scholarly journals Isolation and Characterization of a Novel Cold-Active, Halotolerant Endoxylanase from Echinicola rosea Sp. Nov. JL3085T

Marine Drugs ◽  
2020 ◽  
Vol 18 (5) ◽  
pp. 245
Author(s):  
Jianlong He ◽  
Le Liu ◽  
Xiaoyan Liu ◽  
Kai Tang

We cloned a xylanase gene (xynT) from marine bacterium Echinicola rosea sp. nov. JL3085T and recombinantly expressed it in Escherichia coli BL21. This gene encoded a polypeptide with 379 amino acid residues and a molecular weight of ~43 kDa. Its amino acid sequence shared 45.3% similarity with an endoxylanase from Cellvibrio mixtus that belongs to glycoside hydrolases family 10 (GH10). The XynT showed maximum activity at 40 °C and pH 7.0, and a maximum velocity of 62 μmoL min−1 mg−1. The XynT retained its maximum activity by more than 69%, 51%, and 26% at 10 °C, 5 °C, and 0 °C, respectively. It also exhibited the highest activity of 135% in the presence of 4 M NaCl and retained 76% of its activity after 24 h incubation with 4 M NaCl. This novel xylanase, XynT, is a cold-active and halotolerant enzyme that may have promising applications in drug, food, feed, and bioremediation industries.

2004 ◽  
Vol 186 (15) ◽  
pp. 4885-4893 ◽  
Author(s):  
Takane Katayama ◽  
Akiko Sakuma ◽  
Takatoshi Kimura ◽  
Yutaka Makimura ◽  
Jun Hiratake ◽  
...  

ABSTRACT A genomic library of Bifidobacterium bifidum constructed in Escherichia coli was screened for the ability to hydrolyze the α-(1→2) linkage of 2′-fucosyllactose, and a gene encoding 1,2-α-l-fucosidase (AfcA) was isolated. The afcA gene was found to comprise 1,959 amino acid residues with a predicted molecular mass of 205 kDa and containing a signal peptide and a membrane anchor at the N and C termini, respectively. A domain responsible for fucosidase activity (the Fuc domain; amino acid residues 577 to 1474) was localized by deletion analysis and then purified as a hexahistidine-tagged protein. The recombinant Fuc domain specifically hydrolyzed the terminal α-(1→2)-fucosidic linkages of various oligosaccharides and a sugar chain of a glycoprotein. The stereochemical course of the hydrolysis of 2′-fucosyllactose was determined to be inversion by using 1H nuclear magnetic resonance. The primary structure of the Fuc domain exhibited no similarity to those of any glycoside hydrolases (GHs) but showed high similarity to those of several hypothetical proteins in a database. Thus, it was revealed that the AfcA protein constitutes a novel inverting GH family (GH family 95).


2006 ◽  
Vol 72 (9) ◽  
pp. 6399-6401 ◽  
Author(s):  
Jinhua Dong ◽  
Shinnosuke Hashikawa ◽  
Takafumi Konishi ◽  
Yutaka Tamaru ◽  
Toshiyoshi Araki

ABSTRACT The β-agarase C gene (agaC) of a marine bacterium, Vibrio sp. strain PO-303, consisted of 1,437 bp encoding 478 amino acid residues. β-Agarase C was identified as the first β-agarase that cannot hydrolyze neoagarooctaose and smaller neoagarooligosaccharides and was assigned to a novel glycoside hydrolase family.


Archaea ◽  
2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Vadim M. Gumerov ◽  
Andrey L. Rakitin ◽  
Andrey V. Mardanov ◽  
Nikolai V. Ravin

We expressed a putativeβ-galactosidase Asac_1390 from hyperthermophilic crenarchaeonAcidilobus saccharovoransinEscherichia coliand purified the recombinant enzyme. Asac_1390 is composed of 490 amino acid residues and showed high sequence similarity to family 1 glycoside hydrolases from various thermophilic Crenarchaeota. The maximum activity was observed at pH 6.0 and 93°C. The half-life of the enzyme at 90°C was about 7 hours. Asac_1390 displayed high tolerance to glucose and exhibits hydrolytic activity towards cellobiose and various aryl glucosides. The hydrolytic activity withp-nitrophenyl (pNP) substrates followed the order pNP-β-D-galactopyranoside (328 U mg−1), pNP-β-D-glucopyranoside (246 U mg−1), pNP-β-D-xylopyranoside (72 U mg−1), and pNP-β-D-mannopyranoside (28 U mg−1). Thus the enzyme was actually a multifunctionalβ-glycosidase. Therefore, the utilization of Asac_1390 may contribute to facilitating the efficient degradation of lignocellulosic biomass and help enhance bioconversion processes.


1977 ◽  
Vol 165 (3) ◽  
pp. 519-523 ◽  
Author(s):  
R J Naudé ◽  
W Oelofsen

1. Avian corticotropin (ACTH) was purified from both fresh and aged pituitary glands of the ostrich Struthio camelus. 2. The isolation of corticotropin in pure form involved acid/acetone extraction, NaCl fractionation, CM-cellulose chromatography and Sephadex G-50 chromatography. 3. The hormone preparations from fresh and aged glands behaved as single substances on polyacrylamide-gel electrophoresis, and both preparations were found to consist of 39 amino acid residues, in identical molar proportions for the different amino acids. 4. The isoelectric points of the two hormone preparations were estimated to be in the range pH 8.3-8.7, indicating possible differences in amide content, and the N-terminal amino acid of both preparations appeared to be serine. 5. The hormone preparations from fresh and aged glands exhibited similar biological potencies (73 and 77 i.u./mg respectively), as measured by steroidogenesis in vitro. 6. Apart from possible differences in amide content, the corticotropin preparations obtained from fresh and aged glands appear to be indistinguishable.


