3-hydroxy-3-phenylpropionyl-CoA dehydrogenase (BbsC)

3-hydroxy-3-phenylpropionyl-CoA dehydrogenase, also referred to as phenylhydroxypropionyl-CoA dehydrogenase, is a specialized enzyme primarily identified in plant-associated and anaerobic soil bacteria (Meyer et al., 2018; UniProt Q9KJF2). It plays a pivotal role in the beta-oxidation of aromatic compounds by catalyzing the NAD+-dependent oxidation of 3-hydroxy-3-phenylpropionyl-CoA or its derivatives, such as those produced during ferulic acid degradation, to their corresponding 3-keto (beta-keto) forms. In Agrobacterium fabrum, the enzyme is encoded by the atu1415 gene and is essential for the catabolism of plant-derived hydroxycinnamic acids, a process that facilitates both bacterial nutrition and the detoxification of inhibitory plant phenolics (Meyer et al., 2014; ASM Journals). This metabolic activity is a key determinant in the ecological transition of Agrobacterium from a commensal rhizospheric inhabitant to a virulent pathogen capable of inducing crown-gall tumors in host plants (Meyer et al., 2020; Oxford Academic). Additionally, in anaerobic toluene-degrading bacteria like Thauera aromatica, the enzyme (often termed BbsC as part of the BbsCD complex) is vital for the processing of benzylsuccinate intermediates (Heider et al., 2016; Semantic Scholar). While there are currently no approved clinical drugs targeting this enzyme, it represents a significant target for the development of anti-virulence strategies in agriculture and a valuable biocatalyst in the metabolic engineering of value-added aromatic chemicals such as vanillin.

Other names

Phenylhydroxypropionyl-CoA dehydrogenaseAtu14154-hydroxy-3-methoxyphenyl-beta-hydroxypropionyl-CoA dehydrogenase2-(alpha-hydroxybenzyl)succinyl-CoA dehydrogenaseBbsCD complex subunit C

The enzyme catalyzes the NAD+-dependent oxidation of a 3-hydroxy-phenylpropionyl-CoA ester (or related hydroxycinnamic acid derivatives such as 4-hydroxy-3-methoxyphenyl-beta-hydroxypropionyl-CoA) to its corresponding 3-ketoacyl-CoA (beta-keto) form, which is subsequently cleaved by a thiolase in a beta-oxidation-like pathway.