scholarly journals Identification and Characterization of a Novel Lectin from the Clam Glycymeris yessoensis and Its Functional Characterization under Microbial Stimulation and Environmental Stress

Marine Drugs ◽  
2021 ◽  
Vol 19 (9) ◽  
pp. 474
Author(s):  
Tatyana O. Mizgina ◽  
Irina V. Chikalovets ◽  
Valentina I. Molchanova ◽  
Rustam H. Ziganshin ◽  
Oleg V. Chernikov

Lectin from the bivalve Glycymeris yessoensis (GYL) was purified by affinity chromatography on porcine stomach mucin–Sepharose. GYL is a dimeric protein with a molecular mass of 36 kDa, as established by SDS-PAGE and MALDI-TOF analysis, consisting of 18 kDa subunits linked by a disulfide bridge. According to circular dichroism data, GYL is a β/α-protein with the predominance of β-structure. GYL preferentially agglutinates enzyme-treated rabbit erythrocytes and recognizes glycoproteins containing O-glycosidically linked glycans, such as porcine stomach mucin (PSM), fetuin, thyroglobulin, and ovalbumin. The amino acid sequences of five segments of GYL were acquired via mass spectrometry. The sequences have no homology with other known lectins. GYL is Ca2+-dependent and stable over a range above a pH of 8 and temperatures up to 20 °C for 30 min. GYL is a pattern recognition receptor, as it binds common pathogen-associated molecular patterns, such as peptidoglycan, LPS, β-1,3-glucan and mannan. GYL possesses a broad microbial-binding spectrum, including Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli, Vibrio proteolyticus), but not the fungus Candida albicans. Expression levels of GYL in the hemolymph were significantly upregulated after bacterial challenge by V. proteolyticus plus environmental stress (diesel fuel). Results indicate that GYL is probably a new member of the C-type lectin family, and may be involved in the immune response of G. yessoensis to bacterial attack.

2020 ◽  
Vol 17 (4) ◽  
pp. 729-737
Author(s):  
Le Dinh Hung ◽  
Dinh Thanh Trung

A lectin from the marine sponge Stylissa flexibilis, designated as SFL, was purified by cold ethanol precipitation followed by ion exchange chromatography on DEAE Sepharose column and Sephacryl S-200 gel filtration. SFL is a dimeric glycoprotein of 32 kDa subunits linked by a disulfide bridge with a molecular mass of 64 kDa by SDS-PAGE and 65 kDa by Sephacryl S-200 gel filtration chromatography. The lectin preferentially agglutinated enzyme treated human A erythrocytes, whereas it did not agglutinate any type of rabbit, human B and O erythrocytes, irrespective of treatment with enzymes. The hemagglutination activity of lectin was strongly inhibited by monosaccharide, D-galactose and glycoproteins, asialo-porcine stomach mucin and asialo-fetuin, indicating that lectin is specific for O-glycans. Activity of SFL was stable over a range of pH from 5 to 8, up to 60 °C for 30 min and its activity was Ca2+ dependent, indicating that SFL was belonged to the C-type lectin family and requires metal for biological activity. SFL caused agglutination of Vibrio alginolyticus and V. parahaemolyticus in a dose dependent manner and inhibited the growth rate of these bacterial strains, suggesting that the lectin caused the agglutination through binding to the target receptor(s) on the surface of Vibrios. Thus, SFL can be considered as a good source of lectin(s) being useful as carbohydrate probe and antibacterial reagent.


