Identification of a Histidine Metal Ligand in the argE-Encoded N-Acetyl-L-Ornithine Deacetylase from Escherichia coli.
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ABSTRACT:
SUBMITTER: McGregor WC
PROVIDER: S-EPMC4320195 | biostudies-literature | 2013
REPOSITORIES: biostudies-literature
Publications
Identification of a Histidine Metal Ligand in the argE-Encoded N-Acetyl-L-Ornithine Deacetylase from Escherichia coli.
McGregor Wade C WC Gillner Danuta M DM Swierczek Sabina I SI Liu Dali D Holz Richard C RC
SpringerPlus 20130923
The H355A, H355K, H80A, and H80K mutant enzymes of the argE-encoded N-acetyl-L-ornithine deacetylase (ArgE) from Escherichia coli were prepared, however, only the H355A enzyme was found to be soluble. Kinetic analysis of the Co(II)-loaded H355A exhibited activity levels that were 380-fold less than Co(II)-loaded WT ArgE. Electronic absorption spectra of Co(II)-loaded H355A-ArgE indicate that the bound Co(II) ion resides in a distorted, five-coordinate environment and Isothermal Titration Calorim ...[more]
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