Involvement of multiple genetic loci in Staphylococcus aureus teicoplanin resistance

Teicoplanin resistance was transformed from a teicoplanin-resistant Staphyl ococcus aureus into the susceptible strain BB255 to give strain BB938. The cell wall composition, amidation of the iD-glutamate, and peptide crosslink ing were identical in BB938 as in BB255 except for a 60% increased length o f the glycan chain. Transductional crosses revealed that at least two disti nct loci contributed in a cumulative fashion to teicoplanin resistance. One of these loci correlated with a mutation inactivating the anti-sigma facto r RsbW. This mutation must have occurred during transformation and selectio n for teicoplanin resistance in BB938. Genetic manipulations involving the sigB operon showed that transcription factor SigB contributed to decreased teicoplanin susceptibility. (C) 2001 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.