[Cell wall components of gramicidin S resistant Staphylococcus aureus].
Comparative study of two staphylococcus aureus 209P strains--resistant and susceptible to gramicidin S demonstrated that peptidoglycanes of two strains differ by ratio glycine/serine at peptide bridges. Besides peptidoglycanes significantly differ by amidation of alfa-carboxyles of glutamic acid in muropeptide. This peptidoglycane modification of resistant cells along with enhanced content of etherized D-alanine in teichoic acid provides lower negative charge of cell wall components. It may influence the cell wall ability to react with positively charged gramicidin molecules. It was shown that isolated cell walls and peptidoglycane of resistant cells binds significantly less gramicidin than cell walls and peptodoglyce of susceptable cells. Simultaneous determination of gramicidin binding by intact S. aureus cells and their killing revealed that lower ability of resistant cells to bind gramicidin is significant but not critical factor of gramicidin resistance.
M. V. Lomonosov Moscow State University.
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Orlova
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Bulgakova
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Polin
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002473:Cell Wall / Q000737:chemistry / Q000187:drug effects; D024881:Drug Resistance, Bacterial; D018698:Glutamic Acid / Q000737:chemistry; D005998:Glycine / Q000737:chemistry; D006096:Gramicidin / Q000494:pharmacology*; D010457:Peptidoglycan / Q000032:analysis / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D013211:Staphylococcus aureus / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D013682:Teichoic Acids / Q000737:chemistry / Q000378:metabolism
D000900:Anti-Bacterial Agents; D010457:Peptidoglycan; D013682:Teichoic Acids; D006096:Gramicidin; D018698:Glutamic Acid; D012694:Serine; D005998:Glycine