Generation and Characterization of Fumarase C Mutants
نویسنده
چکیده
Fumarase C is responsible for the reversible hydration/dehydration of S-malate to fumarate during the catabolic Kreb’s cycle. Using PCR based site-directed mutagenesis; two active site mutants of fumarase C have been constructed. The recombinant enzymes, S139A and S140A, were purified using metal affinity chromatography and subjected to kinetic analysis and X-ray crystallization. The kinetic investigations indicate that serine 140 may play a role in the reversible conversion of S-malate to fumarate. Overall, this investigation aims to map the roles of serine 139 and 140 within the fumarase C active site.
منابع مشابه
Oxygen- and growth rate-dependent regulation of Escherichia coli fumarase (FumA, FumB, and FumC) activity.
Escherichia coli contains three biochemically distinct fumarases which catalyze the interconversion of fumarate to L-malate in the tricarboxylic acid cycle. Batch culture studies indicated that fumarase activities varied according to carbon substrate and cell doubling time. Growth rate control of fumarase activities in the wild type and mutants was demonstrated in continuous culture; FumA and F...
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