Cryptic proteolytic activity of dihydrolipoamide dehydrogenase.
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ABSTRACT:
SUBMITTER: Babady NE
PROVIDER: S-EPMC1851069 | biostudies-literature | 2007 Apr
REPOSITORIES: biostudies-literature
Publications
Cryptic proteolytic activity of dihydrolipoamide dehydrogenase.
Babady Ngolela Esther NE Pang Yuan-Ping YP Elpeleg Orly O Isaya Grazia G
Proceedings of the National Academy of Sciences of the United States of America 20070402 15
The mitochondrial enzyme, dihydrolipoamide dehydrogenase (DLD), is essential for energy metabolism across eukaryotes. Here, conditions known to destabilize the DLD homodimer enabled the mouse, pig, or human enzyme to function as a protease. A catalytic dyad (S456-E431) buried at the homodimer interface was identified. Serine protease inhibitors and an S456A or an E431A point mutation abolished the proteolytic activity, whereas other point mutations at the homodimer interface domain enhanced the ...[more]
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