Marine Drugs ◽  
2019 ◽  
Vol 17 (10) ◽  
pp. 568 ◽  
Author(s):  
Jian Gao ◽  
Chunying Du ◽  
Yongzhou Chi ◽  
Siqi Zuo ◽  
Han Ye ◽  
...  

Ulvan lyases can degrade ulvan to oligosaccharides with potent biological activity. A new ulvan lyase gene, ALT3695, was identified in Alteromonas sp. A321. Soluble expression of ALT3695 was achieved in Escherichia coli BL21 (DE3). The 1314-bp gene encoded a protein with 437 amino acid residues. The amino acid sequence of ALT3695 exhibited low sequence identity with polysaccharide lyase family 25 (PL25) ulvan lyases from Pseudoalteromonas sp. PLSV (64.14% identity), Alteromonas sp. LOR (62.68% identity), and Nonlabens ulvanivorans PLR (57.37% identity). Recombinant ALT3695 was purified and the apparent molecular weight was about 53 kDa, which is different from that of other polysaccharide-degrading enzymes identified in Alteromonas sp. A321. ALT3695 exhibited maximal activity in 50 mM Tris-HCl buffer at pH 8.0 and 50 °C. ALT3695 was relatively thermostable, as 90% activity was observed after incubation at 40 °C for 3 h. The Km and Vmax values of ALT3695 towards ulvan were 0.43 mg·mL−1 and 0.11 μmol·min−1·mL−1, respectively. ESI-MS analysis showed that enzymatic products were mainly disaccharides and tetrasaccharides. This study reports a new PL25 family ulvan lyase, ALT3695, with properties that suggest its great potential for the preparation of ulvan oligosaccharides.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Quanfu Wang ◽  
Yanhua Hou ◽  
Yonglei Shi ◽  
Xiao Han ◽  
Qian Chen ◽  
...  

Glutaredoxins (Grxs) are small ubiquitous redox enzymes that catalyze glutathione-dependent reactions to reduce protein disulfide. In this study, a full-length Grx gene (PsGrx) with 270 nucleotides was isolated from Antarctic sea-ice bacteriumPseudoalteromonassp. AN178. It encoded deduced 89 amino acid residues with the molecular weight 9.8 kDa. Sequence analysis of the amino acid sequence revealed the catalytic motif CPYC. RecombinantPsGrx (rPsGrx) stably expressed inE. coliBL21 was purified to apparent homogeneity by Ni-affinity chromatography. rPsGrx exhibited optimal activity at 30°C and pH 8.0 and showed 25.5% of the activity at 0°C. It retained 65.0% of activity after incubation at 40°C for 20 min and still exhibited 37.0% activity in 1.0 M NaCl. These results indicated that rPsGrx was a typical cold active protein with low thermostability.


1993 ◽  
Vol 296 (1) ◽  
pp. 41-47 ◽  
Author(s):  
B G Kim ◽  
C L Brooks

Quantitative isolation of bovine prolactin was accomplished by immunoaffinity chromatography using clonal antibody as the stationary ligand. The phosphorylated and non-phosphorylated (native) prolactins contained in the immunopurified preparations were separated by chromatofocusing. Isolates from individual pituitaries revealed that phosphorylated prolactin represented between 20 and 80% of the total prolactin. The stoichiometry of phosphate in phosphorylated prolactin was 1.4:1 when determined by amino acid analysis after preparation of the S-ethylcysteine derivative. One major phosphorylation site, serine-90, and two minor sites, serine-26 and -34, were determined by mapping and sequencing studies. Serine-90 was conserved in prolactins, growth hormones and placental lactogens. Serine-26 and -34 were conserved in prolactins, but were not found in growth hormones or placental lactogens. Absorption spectroscopy of the aromatic amino acid residues indicated that phosphorylation of prolactin was associated with a unique structural conformation.


1995 ◽  
Vol 307 (2) ◽  
pp. 471-479 ◽  
Author(s):  
K Wang ◽  
L Gan ◽  
I Lee ◽  
L Hood

Based on genomic Southern hybridizations and cDNA sequence analyses, the chicken trypsinogen gene family can be divided into two multi-member subfamilies, a six-member trypsinogen I subfamily which encodes the cationic trypsin isoenzymes and a three-member trypsinogen II subfamily which encodes the anionic trypsin isoenzymes. The chicken cDNA and genomic clones containing these two subfamilies were isolated and characterized by DNA sequence analysis. The results indicated that the chicken trypsinogen genes encoded a signal peptide of 15 to 16 amino acid residues, an activation peptide of 9 to 10 residues and a trypsin of 223 amino acid residues. The chicken trypsinogens contain all the common catalytic and structural features for trypsins, including the catalytic triad His, Asp and Ser and the six disulphide bonds. The trypsinogen I and II subfamilies share approximately 70% sequence identity at the nucleotide and amino acid level. The sequence comparison among chicken trypsinogen subfamily members and trypsin sequences from other species suggested that the chicken trypsinogen genes may have evolved in coincidental or concerted fashion.


2005 ◽  
Vol 187 (12) ◽  
pp. 4286-4289 ◽  
Author(s):  
Longkuan Xiang ◽  
Bradley S. Moore

ABSTRACT The committed biosynthetic reaction to benzoyl-coenzyme A in the marine bacterium “Streptomyces maritimus” is carried out by the novel prokaryotic phenylalanine ammonia lyase (PAL) EncP, which converts the primary amino acid l-phenylalanine to trans-cinnamic acid. Recombinant EncP is specific for l-phenylalanine and shares many biochemical features with eukaryotic PALs, which are substantially larger proteins by ∼200 amino acid residues.


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