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Arabidopsis thaliana mitochondrial glyoxalase 2-1 exhibits beta-lactamase activity.

ABSTRACT: In an effort to determine the physiological role of Arabidopsis thaliana Glx2-1, we attempted to uncover a substrate for the enzyme. Glx2-1 did not effectively process 192 diverse substrates found in a commercial screen used for microorganism identification or exhibit arylsulfatase, lactonase, or phosphotriesterase activities. However, Glx2-1 does exhibit beta-lactamase activity with k(cat)/KM values from 10(3) to 10(5) M(-1) s(-1). Glx2-1 can hydrolyze cephalosporins and carbapenems, albeit with rate constants slower than those of most metallo-beta-lactamases. The potential role of a beta-lactamase in the mitochondria of plant cells is briefly discussed.

SUBMITTER: Limphong P

PROVIDER: S-EPMC2747047 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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Arabidopsis thaliana mitochondrial glyoxalase 2-1 exhibits beta-lactamase activity.

Limphong Pattraranee P Nimako George G Thomas Pei W PW Fast Walter W Makaroff Christopher A CA Crowder Michael W MW

Biochemistry 20090901 36

In an effort to determine the physiological role of Arabidopsis thaliana Glx2-1, we attempted to uncover a substrate for the enzyme. Glx2-1 did not effectively process 192 diverse substrates found in a commercial screen used for microorganism identification or exhibit arylsulfatase, lactonase, or phosphotriesterase activities. However, Glx2-1 does exhibit beta-lactamase activity with k(cat)/KM values from 10(3) to 10(5) M(-1) s(-1). Glx2-1 can hydrolyze cephalosporins and carbapenems, albeit wit ...[more]

PMID: 19735113

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