Distribution of R Plasmids Among the O-Antigen Types of Escherichia coli Isolated from Human and Animal Sources

Abstract

The 0-antigen types of 600 independently isolated Escherichia coli strains from human feces have been determined, and the types have been related to the antibiotic resistance pattems of the strains. The relative abundance of each 0-antigen type differed in the susceptible and resistant series of strains. The majority (86%) of the resistant strains carried R plasmids. Resistant E. coli (20.3%) were found associated with 0-antigen types 8, 9 and 101, whereas the susceptible strains covered a wide range of 0-antigen types. Examination of 174 resistant strains isolated from calf feces also showed a prevalence of 0-antigen types 8, 9, 101 (24.1%), and it seems probable that strains expressing these three 0-antigen types commonly carry R plasmids in the alimentary tracts of man and calves. The number of strains not typeable with the 0 sera available were similar in the human (12.5%) and the calf (11.5%) series. There are no grounds for distinguishing "human" from "calf' E. coli on the basis of their 0-antigen reactions.

Characteristics of Antibiotic-Resistant Escherichia Coli In the Rectum of Healthy School-Children

“…Of antibiotic-resistant E. coli isolates from calves, Hartley et al (1975) found that the 0-groups 8, 9 and 101 accounted for 24%. In human clinical isolates, the 0-group distribution differed between the antibiotic-resistant and sensitive strains (Petrocheilou and Richmond, 1976), groups 8, 9, 17 and 101 being considerably more common among the resistant E. coli, whether or not known to be carrying plasmids.…”

Microbial Source Tracking: Current Methodology and Future Directions

“…Serogrouping of microorganisms based on the presence of different somatic (O) antigenic determinants has been used by several investigators to differentiate E. coli from various sources (17,28). It has been reported that different serotypes of E. coli are associated with different animal sources, although many serotypes are also shared among humans and animals (8,33,55). Parveen et al (58) tested a total of 100 human source and nonhuman source E. coli isolates for the presence of various O antigens.…”

Persistence of Plasmid-Carrying Tetracycline-Resistant Escherichia coli in a Married Couple, One of Whom Was Receiving Antibiotics

“…The method used was based on that described by Wiedemann and Knothe (9). The modifications have been described previously (4). We define majority strains as E. coli strains that occurred at least once among the 10 colonies picked from the non-selective agar (4,6).…”