α-haemolysin (HlyA)-producing Escherichia coli commonly inflict severe urinary tract infections, including pyelonephritis, which comprises substantial risk for sepsis. In vitro, the cytolytic effect of HlyA is mainly mediated by ATP release through the HlyA pore and subsequent P2X1/P2X7 receptor activation. This amplification of the lytic process is not unique to HlyA but is observed by many ot...

Background: Listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic food borne infection. Listeriolysin O is a major virulence factor in this bacterium, which is encoded by hlyA. The aim of the present study was to determine the relation of Listeria monocytogenes hlyA gene isolated from fresh cheese with habitual abortion in Marvdasht. Materials and methods: I...

We have investigated the molecular basis of spontaneous mutations leading to non-hemolytic and avirulent variants of the Listeria monocytogenes serotype 1/2a strain NCTC 7973 using Southern hybridization to DNA fragments that harbor the listeriolysin gene (hlyA) and adjacent regions cloned from a L. monocytogenes serotype 1/2a strain. The analysis of such non-hemolytic variants revealed the pre...

Shiga toxin-producing Escherichia coli (STEC) O157:H7 is an important foodborne pathogen worldwide. In Turkey, little is known about the molecular characteristics of STEC O157:H7 isolates. The aim of this study was to examine the genetic diversity of STEC O157:H7 isolates from cattle in Turkey using pulsed-field gel electrophoresis (PFGE). A total of 18 STEC O157:H7 strains were isolated from 5...

Shiga toxin-producing Escherichia coli (STEC) belonging to certain serogroups (e.g., O157 and O26) can cause serious conditions like hemolytic-uremic syndrome (HUS), but other strains might be equally pathogenic. While virulence factors, like stx and eae, have been well studied, little is known about the prevalence of the E. coli hemolysin genes (hlyA, ehxA, e-hlyA, and sheA) in association wit...

Studies of the Vibrio cholerae population, using molecular typing techniques, have shown the existence of several pathogenic clones, mainly sixth-pandemic, seventh-pandemic, and U.S. Gulf Coast clones. However, the relationship of the pathogenic clones to environmental V. cholerae isolates remains unclear. A previous study to determine the phylogeny of V. cholerae by sequencing the asd (asparta...

BACKGROUND AND OBJECTIVES Shiga toxin-producing Escherichia coli (STEC) have emerged as human pathogens and contamination of foods of animal origin has been a major public health concern. The aim of the present study was to determine the dissemination of STEC in healthy and diarrheic calves in Urmia region which is located in West Azerbaijan province, Iran. MATERIALS AND METHODS In the curren...

We describe an efficient and easy procedure that allows the generation, detection and secretion of foreign proteins by the secretion apparatus of E. coli hemolysin. The gene (or gene fragment) encoding the foreign protein (or protein domain) is inserted in-frame into a residual portion of the hemolysin gene (hlyA), encoding the HlyA secretion signal (HlyAs). Generally, the expressed fusion is e...

background and objectives: shiga toxin-producing escherichia coli ( stec) have emerged as human pathogens and contamination of foods of animal origin has been a major public health concern. the aim of the present study was to determine the dissemination of stec in healthy and diarrheic calves in urmia region which is located in west azerbaijan province, iran. materials and methods: in the curre...