Little is known about the role of gut microbiota in response to live oral vaccines against enteric pathogens. We examined the effect of immunization with an oral live-attenuated Shigella dysenteriae 1 vaccine and challenge with wild-type S. dysenteriae 1 on the fecal microbiota of cynomolgus macaques using 16 S rRNA analysis of fecal samples. Multi-dimensional cluster analysis identified differ...

INTRODUCTION Shigellosis, or bacillary dysentery, is a bloody diarrhea caused by the invasion of the human colonic and rectal mucosa by Shigella, a gramnegative microorganism belonging to the family enterobacteriaceae. In the developing world, children are the major victims with 600,000 deaths every year. The symptoms are characterized by early watery diarrhea rapidly followed by fever, intesti...

Shigella species were discovered over 100 years ago by a Japanese microbiologist named Shiga, for whom the genus is named. Shigella organisms are a group of gram-negative, facultative intracellular pathogens. They were recognized as the etiologic agents of bacillary dysentery or shigellosis in the 1890s. These organisms are members of the family Enterobacteriaceae and tribe Escherichieae; they ...

Most (about 81%) of the clinical isolates of shigellae that were tested failed to grow in a minimal medium. Of the auxotrophic isolates belonging to the four Shigella species, 98% grew in a minimal medium containing methionine, nicotinic acid, and tryptophan. The combination of methionine and tryptophan appears to be an obligatory requirement for Shigella dysenteriae serotype 1 strains, while t...

objective: shigellosis is one of the most common causes of morbidity and mortality in children with diarrhea in developing countries. it is essential to assess the antibiotic resistance patterns of these bacteria. ipah gene is one of the virulence factors which can be used for detection of shigella spp. materials and methods: total of 100 isolates of shigella were collected from different prov...

A toxin extracted from heat-inactivated, alkaline-treated Shigella flexneri 2a showed biological properties similar to those of Shigella dysenteria 1 toxin. The S, flexneri 2a toxin was lethal to mice, enterotoxic for ileal loops of rabbits, and cytotoxic for HeLa cells. A serological relationship between S. flexneri 2a and S. dysenteriae 1 toxin was shown with cross neutralization tests.

background: recombinant vaccine technology is one of the most developed means in controlling infectious diseases. however, an effective vaccine against shigella is still missing. objective: to evaluate recombinant ipac protein of shigella as a vaccine candidate. methods: in this study we cloned ipac gene into an expression vector in prokaryotic system. the protein expression was evaluated by sd...

In recent studies, strains of non-dysenteriae 1 Shigella (NDS) expressing Shiga toxin have been reported. In this study, we report a novel stx1a-converting bacteriophage of Shigella sonnei associated with travel to Mexico. Phylogenetic comparison between this and other stx-converting phages suggests that toxigenic NDS strains have arisen through separate horizontal transfer events from toxigeni...

Vaccine candidates against Shigella dysenteriae type 1, which is associated with the most severe cases of bacillary dysentery, were constructed. The rfp and rfb gene clusters, which code for S. dysenteriae 1 O antigen biosynthesis, were randomly integrated into either the chromosome or the virulence plasmid of the rough attenuated Shigella flexneri aroD strain SFL124-27 with a minitransposon ca...

The rfb gene cluster and the rfc gene of Salmonella enterica were introduced earlier into an invasive Shigella dysenteriae 1 strain by triparental cross. Antiserum was raised in rabbit against lipopolysaccharide isolated from the hybrid strain. Both the hybrid and the invasive S. dysenteriae 1 strain were found to have a titer of 1:2560 while for S. enterica, it was 1:640. Ligated ileal loops w...