Linked Life Data

10837472

Source:http://linkedlifedata.com/resource/pubmed/id/10837472

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
35
pubmed:dateCreated
2000-10-3
pubmed:abstractText
The reactions of class A beta-lactamases PC1 and TEM-1 with tazobactam (TZB), a potent penicillanic sulfone inhibitor for class A beta-lactamases, were studied using electrospray ionization mass spectrometry (ESI/MS). Following inactivation of the beta-lactamases by TZB, new abundant high mass components were observed including three with molecular masses of 52, 70, and 88 Da greater than PC1 and TEM-1, respectively, and a component with a molecular mass of 300 Da greater than PC1. In addition, three TZB reaction products with molecular masses of 248, 264, and 280 Da were observed. High performance liquid chromatography (HPLC)/ESI/MS analysis of the TZB-PC1 adduct digested with Glu-C revealed three new components with masses 52, 70, and 88 Da greater than that of the peptide composed of amino acid residues 58-82 and one new component with a mass 70 Da greater than that of the peptide composed of amino acid residues 125-141. HPLC/ESI/MS/MS analysis of the two digested peptides whose masses increased by 70 Da indicated that Ser-70 and Ser-130 were the most likely TZB-modified amino acid residues. Based on these data, a mechanism for the inactivation of the class A beta-lactamases by TZB is proposed. In this scheme, initial acylation of Ser-70 by TZB and opening of the lactam ring are followed by one of several different events: (1) the rapid decomposition of TZB with loss of the enamine moiety to form the propiolylated enzyme, (2) an intramolecular nucleophilic displacement of the imine or enamine moiety by Ser-130 to form a cross-linked vinyl ether, and (3) hydrolysis of the imine or enamines to form a Ser-70-linked aldehyde.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26674-82
pubmed:dateRevised
2008-8-22
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Mechanism of inhibition of the class A beta -lactamases PC1 and TEM-1 by tazobactam. Observation of reaction products by electrospray ionization mass spectrometry.
pubmed:affiliation
Wyeth-Ayerst Research, Pearl River, New York 10965, USA. yangy@war.wyeth.com
pubmed:publicationType
Journal Article