Open AccessA chromosomal chloramphenicol acetyltransferase determinant from a probiotic strain of Bacillus clausii
Author(s) -
Galopin Sébastien,
Cattoir Vincent,
Leclercq Roland
Publication year - 2009
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2009.01633.x
Subject(s) - chloramphenicol , chloramphenicol acetyltransferase , biology , microbiology and biotechnology , gene , antibiotics , genetics , gene expression , reporter gene
The mechanism of resistance to chloramphenicol was studied in four strains of Bacillus clausii included in a probiotic mixture, which is administered to humans for prevention of gastrointestinal side effects due to oral antibiotic therapy. By cloning experiments, a chloramphenicol acetyltransferase (CAT) gene, cat Bcl , coding for a putative 228‐amino acid CAT protein was identified in B. clausii SIN. The deduced amino acid sequence displayed from 31% to 85% identity with 56 CAT proteins from other Gram‐positive bacterial strains. The cat Bcl gene was also detected by PCR in the three other B. clausii strains resistant to chloramphenicol, whereas it was absent in the three control strains susceptible to chloramphenicol. Pulse‐field gel electrophoresis of total DNA digested by I‐CeuI followed by hybridization with a cat ‐specific probe as well as unsuccessful repeated attempts of in vitro transfer of chloramphenicol resistance to various recipient cells indicated that cat Bcl was chromosomally located in all four resistant B. clausii strains.