pUCV11001, an IncH plasmid isolated in a Escherichia coli strain from a healthy child.

Plasmids conferring resistance to potassium tellurite but not to other antimicrobial agents were detected among E. coli multiresistant strains isolated from healthy children during a survey in Caracas. Few of them were autotransferable to E. coli K12 and they were conjugative only at temperatures below 30 degrees C. They also conferred to the host cells resistance to lethal action of colicin B, PacB character. pUCV11001, a prototype, was classified into the incompatibility group HI, subgroup HI2. Presence of these non-antimicrobial resistant IncH plasmids in E. coli from human sources is indicative of their wide distribution among Enterobacteria in nature.