Many patients with cholera emerge in Kolkata, India throughout the year. Such emergency indicates that cholera toxin-producing Vibrio cholerae O1 (toxigenic V. cholerae O1) are widespread in Kolkata.
View Article and Find Full Text PDFWe examined the stools of 23 patients in Kolkata, who were diagnosed as cholera patients because Vibrio cholerae O1 was detected from their stools by culturing methods, and further explored by metagenomic sequencing analysis. Subsequently, the presence of the gene encoding A subunit of cholera toxin (ctxA) and the cholera toxin (CT) level in these stool samples were examined. ctxA was examined by both metagenomic sequencing analysis and polymerase chain reaction.
View Article and Find Full Text PDFis a Gram-negative pathogen that causes food-borne illness. In immunocompromised patients and the elderly, opportunistically leads to severe extraintestinal diseases including sepsis, peritonitis, and meningitis. If that infects the intestinal tract causes such an extraintestinal infection, the pathogen must pass through the intestinal epithelial barrier.
View Article and Find Full Text PDFCholera toxin (CT)-producing O1 and O139 cause acute diarrheal disease and are proven etiological agents of cholera epidemics and pandemics. On the other hand, non-O1/non-O139 are designated as non-agglutinable (NAG) vibrios and are not associated with epidemic cholera. The majority of NAG vibrios do not possess the gene for CT ().
View Article and Find Full Text PDFspp. are Gram-negative rod-shaped bacteria ubiquitously distributed in diverse water sources. Several spp.
View Article and Find Full Text PDFserogroup O1 is responsible for epidemic and pandemic cholera and remains a global public health threat. This organism has been well established as a resident flora of the aquatic environment that alters its phenotypic and genotypic attributes for better adaptation to the environment. To reveal the diversity of clinical isolates of O1 in the Bay of Bengal, we performed whole-genome sequencing of isolates from Kolkata, India, and Dhaka, Bangladesh, collected between 2009 and 2016.
View Article and Find Full Text PDFIt has been well known that Vibrio cholerae inhabit in environmental water. As many patients infected with cholera toxin-producing V. cholerae O1 (toxigenic V.
View Article and Find Full Text PDFNon-O1/non-O139 nontoxigenic Vibrio cholerae associated with cholera-like diarrhea has been reported in Kolkata, India. However, the property involved in the pathogenicity of these strains has remained unclear. The character of 25 non-O1/non-O139 nontoxigenic V.
View Article and Find Full Text PDFSeveral virulence factors of Aeromonas such as hemolysin, proteases and lipases have been characterized. The relationship between these virulence factors and disease remains unclear. A 71-year-old man underwent thoracoscopic esophagectomy, lymph node dissection and Roux-en-Y reconstruction for esophageal cancer.
View Article and Find Full Text PDFAeromonas sobria is a pathogen causing food-borne illness. In immunocompromised patients and the elderly, A. sobria can leave the intestinal tract, and this opportunistically leads to severe extraintestinal diseases including sepsis, peritonitis, and meningitis.
View Article and Find Full Text PDFThe azithromycin resistance conferred by phosphotransferase is encoded in the gene (A). This gene has been discovered in and reported for many bacterial species. We examined the prevalence of azithromycin resistance in (AR-VF) isolated during 2014 to 2015 from the hospitalized acute diarrheal patients in Kolkata, India.
View Article and Find Full Text PDFBackground: Chloroethylnitrosourea (CENU) derivatives, such as nimustine (ACNU) and carmustine (BCNU), are employed in brain tumor chemotherapy due to their ability to cross the blood-brain barrier. They are thought to suppress tumor development through DNA chloroethylation, followed by the formation of interstrand cross-links (ICLs) that efficiently block replication and transcription. However, the alkylation of DNA and ICLs may trigger genotoxicity, leading to tumor formation as a side effect of the chemotherapeutic treatment.
View Article and Find Full Text PDFAeromonas sobria serine protease (ASP) is an extracellular serine protease secreted by the organism. Here, we identified the amino acid residue of ASP that contributes to substrate specificity by using both synthetic peptides and biological protein components. The results showed that the arginine residue at position 566 (Arg-566) of ASP, which is located in the extra occluding region of ASP close to an entrance of the catalytic cavity, is involved in the substrate specificity.
