This entry represents the FmdE protein that is encode by the molybdenum formylmethanofuran dehydrogenase operon. FmdE does not co-purify with the molybdenum isozyme that is formed by FmdC and FmdB [1]. The domain is typically found as a single copy, but is repeated in some sequence two to three times. It is also common place to find this domain co-occurs with a zinc-beta ribbon domain, suggesting that is may bind nucleic acid and be involved in transcription regulation.

1: The molybdenum formylmethanofuran dehydrogenase operon and the tungsten formylmethanofuran dehydrogenase operon from Methanobacterium thermoautotrophicum. Structures and transcriptional regulation. Hochheimer A, Linder D, Thauer RK, Hedderich R; Eur J Biochem. 1996;242:156-162. PMID:8954165