1998 ◽  
Vol 63 (3) ◽  
pp. 434-440 ◽  
Author(s):  
Irena Hulová ◽  
Jana Barthová ◽  
Helena Ryšlavá ◽  
Václav Kašička

Glycoproteins that have affinity to Concanavalin A were isolated from the acetone-dried pituitaries of common carp (Cyprinus carpio L.). Two fractions of glycoproteins were separated using gel chromatography on Superdex 75HR. The fraction with lower molecular weight (30 000) corresponding to the carp gonadotropin cGtH II was composed of two subunits as determined using SDS-PAGE. This protein fraction was further divided into four components using reversed-phase HPLC. Two fractions were pure α and β subunits of cGtH II as follows from immunodetection and from determination of N-terminal amino acid sequences. The other two were a mixture of α and β subunits as was also revealed by N-terminal analysis. Capillary electrophoresis was also used for characterization of isolated glycoproteins.


1995 ◽  
Vol 42 (3) ◽  
pp. 351-356 ◽  
Author(s):  
M Warwas ◽  
J Gburek ◽  
J Osada ◽  
K Gołab

It is the second peptidase inhibitor, after ovostatin, which showing the same antipapain activity in egg white in different avian species implies differences in amino-acid sequences. Cystatin from duck egg white was purified by carboxymethylpapain affinity chromatography and size-exclusion HPLC. The purified inhibitor which showed partial identity in the immunodiffusion test with chicken egg white cystatin, had an apparent molecular mass of 9.3 kDa as determined by SDS/PAGE. IEF analysis revealed five molecular forms of pI in the range 7.8-8.4. The obtained cystatin was neither glycosylated nor phosphorylated as it is in the case of chicken cystatin. The determined Ki (0.005 +/- 0.001 nM) was similar to that reported for human and chicken cystatin C.


2000 ◽  
Vol 278 (5) ◽  
pp. F784-F791 ◽  
Author(s):  
Olugbenga A. Adebanjo ◽  
Gopa Biswas ◽  
Baljit S. Moonga ◽  
Hindupur K. Anandatheerthavarada ◽  
Li Sun ◽  
...  

We report the first biochemical and functional characterization of inositol trisphosphate receptors (IP3Rs) and ryanodine receptors (RyRs) in the nuclear membrane of bone-forming (MC3T3-E1) osteoblasts. Intact nuclei fluoresced intensely with anti-RyR (Ab34) and anti-IP3R (Ab40) antisera in a typically peripheral nuclear membrane pattern. Isolated nuclear membranes were next subjected to SDS-PAGE and blotted with isoform-specific anti-receptor antisera, notably Ab40, anti-RyR-1, anti-RyR-2 (Ab129), and anti-RyR-3 (Ab180). Only anti-RyR-1 and Ab40 showed bands corresponding, respectively, to full-length RyR-1 (∼500 kDa) and IP3R-1 (∼250 kDa). Band intensity was reduced by just ∼20% after brief tryptic proteolysis of intact nuclei; this confirmed that isolated nuclear membranes were mostly free of endoplasmic reticular contaminants. Finally, the nucleoplasmic Ca2+ concentration ([Ca2+]np) was measured in single nuclei by using fura-dextran. The nuclear envelope was initially loaded with Ca2+ via Ca2+-ATPase activation (1 mM ATP and ∼100 nM Ca2+). Adequate Ca2+ loading was next confirmed by imaging the nuclear envelope (and nucleoplasm). Exposure of Ca2+-loaded nuclei to IP3 or cADP ribose resulted in a rapid and sustained [Ca2+]np elevation. Taken together, the results provide complementary evidence for nucleoplasmic Ca2+ influx in osteoblasts through nuclear membrane-resident IP3Rs and RyRs. Our findings may conceivably explain the direct regulation of osteoblastic gene expression by hormones that use the IP3-Ca2+pathway.


