Direct quantitation of the numbers of individual penicillin-binding proteins per cell in Staphylococcus aureus.
The penicillin-binding proteins (PBPs) are a set of enzymes that participate in bacterial peptidoglycan assembly. The absolute numbers of each PBP were determined by direct measurement and have been reported for two Staphylococcus aureus strains, RN4220 (methicillin-sensitive S. aureus) and RN450M (methicillin-resistant S. aureus). From the specific activity of the labeled penicillin and the absolute number of disintegrations per minute, and from the number of CFU per milliliter calculated from proteins and optical density, a determination of the number of PBPs per cell was made. These numbers ranged from approximately 150 to 825 PBPs/cell and represent the first direct determination of absolute numbers of PBPs in S. aureus.
Pucci
Michael J
MJ
Department of Microbiology, Bristol-Myers Squibb Pharmaceutical Research Institute, Wallingford, Connecticut 06492, USA. pucci@bms.com
Dougherty
Thomas J
TJ
D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000378:metabolism*; D003720:Densitometry / Q000379:methods; D006602:Hexosyltransferases; D007553:Isotope Labeling; D007834:Lasers; D016106:Methicillin Resistance; D002267:Muramoylpentapeptide Carboxypeptidase / Q000378:metabolism*; D010400:Penicillin G / Q000378:metabolism*; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D013211:Staphylococcus aureus / Q000254:growth & development / Q000378:metabolism*; D014316:Tritium
D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D014316:Tritium; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase; D010400:Penicillin G