Campylobacter jejuni carbon starvation protein A (CstA) is involved in peptide utilization, motility and agglutination, and has a role in stimulation of dendritic cells

Abstract

Campylobacter jejuni is the most frequent cause of severe gastroenteritis in the developed world. The major symptom of campylobacteriosis is inflammatory diarrhoea. The molecular mechanisms of this infection are poorly understood compared to those of less frequent disease-causing pathogens. In a previous study, we identified C. jejuni proteins that antibodies in human campylobacteriosis patients reacted with. One of the immunogenic proteins identified (Cj0917) displays homology to carbon starvation protein A (CstA) from Escherichia coli, where this protein is involved in the starvation response and peptide uptake. In contrast to many bacteria, C. jejuni relies on amino acids and organic acids for energy, but in vivo it is highly likely that peptides are also utilized, although their mechanisms of uptake are unknown. In this study, Biolog phenotype microarrays have been used to show that a DcstA mutant has a reduced ability to utilize a number of di-and tri-peptides as nitrogen sources. This phenotype was restored through genetic complementation, suggesting CstA is a peptide uptake system in C. jejuni. Furthermore, the DcstA mutant also displayed reduced motility and reduced agglutination compared to WT bacteria; these phenotypes were also restored through complementation. Murine dendritic cells exposed to UV-killed bacteria showed a reduced IL-12 production, but the same IL-10 response when encountering C. jejuni DcstA compared to the WT strain. The greater Th1 stimulation elicited by the WT as compared to DcstA mutant cells indicates an altered antigenic presentation on the surface, and thus an altered recognition of the mutant. Thus, we conclude that C. jejuni CstA is important not only for peptide utilization, but also it may influence host-pathogen interactions.

Single Cells within the Puerto Rico Trench Suggest Hadal Adaptation of Microbial Lineages

“…This includes genes involved in motility and a number of transporters and permeases for iron, multidrug, sugar, and amino acid transport. These two microbes also share the ability to produce the periplasmic nitrate reductase system protein NapA and encode the carbon starvation protein CstA, which is suggested to be involved in peptide transport under stressed conditions (50).…”

Defining the metabolic requirements for the growth and colonization capacity of Campylobacter jejuni

“…Only ggt -positive C. jejuni strains can efficiently use the tripeptide glutathione as carbon/energy (Hofreuter et al, 2008) and cysteine source (Vorwerk et al, 2014). A recent study using the BIOLOG phenotype microarray technology suggested that the C. jejuni NCTC 11168 transporter protein Cj0917c, which has homology to the carbon starvation protein A (CstA) of E. coli , is involved in the catabolism of several tri- and dipeptides (Rasmussen et al, 2013). Additional experiments are necessary to demonstrate the growth-promoting effect of respective peptides.…”

A novel real-time PCR assay for quantitative detection of Campylobacter fetus based on ribosomal sequences

“…This explains why the 13 isolates used for the description of this subspecies, and the RA8/Italy/2011 strain analyzed here, were negative for Hum’s method based on the cstA gene [10]. Given the importance of this gene in the metabolism of nitrogen, and in the interaction with the host in C. jejuni [37], it is necessary to continue investigating its variations and possible roles in C. fetus .…”