2008 ◽  
Vol 190 (19) ◽  
pp. 6318-6329 ◽  
Author(s):  
Maria Billini ◽  
Kostas Stamatakis ◽  
Vicky Sophianopoulou

ABSTRACT Synechococcus elongatus strain PCC 7942 is an alkaliphilic cyanobacterium that tolerates a relatively high salt concentration as a freshwater microorganism. Its genome sequence revealed seven genes, nha1 to nha7 (syn_pcc79420811, syn_pcc79421264, syn_pcc7942359, syn_pcc79420546, syn_pcc79420307, syn_pcc79422394, and syn_pcc79422186), and the deduced amino acid sequences encoded by these genes are similar to those of Na+/H+ antiporters. The present work focused on molecular and functional characterization of these nha genes encoding Na+/H+ antiporters. Our results show that of the nha genes expressed in Escherichia coli, only nha3 complemented the deficient Na+/H+ antiporter activity of the Na+-sensitive TO114 recipient strain. Moreover, two of the cyanobacterial strains with separate disruptions in the nha genes (Δnha1, Δnha2, Δnha3, Δnha4, Δnha5, and Δnha7) had a phenotype different from that of the wild type. In particular, ΔnhA3 cells showed a high-salt- and alkaline-pH-sensitive phenotype, while Δnha2 cells showed low salt and alkaline pH sensitivity. Finally, the transcriptional profile of the nha1 to nha7 genes, monitored using the real-time PCR technique, revealed that the nha6 gene is upregulated and the nha1 gene is downregulated under certain environmental conditions.


Peptides ◽  
2004 ◽  
Vol 25 (2) ◽  
pp. 143-150 ◽  
Author(s):  
Xian-Chun Zeng ◽  
San-Xia Wang ◽  
Yan Zhu ◽  
Shun-Yi Zhu ◽  
Wen-Xin Li

2007 ◽  
Vol 189 (15) ◽  
pp. 5515-5522 ◽  
Author(s):  
Yuji Miyamoto ◽  
Tetsu Mukai ◽  
Yumi Maeda ◽  
Noboru Nakata ◽  
Masanori Kai ◽  
...  

ABSTRACT The cell envelopes of several species of nontuberculous mycobacteria, including the Mycobacterium avium complex, contain glycopeptidolipids (GPLs) as major glycolipid components. GPLs are highly antigenic surface molecules, and their variant oligosaccharides define each serotype of the M. avium complex. In the oligosaccharide portion of GPLs, the fucose residue is one of the major sugar moieties, but its biosynthesis remains unclear. To elucidate it, we focused on the 5.0-kb chromosomal region of the M. avium complex that includes five genes, two of which showed high levels of similarity to the genes involved in fucose synthesis. For the characterization of this region by deletion and expression analyses, we constructed a recombinant Mycobacterium smegmatis strain that possesses the rtfA gene of the M. avium complex to produce serovar 1 GPL. The results revealed that the 5.0-kb chromosomal region is responsible for the addition of the fucose residue to serovar 1 GPL and that the three genes mdhtA, merA, and gtfD are indispensable for the fucosylation. Functional characterization revealed that the gtfD gene encodes a glycosyltransferase that transfers a fucose residue via 1→3 linkage to a rhamnose residue of serovar 1 GPL. The other two genes, mdhtA and merA, contributed to the formation of the fucose residue and were predicted to encode the enzymes responsible for the synthesis of fucose from mannose based on their deduced amino acid sequences. These results indicate that the fucosylation pathway in GPL biosynthesis is controlled by a combination of the mdhtA, merA, and gtfD genes. Our findings may contribute to the clarification of the complex glycosylation pathways involved in forming the oligosaccharide portion of GPLs from the M. avium complex, which are structurally distinct.


2013 ◽  
Vol 8 (12) ◽  
pp. 1183-1193 ◽  
Author(s):  
Marcin Maciąga ◽  
Michał Szkop ◽  
Andrzej Paszkowski

