Mutant analysis shows that alanine racemases from Pseudomonas aeruginosa and Escherichia coli are dimeric.
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ABSTRACT:
SUBMITTER: Strych U
PROVIDER: S-EPMC135199 | biostudies-literature | 2002 Aug
REPOSITORIES: biostudies-literature
Publications
Mutant analysis shows that alanine racemases from Pseudomonas aeruginosa and Escherichia coli are dimeric.
Strych Ulrich U Benedik Michael J MJ
Journal of bacteriology 20020801 15
Alanine racemases are ubiquitous prokaryotic enzymes providing the essential peptidoglycan precursor D-alanine. We present evidence that the enzymes from Pseudomonas aeruginosa and Escherichia coli function exclusively as homodimers. Moreover, we demonstrate that expression of a K35A Y235A double mutation of dadX in E. coli suppresses bacterial growth in a dominant negative fashion. ...[more]
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