日期：2013-03-05 00:00:00
abstract：:The characterization of the S' subsite specificity of native and ethylated alpha-chymotrypsin has been studied via acyl transfer reaction in acetonitrile containing 10 vol% of water. Using Ac-Tyr-OEt as acyl donor, we investigated the partitioning of acyl-chymotrypsins between water and amino acid and peptide-derived ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(94)90125-2
更新日期：1994-07-01 00:00:00
abstract：:Different lipases have been immobilized on octyl agarose beads at 1mg/g and at maximum loading, via physical interfacial activation versus the octyl layer on the support. The stability of the preparations was analyzed. Most biocatalysts had the expected result: the apparent stability increased using the highly loaded ...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2016.12.002
更新日期：2017-03-01 00:00:00
abstract：:Gamma glutamyl transpeptidase from Bacillus pumilus KS12 (GGTBP) was cloned, expressed in pET-28-E. coli expression system as a heterodimeric enzyme with molecular weights of 45 and 20 kDa for large and small subunit, respectively. It was purified by nickel affinity chromatography with hydrolytic and transpeptidase ac...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/j.enzmictec.2011.08.005
更新日期：2012-03-10 00:00:00
abstract：:Recombinant plasmid pCED3 [confers beta-galactosidase production (LacZ+) and kanamycin resistance (Kmr)] in Bacillus subtilis was found to be both segregationally and structurally unstable. Since many solutions to segregational instability are already available, the problem of structural instability was specifically a...
journal_title：Enzyme and microbial technology
pub_type： 杂志文章
doi：10.1016/0141-0229(90)90160-r
更新日期：1990-05-01 00:00:00
