Abstract：
:Chitooligosaccharides (COS) are hydrolytic products of chitosan that are essential in functional food, medicine, and other fields due to their biological activities. Commercial COS are often prepared by the hydrolysis of chitosan by chitosanase. In this study, a glycoside hydrolase family 46 cluster B chitosanase from Bacillus amyloliquefaciens (BaCsn46B) was efficiently expressed in Pichia pastoris. The recombinant enzyme was secreted into the culture medium that reached a total extracellular protein concentration of 4.5 g/L with an activity of 8907.2 U/mL in a high cell density fermenter (5 L). The molecular mass of deglycosylated BaCsn46B was 29.0 kDa. Purified BaCsn46B exhibited excellent enzymatic properties, which had high specific activity (2380.5 U/mg) under optimal reaction conditions (55 °C and pH 6.5). BaCsn46B hydrolyzed chitosan yielded a series of COS with different degrees of polymerization by endo-type cleavage. The end hydrolytic products of BaCsn46B were chitobiose and chitotriose, while no monosaccharide yield was evident in the hydrolytic reaction. The excellent secreted expression level and hydrolytic performance make the enzyme a desirable biocatalyst for the industrial preparation of COS.
journal_name
Int J Biol Macromoljournal_title
International journal of biological macromoleculesauthors
Luo S,Qin Z,Chen Q,Fan L,Jiang L,Zhao Ldoi
10.1016/j.ijbiomac.2020.02.001subject
Has Abstractpub_date
2020-04-15 00:00:00pages
1034-1041eissn
0141-8130issn
1879-0003pii
S0141-8130(19)40470-4journal_volume
149pub_type
杂志文章abstract：:The thermal stability and enzymatic activity of bovine pancreatic ribonuclease A (RNase A) have been investigated in the presence of a homologous series of cationic gemini surfactants (alkanediyl-α,ω-bis(hydroxyethyl methyl hexadecyl ammonium bromide)). UV, circular dichorism and fluorescence spectroscopies have been ...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2012.01.027
更新日期：2012-05-01 00:00:00
abstract：:The immuno-modulating activities and chemical characteristics of exo-biopolymer (EX-GF) produced by a submerged mycelial culture of Grifola frondosa were studied. The EX-GF was fractionated into EX-GF-Fr.I, II, and III by Sephadex G-100 gel chromatography. Anti-complementary activity of EX-GF-Fr.III was highest (71.1%...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2007.02.012
更新日期：2007-08-01 00:00:00
abstract：:A thermostable superoxide dismutase from thermophilic bacterium Anoxybacillus gonensis KA 55 MTCC 12684 which was isolated from Manikaran hotspring of Himachal Pradesh was purified to apparent homogeneity by fractional ammonium sulphate precipitation and anion exchange chromatography. A purification factor of 33.1-fol...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2018.06.031
更新日期：2018-10-01 00:00:00
abstract：:Staphylopine is a newly identified broad-spectrum metallophore for metal acquisition, and it plays important roles in the survival and virulence of Staphylococcus aureus and other pathogens in the metal-scarce environment in hosts. CntK catalyzes the first step of staphylopine synthesis by converting L-histidine to D-...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2019.05.169
更新日期：2019-08-15 00:00:00
abstract：:Porous scaffolds composed of alginate (AG) and chitosan (CS) were fabricated by combining the formation of polyelectrolyte complex (PEC) with freeze-drying. The AG scaffold was used as a framework with uniformly distributed and interconnected pore structure. The chitosan or chitosan/hydroxyapatite (CS/HA) composite so...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2009.11.004
更新日期：2010-03-01 00:00:00
abstract：:Polymer degradation through lipase appears to be an enthralling alternative to bulk chemical routes. Poly (ε-caprolactone) (PCL) is an artificial polyester that can be degraded by microbes and enzymes like lipases and esterases. The environmental degradation of PCL is dependent on the activity of bacteria that charact...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2016.11.040
更新日期：2017-02-01 00:00:00
abstract：:Biodegradable flocculants of Gum ghatti (Gg) with acrylamide (AAm) were prepared through graft co-polymerization technique using potassium persulphate (KPS)-ascorbic acid (ABC) redox pair as initiator and N,N'-methylene-bis-acrylamide (MBA) as a crosslinker. Gg-cl-poly(AAm) was found to exhibit pH and temperature resp...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2013.03.045
更新日期：2013-07-01 00:00:00
abstract：:Oxidized sucrose cross-linked Schizophyllan nanogel was successfully synthesized via inverse emulsion method for the first time. The synthesis process was conducted in the absence of both toxic cross-linker and organic solvent. The nanogel crosslinking network was prepared using fractionated coconut oil as the continu...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2018.08.119
