|
rdf:type |
|
|
lifeskim:mentions |
|
|
pubmed:issue |
1
|
|
pubmed:dateCreated |
1998-3-27
|
|
pubmed:abstractText |
High level methicillin resistance in Staphylococcus aureus is dependent upon the acquisition of the mecA gene encoding penicillin-binding protein 2a (PBP2a). PBP2a is a member of a family of peptidoglycan biosynthetic enzymes involved in assembly of the cell wall in bacteria and is poorly inactivated by beta-lactam antibiotics. We describe a 96-well-filter binding assay using recombinant, soluble PBP2a which allows for kinetic measurement of penicillin binding. The deacylation rate constant for the PBP2a-penicillin G covalent complex was found to be 5.7 +/- 1.0 x 10(-5) s-1 at 30 degrees C (half-life of approximately 200 min). For the PBP2a acylation reaction, the value of K(m) (penicillin G) = 0.5 +/- 0.1 mM and kcat = 1 x 10(-3) s-1, which yields a second-order rate constant (kcat/K(m)) for inactivation of 2.0 M-1 s-1. Using this assay, several non-beta-lactam inhibitors including Cibacron blue have been found which exhibit IC50 values between 10 and 30 microM. The binding affinities of several carbapenems and beta-lactams correlated well between the filter binding assay described in this report and an electrophoretic assay for PBP2a using membranes prepared form methicillin-resistant S. aureus.
|
|
pubmed:language |
eng
|
|
pubmed:journal |
|
|
pubmed:citationSubset |
IM
|
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Anti-Bacterial Agents,
http://linkedlifedata.com/resource/pubmed/chemical/Bacterial Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Carbapenems,
http://linkedlifedata.com/resource/pubmed/chemical/Carrier Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Cibacron Blue F 3GA,
http://linkedlifedata.com/resource/pubmed/chemical/Dimethyl Sulfoxide,
http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors,
http://linkedlifedata.com/resource/pubmed/chemical/Hexosyltransferases,
http://linkedlifedata.com/resource/pubmed/chemical/Imidazoles,
http://linkedlifedata.com/resource/pubmed/chemical/Imipenem,
http://linkedlifedata.com/resource/pubmed/chemical/L 695256,
http://linkedlifedata.com/resource/pubmed/chemical/Muramoylpentapeptide...,
http://linkedlifedata.com/resource/pubmed/chemical/Penicillin G,
http://linkedlifedata.com/resource/pubmed/chemical/Penicillin-Binding Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Peptidyl Transferases,
http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Triazines,
http://linkedlifedata.com/resource/pubmed/chemical/Tritium
|
|
pubmed:status |
MEDLINE
|
|
pubmed:month |
Jan
|
|
pubmed:issn |
0003-2697
|
|
pubmed:author |
|
|
pubmed:issnType |
Print
|
|
pubmed:day |
1
|
|
pubmed:volume |
255
|
|
pubmed:owner |
NLM
|
|
pubmed:authorsComplete |
Y
|
|
pubmed:pagination |
113-9
|
|
pubmed:dateRevised |
2009-11-19
|
|
pubmed:meshHeading |
pubmed-meshheading:9448849-Anti-Bacterial Agents,
pubmed-meshheading:9448849-Bacterial Proteins,
pubmed-meshheading:9448849-Binding, Competitive,
pubmed-meshheading:9448849-Binding Sites,
pubmed-meshheading:9448849-Biotechnology,
pubmed-meshheading:9448849-Carbapenems,
pubmed-meshheading:9448849-Carrier Proteins,
pubmed-meshheading:9448849-Chemical Precipitation,
pubmed-meshheading:9448849-Dimethyl Sulfoxide,
pubmed-meshheading:9448849-Enzyme Inhibitors,
pubmed-meshheading:9448849-Hexosyltransferases,
pubmed-meshheading:9448849-Imidazoles,
pubmed-meshheading:9448849-Imipenem,
pubmed-meshheading:9448849-Kinetics,
pubmed-meshheading:9448849-Methods,
pubmed-meshheading:9448849-Micropore Filters,
pubmed-meshheading:9448849-Muramoylpentapeptide Carboxypeptidase,
pubmed-meshheading:9448849-Penicillin G,
pubmed-meshheading:9448849-Penicillin-Binding Proteins,
pubmed-meshheading:9448849-Peptidyl Transferases,
pubmed-meshheading:9448849-Recombinant Proteins,
pubmed-meshheading:9448849-Sensitivity and Specificity,
pubmed-meshheading:9448849-Solubility,
pubmed-meshheading:9448849-Triazines,
pubmed-meshheading:9448849-Tritium
|
|
pubmed:year |
1998
|
|
pubmed:articleTitle |
Soluble penicillin-binding protein 2a: beta-lactam binding and inhibition by non-beta-lactams using a 96-well format.
|
|
pubmed:affiliation |
Department of Biochemistry, Merck Research Laboratories, Rahway, New Jersey 07065-0900, USA. jeff_toney@merck.com
|
|
pubmed:publicationType |
Journal Article,
Comparative Study
|
