Insights into the Virulence of Campylobacter jejuni Associated with Two-Component Signal Transduction Systems and Single Regulators

Abstract

Campylobacter jejuni is one of the major aetiologies of diarrhoea. Understanding the processes and virulence factors contributing to C. jejuni fitness is a cornerstone for developing mitigation strategies. Two-component signal transduction systems, known as two-component systems (TCSs), along with single regulators with no obvious cognate histidine kinase, help pathogens in interacting with their environments, but the available literature on C. jejuni is limited. A typical TCS possesses histidine kinase and response regulator proteins. The objective of this review was to provide insights into the virulence of C. jejuni associated with TCSs and single regulators. Despite limited research, TCSs are important contributors to the pathogenicity of C. jejuni by influencing motility (FlgSR), colonisation (DccRS), nutrient acquisition (PhosSR and BumSR), and stress response (RacRS). Of the single regulators, CbrR and CosR are involved in bile resistance and oxidative stress response, respectively. Cross-talks among TCSs complicate the full elucidation of their molecular mechanisms. Although progress has been made in characterising C. jejuni TCSs, shortfalls such as triggering signals, inability to induce mutations in some genes, or developing suitable in vivo models are still being encountered. Further research is expected to shed light on the unexplored sides of the C. jejuni TCSs, which may allow new drug discoveries and better control strategies.

Microbial Metabolite Trimethylamine N-Oxide PromotesCampylobacter jejuniInfection by Escalating Intestinal Inflammation, Epithelial Damage, and Barrier Disruption

“…According to the CDC, there are about 1.5 million cases of Campylobacter infection each year resulting in an economic cost between $1.3 to $6.8 billion annually in the USA. C. jejuni has rapidly developed multiple mechanisms of antibiotic resistance all over the world 3,4 . Hence, the CDC designated the drug-resistant Campylobacter strains as a “serious antibiotic resistance threat.” Therefore, C.jejuni warrants deeper investigation into the mechanisms of its pathogenesis, which may allow the development of potential therapeutic agents against it.…”

“…To establish infection and cause gastroenteritis in humans, C. jejuni employs a repertoire of factors, which include flagella for chemotaxis and colonization of the mucus layer, several adhesins and other proteins for adherence and invasion of cells, as well as a single exotoxin called cytolethal distending toxin (CDT) 4,11 . In addition, C. jejuni disrupts epithelial paracellular junctions in several ways, including secreting serine protease HtrA, switching claudin isoforms, or redistributing TJ protein cellular location 12 .…”

CemR atypical response regulator impacts energy conversion inCampylobacteria

“…According to the MiST database [7], C. jejuni NCTC 11168 (1.64 Mbp; 1643 coding sequences [8]) and A. butzleri RM4018 (2.34 Mbp, 2259 coding sequences [9]) encode 56 and 218 signal transduction proteins, respectively. While A. butzleri regulatory systems have been hardly studied [10], the C. jejuni signal transduction systems have been partially deciphered [11][12][13][14][15]. Particular interest was directed to studying processes related to the C. jejuni colonization and focused on factors controlling the expression of genes involved in such processes as host adaptation and niche detection (BumSR, DccSR), oxidative stress (e.g., CosR, PerR), metabolism, and respiration (e.g., BumSR, RacSR, CosR, CsrA, LysR (Cj1000), CprSR) [11,[13][14][15].…”

“…While A. butzleri regulatory systems have been hardly studied [10], the C. jejuni signal transduction systems have been partially deciphered [11][12][13][14][15]. Particular interest was directed to studying processes related to the C. jejuni colonization and focused on factors controlling the expression of genes involved in such processes as host adaptation and niche detection (BumSR, DccSR), oxidative stress (e.g., CosR, PerR), metabolism, and respiration (e.g., BumSR, RacSR, CosR, CsrA, LysR (Cj1000), CprSR) [11,[13][14][15]. Notably, aerobic or microaerophilic respiration, in which oxygen is used as a terminal electron acceptor, is far more efficient in supplying energy than anaerobic respiration or fermentation [16].…”

“…A. butzleri RM4018 (2.34 Mbp, 2259 coding sequences) encodes 218 signal transduction proteins, including 82 OCS, 32 HK and 43 RR of the TCS 7,10 . While A. butzleri regulatory systems have been hardly studied 11 , the C. jejuni signal transduction systems have been partially deciphered [12][13][14][15][16]…”