This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Madiraju, M V
Right arrow Articles by Wilkinson, B J
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Madiraju, M V
Right arrow Articles by Wilkinson, B J

 Previous Article  |  Next Article 

Antimicrob Agents Chemother. 1987 November; 31(11): 1727-1733

Effects of temperature, NaCl, and methicillin on penicillin-binding proteins, growth, peptidoglycan synthesis, and autolysis in methicillin-resistant Staphylococcus aureus.

M V Madiraju, D P Brunner and B J Wilkinson

Department of Biological Sciences, Illinois State University, Normal 61761.

ABSTRACT

Methicillin-resistant Staphylococcus aureus strains produce a fifth penicillin-binding protein (PBP), PBP 2', with low affinity for beta-lactam antibiotics that is believed to represent a beta-lactam-insensitive peptidoglycan transpeptidase. In an effort to evaluate the adequacy of PBP 2' as an explanation of methicillin resistance, PBP 2' production and the responses of growth and peptidoglycan synthesis to methicillin under different environmental conditions have been compared. In the heterogeneous methicillin-resistant strain DU4916-K7, less PBP 2' was produced at 40 degrees C than at 30 degrees C, but inclusion of 5% (wt/vol) NaCl in the medium at 40 degrees C boosted PBP 2' production and allowed growth of the organism in the presence of 10 micrograms of methicillin per ml. When exponential-phase cultures were challenged with methicillin, growth and peptidoglycan synthesis were much more resistant at 30 degrees C than at 40 degrees C. Inclusion of NaCl in medium rendered growth and peptidoglycan synthesis more methicillin resistant at 40 degrees C. Hence, there was a good correlation between PBP 2' production and methicillin-resistant peptidoglycan synthesis under these conditions. However, PBP 2' production was increased by NaCl at 30 degrees C without markedly affecting the susceptibilities of growth and peptidoglycan synthesis to methicillin. Pregrowth of cells with methicillin, which was expected to boost PBP 2' production, seemed to increase the susceptibilities of growth and peptidoglycan synthesis to methicillin. Patterns of growth and peptidoglycan synthesis susceptibilities to methicillin which were similar to those described above were found in chloramphenicol-inhibited cultures, in which presumably no induction of PBP 2' could occur during the methicillin challenge period. Complex effects were noted in the combination of subinhibitory methicillin and NaCl. Growth of cells in the presence of NaCl stimulated their autolytic activity, which was further increased by growth with subinhibitory methicillin in addition to NaCl. It appears that NaCl enhances methicillin resistance by stimulating PBP 2' production and providing osmotic support but opposes it by stimulating autolytic activity which is exacerbated by the very low cross-linking of peptidoglycan in methicillin-resistant strains grown in the presence of methicillin.


Antimicrob Agents Chemother. 1987 November; 31(11): 1727-1733




This article has been cited by other articles:

  • Sieradzki, K., Chung, M., Tomasz, A. (2008). Role of a Sodium-Dependent Symporter Homologue in the Thermosensitivity of {beta}-Lactam Antibiotic Resistance and Cell Wall Composition in Staphylococcus aureus. Antimicrob. Agents Chemother. 52: 505-512 [Abstract] [Full Text]  
  • Antignac, A., Sieradzki, K., Tomasz, A. (2007). Perturbation of Cell Wall Synthesis Suppresses Autolysis in Staphylococcus aureus: Evidence for Coregulation of Cell Wall Synthetic and Hydrolytic Enzymes. J. Bacteriol. 189: 7573-7580 [Abstract] [Full Text]  
  • Zheng, L., Yu, C., Bayles, K., Lasa, I., Ji, Y. (2007). Conditional Mutation of an Essential Putative Glycoprotease Eliminates Autolysis in Staphylococcus aureus. J. Bacteriol. 189: 2734-2742 [Abstract] [Full Text]  
  • Neuhaus, F. C., Baddiley, J. (2003). A Continuum of Anionic Charge: Structures and Functions of D-Alanyl-Teichoic Acids in Gram-Positive Bacteria. Microbiol. Mol. Biol. Rev. 67: 686-723 [Abstract] [Full Text]  
  • Boyle-Vavra, S., Challapalli, M., Daum, R. S. (2003). Resistance to Autolysis in Vancomycin-Selected Staphylococcus aureus Isolates Precedes Vancomycin-Intermediate Resistance. Antimicrob. Agents Chemother. 47: 2036-2039 [Abstract] [Full Text]  
  • Groicher, K. H., Firek, B. A., Fujimoto, D. F., Bayles, K. W. (2000). The Staphylococcus aureus lrgAB Operon Modulates Murein Hydrolase Activity and Penicillin Tolerance. J. Bacteriol. 182: 1794-1801 [Abstract] [Full Text]  
  • Mir, N., Sánchez, M., Baquero, F., López, B., Calderón, C., Cantón, R. (1998). Soft Salt-Mannitol Agar-Cloxacillin Test: a Highly Specific Bedside Screening Test for Detection of Colonization with Methicillin-Resistant Staphylococcus aureus. J. Clin. Microbiol. 36: 986-989 [Abstract] [Full Text]