Temperature-dependent cultural and biochemical characteristics of rhamnose-positive Yersinia enterocolitica

Abstract

Clinical isolates of rhamnose-positive Yersinia enterocolitica (Y.e.rh+) were compared with typical rhamnose-negative Y. enterocolitica (Y.e.rh-) and with Yersinia pseudotuberculosis. The Y.e.rh+ differed from the Y.e.rh- and Y. pseudotuberculosis in their ability to ferment raffinose and lactose, utilize citrate and in their inability to grow on Hektoen enteric agar at 22 or 37 C, on Salmonella-Shigella agar at 37 C, and scant on xylose-lysine-deoxycholate agar at 37 C. An extensive temperature-dependent profile of characteristics was established for the Y.e.rh+: motility, acetoin production, citrate utilization, growth on Salmonella-Shigella agar, and ampicillin resistance occurred at 22 C but not 37 C; fermentation of melibiose, raffinose, and cellobiose occurred within 24 h at 22 C, but not before 5 days at 37 C; fermentation of rhamnose and production of beta-galactosidase occurred within 24 h at 22 C, but not before 48 h at 37 C; greater resistance to ampicillin, chloramphenicol, streptomycin, kanamycin, carbenicillin, and gentamicin was observed at 22 than 37 C; and good growth on xylose-lysine-deoxycholate agar occurred at 22 but not 37 C. For optimal recovery of Y.e.rh+ from mixed culture, e.g., stools, two MacConkey plates should be inoculated and incubated, one at 37 C, and one at 22 C. Lactose-negative colonies appearing after 48 h on the 22 C MacConkey agar but not the 37 C MacConkey agar should be considered possible Y.e.rh+. Biochemicals should be tested in duplicate, one set incubated at 22 C, one set at 37 C. Antibiotic susceptibility tests of Y.e.rh+ isolates should be incubated at both 37 C and at a lower temperature to allow the greatest expression of resistance of these organisms to the various antibiotics.

Comparison of Yersinia enterocolitica DNA Methylation at Ambient and Host Temperatures

“…In V. parahaemolyticus, both an LTTR (AphB) and AphA co-regulate acetoin production and motility [49,50]. Notably, these phenotypes are temperature regulated in Y. enterocolitica, where acetoin and flagella are only produced at a low temperature [51]. The transcriptomic analysis by Bent et al [41], however, reveals little variation in the temperature expression of YE1259.…”

Public Health Hazards of Some Bacterial Pathogens Associated With Consumption of Eggs and Studying the Best Cooking Methods for Their Destruction

“…enterocolitica is found in the chicken faeces and the shell can be contaminated with faeces in the nest or during subsequent manipulation (Berrang et al, 1999). The variation in results could be attributed to the enrichment procedures and the selective media used which fail to recover low levels of clinical strains (Chester and Stotzky, 1976), beside the competition of other contaminants. Listeria spp.…”