Campylobacter is among the leading causes of bacterial gastroenteritis worldwide. The related disease named campylobacteriosis, affects about 200,000 humans in the European Union each year, which costs about EUR 2.4 billion to public health systems. Despite its impact on human health, this bacteria remains poorly studied and its proteome has not been fully characterized.
The goal of our study was to characterize Cj1169c, a mini-protein from Campylobacter that have never been studied. For this purpose, we cloned the gene Cj1169c in an expression vector in Escherichia coli. Next, we purified the protein which served to produce Cj1169c-specific antibodies that have been used to detect the protein.
Our study has revealed for the first time that Cj1169c is really produced in Campylobacter. We studied the prevalence of this protein in several species of Campylobacter. We found that this protein is only produced in C. jejuni and in C. lari which preferentially colonize birds but not in C. coli (colonizes preferentially pigs). Then, we identified the best growing conditions for Cj1169c protein production. Besides, we demonstrated by several methods that this protein is located in the periplasmic compartment of the bacteria, and could establish via its two cysteines intra- or inter- chain disulfide bridges and may interact with one or more putative partners. According to these data, the Cj1169c protein may be an essential determinant for host colonization.
Soumeya Aliouane, Jean-Marie Pagès, and Jean-Michel Bolla
Aix-Marseille Université, IRBA, TMCD2 UMR-MD1, Faculté de Médecine, 13385 Marseille, France.
e-mail: [email protected]
The Cj1169c-encoded putative protein of Campylobacter was expressed and purified from E. coli after sequence optimization. The purified protein allowed production of a specific rabbit antiserum that was used to study the protein expression in vitro and its subcellular localization in the bacterial cell and putative interactions with other proteins. This protein is produced in Campylobacter and it clearly localizes into the periplasmic space. The level of protein production depends on factors, including pH, temperature, osmolarity and growth phase suggesting a role in the Campylobacter environmental adaptation. The cysteine residues present in the sequence are probably involved in disulfide bridges, which may promote covalent interactions with other proteins of the Campylobacter envelope..Go To Curr Microbiol