Characterization of a laccase gene from the white-rot fungus Trametes versicolor and structural features of basidiomycete laccases

• A gene coding for the multi-copper phenol oxidase laccase has been isolated from the white-rot basidiomycete Trametes oersicolor. The gene, which is preceded by a TATA box and a pyrimidine-rich region, is predicted to contain ten introns. The mature translation product, preceded by a 22-residue signal peptide, should consist of 498 residues. Comparisons with Edman degradation data of peptides from T. versicolor laccase strongly suggest that two disulfide bridges are formed by Cys-85/Cys-487 and Cys-117/Cys-205, respectively. The encoded protein contains five Cys, and the sequence surrounding the remaining Cys-452 is consistent with its involvement in the ligation of type-1 copper. Alignment of sequences indicates that T. versicolor laccase displays a Phe at the position corresponding to a residue (Met in ascorbate oxidase and azurin) considered important for the reduction potential of type-1 copper proteins.

Subject headings

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Keyword

Laccase

Phenol oxidase

Multi-copper enzyme

White-rot fungus

Lignin degradation

(T. versicolor)

Publication and Content Type

art (subject category)

ref (subject category)