Discovery, biocatalytic exploration and structural analysis of a 4-ethylphenol oxidase from Gulosibacter chungangensis

Alvigini Laura, Alejandro Gran-Scheuch, Yiming Guo, Milos Trajkovic, Mohammad Saifuddin, Marco W Fraaije, Andrea Mattevi*

*Bijbehorende auteur voor dit werk

OnderzoeksoutputAcademicpeer review


The vanillyl-alcohol oxidase (VAO) family is a rich source of biocatalysts for the oxidative bioconversion of phenolic compounds. Through genome mining and sequence comparisons, we found that several family members lack a generally conserved catalytic aspartate. This finding led us to study a VAO-homolog featuring a glutamate residue in place of the common aspartate. This 4-ethylphenol oxidase from Gulosibacter chungangensis (Gc4EO) shares 42% sequence identity with VAO, contains the same 8α-N3-histidyl-bound FAD and uses oxygen as electron acceptor. However, Gc4EO features a distinct substrate scope and product specificity as it is primarily effective in the dehydrogenation of para -substituted phenols with little generation of hydroxylated products. The three-dimensional structure shows that the characteristic glutamate side chain creates a closely packed environment that may limit water accessibility and thereby protect from hydroxylation. With its high thermal stability, well defined structural properties and high expression yields, Gc4EO may become a catalyst of choice for the specific dehydrogenation of phenolic compounds bearing small substituents.

Originele taal-2English
Aantal pagina's10
Vroegere onlinedatum15-sep-2021
StatusPublished - okt-2021

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