T-2 toxin was rapidly converted in the 9,000 X g supernatant fraction of rat liver homogenate into HT-2 toxin, T-2 tetraol, and two unknown metabolites designated as TMR-1 and TMR-2. TMR-1 was characterized as 4-deacetylneosolaniol (15-acetoxy-3 alpha, 4 beta, 8 alpha-trihydroxy-12,13-epoxytrichothec-9-ene) by spectroscopic analyses. Since the same metabolites were also obtained from HT-2 toxin...

background and objectives : the rapid emergence and dissemination of carbapenemase-producing klebsiella pneumoniae strains and other members of the enterobacteriaceae poses a considerable threat to the care of hospitalized patients and to public health. the aim of this study was to determine the frequency of metallo-β-lactamases (mbl) and vim-1 gene in multidrug-resistant strains of k. pneumoni...

background: pseudomonas aeruginosa is the causing agent of many hospital infections and metallo-beta-lactamases (mbl) are being reported with increasing frequency. the aim of this study was to determine the frequency of metallo-&beta-lactamases; (mbl) and vim-1 gene in multidrug-resistant strains of p. aeruginosa isolates and to compare the methods of phenotypic and molecular detection. materia...

Background & Aims: One of the most common causes of bacterial resistance to beta-lactam antibiotics is beta-lactamase producing. The aim of this study was to compare the antibiotic resistance of urinary Escherichia coli (E. coli) isolates producing CTX-M and TEM type beta-lactamases, and to determine the strains with co-resistance to multiple antibiotics in Mashhad, Iran. Methods: E. coli b...

Clostridium perfringens is an important pathogen of animals and humans and is the causative agent of necrotic enteritis (NE) in poultry. This study focuses on the typing of intestinal C. perfringens isolates (n = 61) from outbreaks of NE collected from several areas of Southern Ontario, using a recently developed multilocus sequence typing (MLST) technique. For comparison, C. perfringens isolat...

A novel HERG channel blocker was isolated from the venom of the scorpion Buthus martensi Karsch, sequenced and characterized at the pharmacological level after chemical synthesis. According to the determined amino acid sequence, the cDNA and genomic genes were then cloned. The genomic gene consists of two exons interrupted by an intron of 65 bp at position -6 upstream from the mature toxin. The...

Paralytic shellfish poisoning (PSP) is a human foodborne syndrome caused by the consumption of that accumulate paralytic toxins (PSTs, saxitoxin group). In PST-producing dinoflagellates such as Alexandrium spp., toxin synthesis encoded in nuclear genome via gene cluster ( sxt ). Toxin production supposedly associated with presence 4th domain sxtA sxtA4 ), one core genes PST cluster. It postulat...

A novel gene that regulates the alpha-toxin (plc), kappa-toxin (colA), and theta;-toxin (pfoA) genes was identified using toxin-negative mutant strains of Clostridium perfringens. The cloned 3.2-kb fragment contained the virX gene encoding a 51-amino acid polypeptide of unknown function that seemed to be responsible for the activation of toxin genes. The virX knock out mutant of wild-type strai...