Primary structure and function of a cytotoxic outer-membrane protein (ComP) of Plesiomonas shigelloides

Abstract

We previously isolated and characterized a 40-kDa cytotoxic outer-membrane protein (ComP) produced by Plesiomonas shigelloides strain P-1 (P-1). Sequence analysis of the comP gene revealed a coding region of 1068 bp, with a predicted mature protein composed of 335 amino acids and a molecular mass of 38.597 kDa. Three-dimensional structural modeling of ComP suggests that it has a beta-barrel structure with 16 transmembrane strands, eight short periplasmic turns and eight external loops. blast search results and protein modeling suggest that ComP may be a novel porin protein of P. shigelloides. In order to understand the role of ComP during P. shigelloides infection, we constructed a deletion mutant strain (P. shigelloides DeltacomP; P-1201), and compared the pathogenicity of P-1201 vs. the wild-type strain P-1 in Caco-2 cells. Unlike P-1, the deletion strain P-1201 was not cytotoxic to Caco-2 cells and did not lead to apoptosis. These data indicate that ComP may be the predominant virulence factor that triggers cell death in the host cells following infection.

Comparative analysis of Klebsiella pneumoniae genomes identifies a phospholipase D family protein as a novel virulence factor

“…Potential pathogenesis-related genes coded for a putative cytotoxic outer membrane protein (cOMP, KpST66_4736) and a polyamine ABC transport system (KpST66_4729 to KpST66_4732). cOMP closest known homologue (34% identity) was a Plesiomonas shigelloides predominant virulence factor proposed to trigger cell death in host cells following infection [57]. Polyamine biosynthesis and transport mechanisms were intricately linked to fitness, survival, biofilm formation and pathogenesis, for instance in S. pneumoniae and Yersinia pestis [58,59].…”

Plesiomonas shigelloides Revisited

“…However, they observed that both a wildtype strain and a mutant strain with a comP deletion were not insignificantly different in their abilities to internalize and multiply within Caco-2 cells. This observation suggests that apoptosis associated with ComP is not involved in the internalization and growth within the host cells (198).…”

Effects of Quercetin on the Intestinal Microflora of Freshwater Dark Sleeper Odontobutis potamophila

“…An experiment studying growth-related gut microbes in discus fish ( Symphysodon haraldi ) [ 49 ] found that Lactococcus promotes fish growth, whereas Plesiomonas restricts it. The pathogenic bacterium Plesiomonas shigelloides is the only species in the genus Plesiomonas and is known to cause fish diseases, as in references [ 50 , 51 ], which studied the structure and function of the cytotoxic outer membrane protein (ComP) of P. shigelloides and found that ComP may contribute to host cell death.…”