Ivanova, P.M., Harizanova, N.T., Krasteva, M., Dimov, S.G., Ralchev, K.H. (2004). Drosophila dihydrolipoamide dehydrogenase. protein structure. developmental expression.  Ann. Univ. Sof. St. Klim. Ohrid. 96(4): 115--123.

FBrf0257612

Research paper

Dihydrolipoamide dehydrogenase (DLD) is the common flavoprotein component (E3) of three multienzyme a-ketoacid dehydrogenase complexes (pyruvate dehydrogenase, α-ketoglutarate dehydrogenase and branched-chain α-ketoacid dehydrogenase complexes) where it catalyzes the NAD+ dependent oxidation of dihydrolipoamide covalently bound to the acetyltransferase component. DLD also catalyzes other NADH-dependent reactions and additional cellular functions for this enzyme have been suggested. We have previously reported the purification and partial characterization of a NADH diaphorase from D. melanogaster and D. virilis [1] with properties resembling those of DLD. N-terminal sequencing of the first 15 amino acid of the purified D. virilis protein revealed a high homology to DLD sequences. In addition, the partial sequences of 19 peptides obtained from the purified D. virilis protein. Several D. melanogaster cDNAs encoding DLD polypeptides containing an exact match to the D. virilis N-terminal sequence were located in the collection of expressed sequence tags of the Berkeley Drosophila Genome Project. One of these cDNAs was completely sequenced, and matches to the partial D. virilis peptide sequences were located in the deduced protein sequence. The deduced protein shows high similarity to DLDs from other organisms. The expression of DLD throughout the life cycle of D. melanogaster was determined by using the cDNA as a probe for northern blots, polyclonal antibodies on western blots and staining for diaphorase activity after electrophoresis on native gels.