View Article and Find Full Text PDFMutat Res Genet Toxicol Environ Mutagen
March 2017
Alkylating agents are known to induce the formation of O-alkylguanine (O-alkG) and O-alkylthymine (O-alkT) in DNA. These lesions have been widely investigated as major sources of mutations. We previously showed that mismatch repair (MMR) facilitates the suppression of GC-to-AT mutations caused by O-methylguanine more efficiently than the suppression of GC-to-AT mutations caused by O-ethylguanine.
View Article and Find Full Text PDFIn an attempt to discover inhibitory compounds against pore-forming toxins, some of the major toxins produced by bacteria, we herein examined the effects of four kinds of indolo[3,2-b]quinoline derivatives on hemolysis induced by the aerolysin-like hemolysin (ALH) of Aeromonas sobria and also by the alpha-hemolysin of Staphylococcus aureus. The results showed that hemolysis induced by ALH was significantly reduced by every derivative, while that induced by alpha-hemolysis was significantly reduced by three out of the four derivatives. However, the degrees of reduction induced by these derivatives were not uniform.
View Article and Find Full Text PDFWe examined the properties of exotoxins produced by Aeromonas trota (A. enteropelogenes), one of the diarrheagenic species of Aeromonadaceae. Nine of 19 A.
View Article and Find Full Text PDFWe examined the antifungal activity of various synthetic triamines on several fungi. Among various triamines having a general structure H2N(CH2)aNH(CH2)bNH2 (a=2-5, b=3-8), some triamines (a=4 or 5) showed inhibitory effect on the growth of Candida albicans and C. tropicalis.
View Article and Find Full Text PDFWe examined the ability of Aeromonas hydrophila to lyse elastin. Eight of 13 strains showed elastolytic activity on agar medium containing elastin and 5 strains did not. In order to examine the involvement of the metalloprotease of A.
View Article and Find Full Text PDFDNA alkylation damage can be repaired by nucleotide excision repair (NER), base excision repair (BER) or by direct removal of alkyl groups from modified bases by O(6)-alkylguanine DNA alkyltransferase (AGT; E.C. 2.
View Article and Find Full Text PDFAeromonas have been isolated from a wide variety of aquatic environments. However the number of Aeromonas in sea water is extremely small compared to that in fresh water. In in vitro culture, Aeromonas can grow in mediums containing NaCl at a concentration of 3.
View Article and Find Full Text PDFMicrobiol Immunol
January 2012
A sensitive rRNA-targeted reverse transcription-quantitative polymerase chain reaction (RT-qPCR) method was developed for detection of Vibrio cholerae/mimicus, V. parahaemolyticus/alginolyticus and Campylobacter jejuni/coli by using specific primers. Counts of the enteric pathogens spiked in human stools were quantified at the lower detection limit of 10(3) cells/g stool by RT-qPCR, in marked contrast with conventional quantitative polymerase chain reaction (qPCR) at the detection limit of 10(5) to 10(6) cells/g stool.
View Article and Find Full Text PDFThe present authors have previously shown that the serine protease activity of Aeromonas sobria is markedly decreased when A. sobria is cultured in medium containing 3.0% sodium chloride (NaCl, concentration almost equivalent to sea water salinity), and that this occurs because, although the synthesis of ASP is not disturbed by the salt in the medium, the maturation pathway of serine protease of A.
View Article and Find Full Text PDFPreviously, we cloned the metalloprotease gene of Aeromonas sobria (amp) and determined its nucleotide sequence (GenBank accession number DQ784565). The protease is composed of 591 amino acid residues. In this study, we purified the mature metalloprotease from the culture supernatant of A.
View Article and Find Full Text PDFCandidiasis is a common opportunistic fungal infection that responds well to amphotericin B (AMPH) treatment. However, AMPH often causes adverse effects such as kidney injury and hypokalemia. Because some essential oils have been reported to have antifungal effects, we investigated the antifungal activity of various essential oils and their major constituents against Candida spp.
View Article and Find Full Text PDFASP is the only bacterial protease in the kexin group of the subtilisin family. Previous studies have revealed that the ORF2 protein encoded at the 3' end of the asp operon is required for ASP to change from a nascent form into an active form in the periplasm. However, the mechanism by which ORF2 makes contact and interacts with ASP in the maturation process remains unknown.
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