Expression of a Butyrivibrio fibrisolvens E14 gene (cinB) encoding an enzyme with cinnamoyl ester hydrolase activity is negatively regulated by the product of an adjacent gene (cinR)

Abstract

A second cinnamoyl ester hydrolase (CEH) encoding gene (cinB) has been characterized from the ruminal bacterium Butyrivibrio fibrisolvens E14. CinB is more similar to CinA (previously named Cinl) (28% amino acid identity), the first CEH described from B. fibrisolvens E14, than either of the enzymes are to any other member of the family of hydrolases to which they belong. Upstream of cinB, and in the opposite orientation, is a gene (cinR) encoding a protein with substantial similarity to members of the MarR family of negative regulators of bacterial gene expression. By alignment of these sequences, a possible helix-turn-helix DNA-binding domain has been identified. CinR was expressed at a high level in Escherichia coli using the lac promoter. In E. coli CinR repressed the expression of CinB, but had no effect on the expression of CinA. In gel mobility-shift assays, CinR bound specifically to the cinR-cinB intergenic region. Two identical 16 nucleotide inverted repeats adjacent to the putative PcinR and PcinB promoters are likely binding sites for CinR. The addition of FAXX (O-[5-O-(trans-feruloyl)-α-L-arabinofuranosyl]-(1,3)-O-ß-D-xylopyranosyl-(1,4)-D-xylopyranose) and Fara [5-O-(trans-feruloyl)-arabinofuranose], but not xylobiose, ferulic acid and a number of other soluble components of hemicellulose, inhibited the binding of CinR to DNA.

Anaerobic p -Coumarate Degradation by Rhodopseudomonas palustris and Identification of CouR, a MarR Repressor Protein That Binds p -Coumaroyl Coenzyme A

“…The DNA-binding domains of MarR proteins have a characteristic winged helix-turn-helix fold, and most MarR proteins bind to inverted repeats in the Ϫ35 or Ϫ10 region of the operons they control (43). MarR family proteins were first characterized as regulators of antibiotic resistance and oxidative stress responses in E. coli and Salmonella (22,37), but many are now known to be reg- ulators of aromatic compound catabolism (4,5,7,8,32,45). CouR binds to a 30-bp region encompassing an inverted repeat separated by a 3-bp spacer that overlaps the Ϫ10 promoter element (Fig.…”

Biodegradation of Aromatic Compounds by Escherichia coli

“…1A). The 148-aa HpaR (HpcR) protein has significant identity to members of the MarR family of bacterial regulatory proteins involved in the metabolism of aromatic compounds, such as the CinR repressor (30% identity) from Butyrivibrio fibrisolvens, which responds to cinnamoyl esters (61), and the BadR activator (27% identity) from Rhodopseudomonas palustris, which most probably responds to benzoyl-CoA (84). The HTH motif associated with the MarR family (3) is also present in the central region of the HpaR (HpcR) regulator.…”

Thermostable feruloyl esterase for the bioproduction of ferulic acid from triticale bran

“…On the bacterial side, even fewer clones are available. These are limited to Cellvibrio japonicum (DeBoy et al 2008; formerly Pseudomonas fluorescens; Ferreira et al 1993), Burkholderia multivorans (Rashamuse et al 2007), Butyrivibrio fibrisolvens (Dalrymple et al 1996;Dalrymple and Swadling 1997), Pseudoalteromonas halosplanktis (Aurilia et al 2008), Clostridium thermocellum cellulosome (Blum et al 2000), and Prevotella ruminicola (Dodd et al 2009). …”