Motility and biofilm formation of the emerging gastrointestinal pathogenCampylobacter concisusdiffers under microaerophilic and anaerobic environments

Abstract

Campylobacter concisus has been isolated from patients with gastroenteritis and inflammatory bowel disease (IBD), as well as healthy subjects. While strain differences may plausibly explain virulence differentials, an alternative hypothesis posits that the pathogenic potential of this species may depend on altered ecosystem conditions in the inflamed gut. One potential difference is oxygen availability, which is frequently increased under conditions of inflammation and is known to regulate bacterial virulence. Hence, we hypothesized that oxygen influences C. concisus physiology. We therefore characterized the effect of microaerophilic or anaerobic environments on C. concisus motility and biofilm formation, two important determinants of host colonization and dissemination. C. concisus isolates (n D 46) sourced from saliva, gut mucosal biopsies and feces of patients with IBD (n D 23), gastroenteritis (n D 8) and healthy subjects (n D 13), were used for this study. Capacity to form biofilms was determined using crystal violet assay, while assessment of dispersion through soft agar permitted motility to be assessed. No association existed between GI disease and either motility or biofilm forming capacity. Oral isolates exhibited significantly greater capacity for biofilm formation compared to fecal isolates (p < 0.03), and showed a strong negative correlation between motility and biofilm formation (r D ¡0.7; p D 0.01). Motility significantly increased when strains were cultured under microaerophilic compared to anaerobic conditions (p < 0.001). Increased biofilm formation under microaerophillic conditions was also observed for a subset of isolates. Hence, differences in oxygen availability appear to influence key physiological aspects of the opportunistic gastrointestinal pathogen C. concisus.

Diurnal and eating-associated microbial patterns revealed via high-frequency saliva sampling

“…Campylobacter concisus normally grows under anaerobic conditions ( Lee et al 2014 ). Ovesen et al (2019) revealed that its motility, which was negatively correlated with biofilm forming capacity, was significantly increased under microaerophilic conditions compared to anaerobic environments. Speculatively, the increase of Campylobacter concisus in saliva might be related to fluctuations in oxygen exposure during eating, leading to its high motility and dislodging from oral surfaces.…”

Review on Stress Tolerance in Campylobacter jejuni

“…C. jejuni can generate biofilms in liquid media as a monospecies ( Sałamaszyńska-Guz et al, 2018 ) in aerobic conditions ( Ovesen et al, 2019 ) C. jejuni can form biofilms both as a monospecies and as a combination of microbes ( The et al, 2019 ) and nutritional components ( Bronnec et al, 2016 ). Sałamaszyńska-Guz et al (2018) showed that the aggregating and pellicle form of C. jejuni that forms at 30–37°C in a microaerobic environment allows the bacteria to survive under aerobic conditions.…”

“… Sałamaszyńska-Guz et al (2018) showed that the aggregating and pellicle form of C. jejuni that forms at 30–37°C in a microaerobic environment allows the bacteria to survive under aerobic conditions. Ovesen et al (2019) demonstrated that C. jejuni easily creates biofilms, and that flagellar motility aggravated biofilm production. It currently reads as though it is the report of Ovesen et al, 2019 stated that C. jejuni could acclimate to develop a biofilm linked to CsrA under aerobic conditions ( Askoura et al, 2016 ; Ye et al, 2019 ).…”

“… Ovesen et al (2019) demonstrated that C. jejuni easily creates biofilms, and that flagellar motility aggravated biofilm production. It currently reads as though it is the report of Ovesen et al, 2019 stated that C. jejuni could acclimate to develop a biofilm linked to CsrA under aerobic conditions ( Askoura et al, 2016 ; Ye et al, 2019 ). Therefore, CsrA mutation leads to inhibition of biofilm formation ( Fields and Thompson, 2008 ).…”

“…All species of the genus Campylobacter , with the exception of Campylobacter gracilis (nonmotile) and Campylobacter showae (peritrichous flagella), have a single, polar, unsheathed flagellum on one or both sides of the cell. Infection with Campylobacter in humans predominantly occurs through handling and ingestion of Campylobacter -contaminated raw or undercooked meat, raw milk, tap water, chicken salad, and various chicken-containing dishes ( Zhao et al, 2003 ; Jang et al, 2007 ; Pedersen et al, 2018 ; Ovesen et al, 2019 ; The et al, 2019 ) as illustrated in Figure 1 . Most Campylobacter infections involve a mild and self-limiting gastroenteritis, with one to three days of fever and vomiting, followed by abdominal pain with watery or bloody diarrhea for three to seven days ( Negretti et al, 2019 ).…”