AbstractSix allozymes of aspartate aminotransferase (AAT, EC 2.6.1.1): three plastidial (AAT-2 zone) and three cytosolic (AAT-3 zone) were isolated from common wheat (Triticum aestivum) seedlings and highly purified by a five-step purification procedure. The identity of the studied proteins was confirmed by mass spectrometry. The molecular weight of AAT allozymes determined by gel filtration was 72.4±3.6 kDa. The molecular weights of plastidial and cytosolic allozymes estimated by SDS-PAGE were 45.3 and 43.7 kDa, respectively. The apparent Michaelis constant (K m) values determined for four substrates appeared to be very similar for each allozyme. The values of the turnover number (k cat) and the k cat/K m ratio calculated for allozymes with L-aspartate as a leading substrate were in the range of 88.5–103.8 s−1/10,412–10,795 s−1 M−1 for AAT-2 zone and 4.6–7.0 s−1/527–700 s−1 M−1 for AAT-3 zone. These results clearly demonstrated much higher catalytic efficiency of AAT-2 allozymes. Therefore, partial sequences of cDNA encoding AATs from different zones were obtained using the RT-PCR technique. Comparison of the AAT-2 and AAT-3 amino acid sequences from active site regions revealed five non-conservative substitutions, which impact on the observed differences in the isozymes catalytic efficiency is discussed.


2004 ◽  
Vol 186 (2) ◽  
pp. 411-418 ◽  
Author(s):  
Hong-Suk Kim ◽  
Hyoung-Joon Park ◽  
Sunggi Heu ◽  
Jin Jung

ABSTRACT A novel sucrose hydrolase (SUH) from Xanthomonas axonopodis pv. glycines, a causative agent of bacterial pustule disease on soybeans, was studied at the functional and molecular levels. SUH was shown to act rather specifically on sucrose (Km = 2.5 mM) but not on sucrose-6-phosphate. Protein analysis of purified SUH revealed that, in this monomeric enzyme with an estimated molecular mass of 70,223 ± 12 Da, amino acid sequences determined for several segments have corresponding nucleotide sequences in XAC3490, a protein-coding gene found in the genome of X. axonopodis pv. citri. Based on this information, the SUH gene, consisting of an open reading frame of 1,935 bp, was cloned by screening a genomic library of X. axonopodis pv. glycines 8ra. Database searches and sequence comparison revealed that SUH has significant homology to some family 13 enzymes, with all of the crucial invariant residues involved in the catalytic mechanism conserved, but it shows no similarity to known invertases belonging to family 32. suh expression in X. axonopodis pv. glycines requires sucrose induction, and insertional mutagenesis resulted in an absence of sucrose-inducible sucrose hydrolase activity in crude protein extracts and a sucrose-negative phenotype. Recombinant SUH, overproduced in Escherichia coli and purified, was shown to have the same enzymatic characteristics in terms of kinetic parameters.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4242
Author(s):  
Qian Lin ◽  
Qingqing Fu ◽  
Daiwen Chen ◽  
Bing Yu ◽  
Yuheng Luo ◽  
...  

Porcine NK-Lysine (PNKL) is a new antimicrobial peptide (AMP) identified in the small intestine. In this study, PNKL protein was obtained through heterologous expression in Escherichia coli and was estimated by SDS-PAGE at 33 kDa. The antibacterial activities of PNKL were determined using various bacterial strains and showed broad-spectrum antimicrobial activity against Gram-negative and Gram-positive bacteria. Furthermore, E. coli K88-challenged IPEC-J2 cells were used to determine PNKL influences on inflammatory responses. Hemolytic assays showed that PNKL had no detrimental impact on cell viability. Interestingly, PNKL elevated the viability of IPEC-J2 cells exposure to E. coli K88. PNKL significantly decreased the cell apoptosis rate, and improved the distribution and abundance of tight junction protein ZO-1 in IPEC-J2 cells upon E. coli K88-challenge. Importantly, PNKL not only down regulated the expressions of inflammatory cytokines such as the IL-6 and TNF-α, but also down regulated the expressions of NF-κB, Caspase3, and Caspase9 in the E. coli K88-challenged cells. These results suggest a novel function of natural killer (NK)-lysin, and the anti-bacterial and anti-inflammatory properties of PNKL may allow it a potential substitute for conventionally used antibiotics or drugs.


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