Protein
Bifunctional ligase/repressor BirA
Organism
Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd)
Function
Acts both as a biotin--[acetyl-CoA-carboxylase] ligase and a biotin-operon repressor. In the presence of ATP, BirA activates biotin to form the BirA-biotinyl-5'-adenylate (BirA-bio-5'-AMP or holoBirA) complex. HoloBirA can either transfer the biotinyl moiety to the biotin carboxyl carrier protein (BCCP) subunit of acetyl-CoA carboxylase, or bind to the biotin operator site and inhibit transcription of the operon.
Similarity
Belongs to the biotin--protein ligase family.
Sequence
MMNFTLLTYLADCQPKVRSELEKFSKNLEEDIQQLREIGLDILVDGQDYRLVPMLPLLNPQQISTALFPYSIHYQPIISSTNEWILQNILSLKKGDLCVAEYQTAGRGRRGRQWLSPFAGQIMFSFYWAFDPKKSIEGLSLVIGLAIAEVLNVQVKWPNDILFDERKLGGILVEIANHKNGMLNLVIGIGINVSLSKQTEISQPYAEVCEIDPDVERQTLLPKLIQHLYTRLNIFEQNGIDEEFQQAWQSYNAFSNSEINVLTEQGVISGIEQGIDERGYLKVLCGNKIQMFNGGEVSLRKK