Penicillin-binding protein gene alterations in Streptococcus uberis isolates presenting decreased susceptibility to penicillin.

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Serval ID
serval:BIB_95A97598C7F8
Type
Article: article from journal or magazin.
Collection
Publications
Title
Penicillin-binding protein gene alterations in Streptococcus uberis isolates presenting decreased susceptibility to penicillin.
Journal
Antimicrobial Agents and Chemotherapy
Author(s)
Haenni M., Galofaro L., Ythier M., Giddey M., Majcherczyk P., Moreillon P., Madec J.Y.
ISSN
1098-6596 (Electronic)
ISSN-L
0066-4804
Publication state
Published
Issued date
2010
Volume
54
Number
3
Pages
1140-1145
Language
english
Abstract
Streptococcus uberis is an environmental pathogen commonly causing bovine mastitis, an infection that is generally treated with penicillin G. No field case of true penicillin-resistant S. uberis (MIC > 16 mg/liter) has been described yet, but isolates presenting decreased susceptibility (MIC of 0.25 to 0.5 mg/liter) to this drug are regularly reported to our laboratory. In this study, we demonstrated that S. uberis can readily develop penicillin resistance in laboratory-evolved mutants. The molecular mechanism of resistance (acquisition of mutations in penicillin-binding protein 1A [PBP1A], PBP2B, and PBP2X) was generally similar to that of all other penicillin-resistant streptococci described so far. In addition, it was also specific to S. uberis in that independent resistant mutants carried a unique set of seven consensus mutations, of which only one (Q(554)E in PBP2X) was commonly found in other streptococci. In parallel, independent isolates from bovine mastitis with different geographical origins (France, Holland, and Switzerland) and presenting a decreased susceptibility to penicillin were characterized. No mosaic PBPs were detected, but they all presented mutations identical to the one found in the laboratory-evolved mutants. This indicates that penicillin resistance development in S. uberis might follow a stringent pathway that would explain, in addition to the ecological niche of this pathogen, why naturally occurring resistances are still rare. In addition, this study shows that there is a reservoir of mutated PBPs in animals, which might be exchanged with other streptococci, such as Streptococcus agalactiae, that could potentially be transmitted to humans.
Keywords
Animals, Cattle, Cattle Diseases/microbiology, Female, Humans, Mastitis, Bovine/microbiology, Microbial Sensitivity Tests, Mutation, Penicillin Resistance/genetics, Penicillin-Binding Proteins/genetics, Penicillin-Binding Proteins/metabolism, Penicillins/pharmacology, Streptococcal Infections/microbiology, Streptococcal Infections/veterinary, Streptococcus/drug effects, Streptococcus/genetics
Pubmed
Web of science
Open Access
Yes
Create date
17/02/2010 18:40
Last modification date
08/05/2019 22:17
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