Short-chain fatty acyl coenzyme A regulator, C-terminal
This entry includes short-chain fatty acid regulators such as RAMB (regulator of acetate metabolism B), PCCR (Propionyl-CoA carboxylase regulator), PrpR (Propionate regulator). RamB is a negative transcriptional regulator of genes involved in acetate ...
This entry includes short-chain fatty acid regulators such as RAMB (regulator of acetate metabolism B), PCCR (Propionyl-CoA carboxylase regulator), PrpR (Propionate regulator). RamB is a negative transcriptional regulator of genes involved in acetate metabolism of C. glutamicum. It is responsible for expression control of the AK, PTA, ICL, and MS genes and, thus, for the proper adaptation to acetate as carbon and energy source. Nucleotide sequence analysis indicate the RamB protein consists of 469 aa with a putative HTH motif at the N terminus [1]. PCCR prevents the accumulation of propionyl-CoA by controlling expression of the gene encoding propionyl-CoA carboxylase, which is responsible for propionyl-CoA consumption by Rhodobacter sphaeroides. Many other Proteobacteria and Actinomycetales contain one or several PccR homologs that group into distinct clades on the basis of the pathway of acyl-CoA metabolism that they control [2]. PrpR is a transcriptional activator controlling prpDBC2 operon which encodes enzymes 2-methylcitrate dehydratase (PrpD2), 2-methylisocitrate lyase (PrpB2) and 2-methylcitrate synthase (PrpC2). They are essential for growth with propionate as carbon source. The regulatory protein belongs to the HTH_XRE regulator family. It has a length of 441 amino acids and an N-terminal lamda repressor-like DNA-binding domain [3]. This is the C-terminal domain, which is likely an iron sensor domain that adopts a GAF-like fold [4].