更新日期：2018-12-01 00:00:00
abstract：:In this study, the complex coacervation of whey protein isolate (WPI) and quince seed mucilage (QSM) was studied as a function of pH (7.0-2.0), biopolymers concentration (0.05, 0.1 and 0.5%) and WPI:QSM ratio (10:90 to 90:10), according to protolytic titration, electrical conductivity (EC) and turbidity analyses. The ...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2019.03.026
更新日期：2019-06-15 00:00:00
abstract：:The corynemycolyltransferase proteins were identified from Corynebacterium glutamicum and Corynebacterium efficiens genomes using computational tools available in the public domain. Three-dimensional models were constructed for corynemycolyltransferases based on the crystal structures of related mycolyltransferases in...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2004.03.008
更新日期：2004-06-01 00:00:00
abstract：:We report the preparation of both control chitosan and magnetic chitosan beads as biosorbents using chitosan as matrix and magnetite (Fe3O4) nanoparticles as reinforcement followed by detailed advanced characterization. The batch trials were performed to study the adsorption kinetics of biosorbents by removing As(III)...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2020.06.287
更新日期：2020-11-15 00:00:00
abstract：:Recombinant hybrid Manganese superoxide dismutase from Staphyloccus saphropyticus/S. equorum (rMnSODSeq) exhibits stability at high temperatures. The enzyme occurs as a dimer that dissociates around 52°C prior to unfolding of the monomer around 64°C, demonstrating contribution of the dimeric form to stability. Here, s...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2017.01.096
更新日期：2017-05-01 00:00:00
abstract：:Bacterially synthesized poly(hydroxyalkanoate)s (PHAs) suffers from low crystallization rate which is enhanced by using tailor-made oxalamide compounds as nucleators. The influence of nucleator configurations on the crystallization behaviour of the PHAs was investigated using differential scanning calorimetry (DSC), p...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2017.06.001
更新日期：2017-11-01 00:00:00
abstract：:While polyethersulfone (PES) membrane represents a promising option for blood purification, the blood compatibility must be dramatically enhanced to meet today's ever-increasing demands for many emerging application. In this study, we report a bionic design for optimization and development of a modified PES membrane c...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2014.03.034
更新日期：2014-06-01 00:00:00
abstract：:The 129-residue lysozyme has been shown to form amyloid fibrils in vitro. While methylene blue (MB), a compound in the phenothiazinium family, has been shown to dissemble tau fibril formation, its anti-fibrillogenic effect has not been thoroughly characterized in other proteins/peptides. This study examines the effect...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2018.08.038
更新日期：2018-11-01 00:00:00
abstract：:The present study investigates the hypolipidemic effects of sulphated polysaccharide obtained from Codium fragile (CFSP) in induced obese rats (HFD). The results showed an increase in body weight of HFD rats by 21.56% as compared to control normal rats. Moreover, serum lipase activity underwent an increase which led t...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2017.04.017
更新日期：2017-09-01 00:00:00
abstract：:The synthesis and characterization of a novel biodegradable graft copolymer based on partially hydrolyzed polymethylacrylate (PMA) grafted amylopectin (AP) was reported which was developed for the synthesis of silver nanoparticles from silver nitrate solution by facile green technique. The prepared graft copolymer was...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2015.07.046
更新日期：2015-11-01 00:00:00
abstract：:Two COS mixtures and a low molecular weight chitosan (LMWC) were tested for potential cytotoxicity and genotoxicity upon human lymphocytes. Genotoxicity was evaluated in vitro by cytokinesis-blocked micronucleus and alkaline comet assays, while cytotoxicity was assessed by flow cytometry analysis. Our results suggest ...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2011.05.032
更新日期：2011-10-01 00:00:00
abstract：:Arginine kinase (AK), a crucial enzyme in energy metabolism, buffers cellular ATP levels by catalyzing the reversible phosphoryl transfer between ATP and arginine. To better understand the role of Cys271 in conformational changes of AK from greasyback shrimp (Metapenaeus ensis), we replaced the residue with serine and...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2011.04.002
