A GENE CONFERRING RESISTANCE TO VANCOMYCIN BUT NOT TEICOPLANIN IN ISOLATES OF ENTEROCOCCUS-FAECALIS AND ENTEROCOCCUS-FAECIUM DEMONSTRATES HOMOLOGY WITH VANB, VANA, AND VANC GENES OF ENTEROCOCCI

We report the sequence of a 630-bp fragment of a gene associated with resistance to high levels of vancomycin in a clinical isolate of Enter ococcus faecalis which retained susceptibility to teicoplanin. This ge ne was similar to the recently sequenced vanB and partially homologous with vanA, but it showed less-marked similarity to vanC. A DNA probe, derived from this polymerase chain reaction-amplified gene fragment, hybridized specifically with genomic DNA from Enterococcus faecium and E. faecalis isolates which were vancomycin resistant (MICs ranged fro m 8 to 512 mug/ml) but susceptible to teicoplanin. Curing of vancomyci n resistance was associated with loss of DNA hybridization with the ge ne probe. Transfer of DNA which hybridized with the probe accompanied transfer of vancomycin resistance to a susceptible recipient strain. N either curing nor transfer of vancomycin resistance was consistently r elated to loss or acquisition, respectively, of plasmid DNA.