Mechanisms of chloramphenicol resistance in Haemophilus influenzae in the United Kingdom
Powell, Mair and Livermore, D. M.,, 27, 89-93 (1988),
doi = https://doi.org/10.1099/00222615-27-2-89,
publicationName = Microbiology Society,
issn = 0022-2615,
abstract= SUMMARY Of 2458 isolates of Haemophilus influenzae examined in a recent British survey, 42 were resistant to chloramphenicol. Two resistant isolates were of type b and 40 were non-capsulate. Spectrophotometric assay showed that all the resistant isolates produced chloramphenicol acetyltransferase (CAT). CAT activity did not increase following growth onheated blood agar containing chloramphenicol 2 mg/L but was reduced by 84-98% when extracts were treated for 30 min with 5′, 5′-dithiobis-2-nitrobenzoate. These data suggest thatH. influenzae CATs resemble the Type-II CATs produced by enterobacteria. Extrachromosomal DNA was detected in five only of the 42 resistant isolates and cured derivatives of two plasmid-containing strains retained their chloramphenicol resistance. These results suggest that the CAT gene is located on the chromosome.,
language=,
type=