更新日期：2011-07-01 00:00:00
abstract：:Using high pressure microfluidization, we prepared micro-fibrillated soybean cellulose (MFSC) and analyzed its morphology and structure. MFSC was then incorporated into low-methoxyl pectin (PC) to coat lactic acid bacteria (LAB) by ionotropic gelation, and the effects of PC-MFSC microgel on LAB survival in a simulated...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2020.04.161
更新日期：2020-05-06 00:00:00
abstract：:A water-soluble polysaccharide (BP-1) was obtained from highland barley (Hordeum vulgare L.) by hot water extraction and purification of sepharose column chromatography. BP-1 had an average molecular weight of about 6.7×104Da and was composed of glucose (Glc), xylose (Xyl), arabinose (Ara) and rhamnose (Rha) with a re...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2016.06.099
更新日期：2016-11-01 00:00:00
abstract：:Keeping in view the importance of polysaccharide gum in the pharmaceutical formulations, in the present work, exploration of the potential of the moringa gum in hydrogel formation for drug delivery applications has been carried out. The gum based hydrogels were prepared via radiation induced graft-copolymerization of ...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2018.09.148
更新日期：2018-12-01 00:00:00
abstract：:In this study, glucose oxidase and polyphenol oxidase were immobilized in conducting polymer matrices; polypyrrole and poly(N-(4-(3-thienyl methylene)-oxycarbonyl phenyl) maleimide-co-pyrrole) via electrochemical method. Fourier transform infrared and scanning electron microscope were employed to characterize the copo...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2006.12.005
更新日期：2007-06-01 00:00:00
abstract：:The biosynthesis of medium chain length poly(3-hydroxyalkanoates) mcl PHAs by Pseudomonas guezennei using glucose, sodium octanoate, and 10-undecenoic acid as sole or mixed carbon sources was investigated. Chemical composition of polyesters was analyzed by GCMS and NMR. The copolyester produced by P. guezennei from gl...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2012.08.018
更新日期：2012-12-01 00:00:00
abstract：:The structural modification of polysaccharides directly affects their physicochemical properties and applications. Dextran, a chained polysaccharide, consists of multiple d-glucose molecules with repetitive structures. In this study, the physicochemical properties of oxidized dextran (DO) at different concentrations o...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2019.12.104
更新日期：2020-02-01 00:00:00
abstract：:Galactomannan extracted from Trigonella persica endosperm like to other galactomannans is useful in the medicine and pharmaceutical industry such as drug delivery due to its unique physicochemical properties. As soon as germination takes place, the hydrolysis of galactomannan begins and its structure changes. Evaluati...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2019.06.225
更新日期：2019-09-15 00:00:00
abstract：:Effects of sodium dodecyl sulfate, dodecyltrimethylammonium bromide, sodium chloride, sodium sulfate, methanol and ethanol, on the structure and activity of adenosine deaminase (ADA) were investigated by UV-Vis, circular dichroism spectrophotometry and molecular dynamics (MDs) studies. Relative activity, experimental ...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2008.04.007
更新日期：2008-08-15 00:00:00
abstract：:Chara is a genus of freshwater alga that is evolutionarily observed at the aquatic-terrestrial boundary, whose cellulose microfibrils are similar to those of terrestrial plants regarding the crystallinity and biosynthesis of cellulose. Oven-dried and never-dried celluloses samples were prepared from chara. Terrestrial...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2017.12.051
更新日期：2018-04-01 00:00:00
abstract：:Bacterial vaginosis (BV) is a common type of vaginal inflammation caused by a proliferation of pathogenic bacteria, among which Mobiluncus curtisii. In our previous studies on M. curtisii genome, we identified the presence of a genomic fragment encoding a 25 kDa pore-forming toxin, the CAMP factor, which is known to b...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2019.10.107
更新日期：2020-05-01 00:00:00
abstract：:The present investigation reports an in-vitro study using combination of laccase and an enhancer capable of inhibiting the growth of pathogenic microorganisms, preventing biofilm formation, and whitening teeth. Laccase-cinnamic acid system remarkably inhibited the growth of Aggregatibacter actinomycetemcomitans, Candi...
journal_title：International journal of biological macromolecules
pub_type： 杂志文章
doi：10.1016/j.ijbiomac.2021.01.068
更新日期：2021-01-15 00:00:00
