porins from salmonella typhi 0-901 and salmonella typhimurium ra-30 were characterized and compared. the elution profile of porins from these salmonella species on sepharose-48 and hplc appear to be very similar. the findings were confirmed by the electrophoretic pattern which showed three types of porins, i.e. ompc, ompd and ompf in both species. these porins appear to be similar, if not ident...

Salmonella typhi 5076-IC, which contains a plasmid that encodes the form I antigen of Shigella sonnei and which expresses S. typhi 9 and 12 and S. sonnei form I antigens, was used to immunize rabbits via chronically isolated ileal loops. Intestinal immunoglobulin A activity was detected against S. typhi, S. sonnei form I, and S. typhi strain 5076-IC. Thus S. typhi 5076-IC can effectively elicit...

background: salmonella is one of the major causes of human diseases related to food consumption. salmonella typhi and s. para-typhi are causes of typhoidal and para-typhoidal infections. some infected individuals recovering from this infection become temporary or permanent carriers, harboring the organisms in the gallbladder, biliary tract, or rarely in their intestines. the aims of this study ...

Expression of the Escherichia coli OmpC and OmpF outer membrane proteins is regulated by the osmolarity of the culture media. In contrast, expression of OmpC in Salmonella typhi is not influenced by osmolarity, while OmpF is regulated as in E. coli. To better understand the lack of osmoregulation of OmpC expression in S. typhi, we compared the expression of the ompC gene in S. typhi and E. coli...

pR(ST98), a chimeric plasmid isolated from Salmonella enterica serovar typhi (S. typhi), is involved in bacterial multidrug-resistance and virulence, however, its exact contributions to bacterial pathogenesis are still not fully understood. To investigate whether pR(ST98) exhibits potential to mediate macrophage autophagy and apoptosis, murine macrophage-like cell line (J774A.1) was infected wi...

BACKGROUND Salmonella enterica serovar Typhi (S. Typhi) exhibits unique characteristics as an intracellular human pathogen. It causes both acute and chronic infection with various disease manifestations in the human host only. The principal factors underlying the unique lifestyle of motility and biofilm forming ability of S. Typhi remain largely unknown. The main objective of this study was to ...

Typhoid fever, caused by Salmonella enterica serovar Typhi (S. Typhi), remains a serious global health concern. Since their emergence in the mid-1970s multi-drug resistant (MDR) S. Typhi now dominate drug sensitive equivalents in many regions. MDR in S. Typhi is almost exclusively conferred by self-transmissible IncHI1 plasmids carrying a suite of antimicrobial resistance genes. We identified o...

background: salmonella enterica serovar typhi (s. typhi) the cause of the acute febrile disease typhoid fever is the major public health problem in developing countries. asymptomatic carriers are the main sources of typhoid. the aim of this study was to investigate methods for isolation and identification of s. typhi in asymptomatic carriers. materials and methods: two hundred stool samples wer...

Strains of the various Salmonella enterica serovars cause gastroenteritis or typhoid fever in humans, with virulence depending on the action of two type III secretion systems (Salmonella pathogenicity island 1 [SPI-1] and SPI-2). SptP is a Salmonella SPI-1 effector, involved in mediating recovery of the host cytoskeleton postinfection. SptP requires a chaperone, SicP, for stability and secretio...

OBJECTIVES To define the genetic characteristics and resistance mechanisms of clinical isolates of Salmonella enterica serovar Typhi (S. Typhi) and S. enterica serovar Paratyphi A (S. Paratyphi A) exhibiting high-level fluoroquinolones resistance. METHODS Three S. Typhi and two S. Paratyphi A ciprofloxacin-resistant isolates (MICs > 4 mg/L) were compared with isolates with reduced susceptibil...