Influence of surface polysaccharides of Escherichia coli O157:H7 on plant defense response and survival of the human enteric pathogen on Arabidopsis thaliana and lettuce (Lactuca sativa). (April 2018)

• Record Type: Journal Article
• Authors: Jang, Hyein; Matthews, Karl R.
• Is Part Of: Food microbiology. Volume 70(2018)
• Page Start: 254
• Page End: 261
• Publication Date: 2018-04
• Subjects: E. coli O157:H7 -- Surface polysaccharides -- Produce -- Food safety; Food Microbiology -- Periodicals; Aliments -- Microbiologie -- Périodiques; Food -- Microbiology; Periodicals; Food -- Microbiology -- Periodicals; Food contamination -- Periodicals; 664.001579
• DOI: 10.1016/j.fm.2017.10.013
• Languages: English
• ISSNs: 0740-0020

Abstract

Abstract: This study aimed to determine the influence of bacterial surface polysaccharides (cellulose, colanic acid, and lipopolysaccharide; LPS) on the colonization or survival of Escherichia coli O157:H7 on plants and the plant defense response. Survival of E. coli O157:H7 were evaluated on Arabidopsis thaliana and romaine lettuce as a model plant and an edible crop (leafy vegetable), respectively. The population of the wild-type strain of E. coli O157:H7 on Arabidopsis plants and lettuce was significantly ( P < 0.05) greater compared with the colanic acid-deficient and LPS-truncated mutants on day 1 and day 5 post-inoculation. This result indicates that colanic acid and LPS structures may contribute to the ability of bacterial survival or persistence on plants. The wild-type strain of E. coli O157:H7 produced approximately twice the amount ( P < 0.05) of capsular polysaccharide (CPS) than the colanic acid and LPS-truncated mutants. The significantly lower production of CPS was associated with significantly greater (2-fold) expression of pathogenesis-related gene ( PR1 ) compared with the wild-type and cellulose-deficient mutant ( P < 0.05). Collectively, the results of this study may suggest that specific surface polysaccharides of E. coli O157:H7 differentially induce the plant defense response, consequently affecting the survival of the human pathogen on plants. The survival and persistence of E. coli O157:H7 was similar on Arabidopsis and lettuce regardless of day post-inoculation. Highlights: Surface polysaccharides of E. coli O157:H7 influenced survival ability on plants. Colanic acid and LPS contributed to survival/persistence on Arabidopsis and lettuce. Lower expression of PR1 gene by wild-type E. coli O157:H7 led to greater survival. Capsular polysaccharide may play important roles in pathogen-plant interactions. Comparative study between Arabidopsis and lettuce showed a similar survival trend of E. coli O157:H7.