TABLE 4.
Hybridization analysis and transfer frequencies of VREF from a single institution in southeastern Michigan
| Strain type(s) | No. of isolates | Vancomycin genotype (location) | Transfer frequencya | Yr(s) cultured |
|---|---|---|---|---|
| M29 | 1 | B (chromosome) | <10−9 | 1991 |
| M30 | 1 | A (chromosome) | 10−4 | 1992 |
| M8 | 2 | B (chromosome) | <10−9 | 1992 |
| M1 | 25 | A (chromosome) | 10−5–10−8 | 1993–1996 |
| M3 | 9 | A (6 on chromosome, 3 on plasmid) | 10−5–10−9 | 1994–1996 |
| M6 | 2 | A (chromosome) | 10−6 | 1995 |
| M4 | 21 | A (5 on chromosome, 16 on plasmid) | 10−5–10−9 | 1995–1996 |
| M10 | 14 | A (chromosome) | 10−4–10−6 | 1995–1996 |
| M7, -22, -33, -40, -41, -42, -43, -49, -51, -54, -58, -61, -62 | 1 (each) | A (chromosome) | 10−5–10−8 | 1995–1996 |
| M23, -34, -60 | 1 (each) | B (chromosome) | <10−9 | 1995–1996 |
| M11 | 4 | A (plasmid) | 10−6–10−7 | 1996 |
| M9 | 2 | B (chromosome) | <10−9 | 1996 |
| M12, -14, -25, -55, -57, -63 | 1 (each) | A (plasmid) | 10−5–<10−9 | 1996 |
a
Transfer into plasmid-free E. faecium GE-1.