Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1980-7-22
pubmed:abstractText
Penicillin kills susceptible bacteria by specifically inhibiting the transpeptidase that catalyzes the final step in cell wall biosynthesis, the cross-linking of peptidoglycan. It was hypothesized (Tipper, D., and Strominger, J. (1965) Proc. Natl. Acad. Sci. U.S.A. 54, 1133-1141) that 1) penicillin is a structural analog of the acyl-D-alanyl-D-alanine terminus of the pentapeptide side chains of nascent peptidoglycan, and that 2) penicillin, by virtue of its highly reactive beta-lactam structure, irreversibly acylates the active site of the cell wall transpeptidase. Although the cell wall transpeptidase has proven elusive, a closely related penicillin-sensitive cell wall enzyme, D-alanine carboxypeptidase, has been purified from membranes of Bacillus stearothermophilus by penicillin affinity chromatography. By amino acid sequence analysis of 14C-labeled cyanogen bromide peptides generated and purified from this carboxypeptidase covalently labeled with either [14C]penicillin G or the substrate, [14C]diacetyl-L-lysyl-D-alanyl-D-lactate, it was shown that the penicillin and substrate were both bound as esters to a serine at residue 36. Therefore, the second hypothesis stated above was proven to be correct for D-alanine carboxypeptidase. Several new methods were developed in the course of this work, including 1) a rapid penicillin-binding assay, 2) use of hydroxylamine to protect peptides against carbamylation during ion exchange chromatography in concentrated urea solutions, and 3) gel filtration chromatography in 70% formic acid, a universal solvent for peptides.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
255
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3977-86
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
The mechanism of action of penicillin. Penicillin acylates the active site of Bacillus stearothermophilus D-alanine carboxypeptidase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.