CLONING AND SEQUENCE-ANALYSIS OF 2 LACCASE COMPLEMENTARY DNAS FROM THE LIGNINOLYTIC BASIDIOMYCETE TRAMETES-VERSICOLOR

Laccases are oxidoreductase enzymes involved in the oxidation of vario us phenolic compounds. They may play a role in the biodegradation of l ignin and in the dechlorination of chlorophenols. The cDNAs encoding l accase LccI and a putative laccase LccIV and the gene for LccI from th e white-rot basidiomycete Trametes versicolor were cloned, sequenced a nd characterized. The genomic DNA of lccI consists of 2128 bp, with th e coding region interrupted by 10 introns; the cDNA consists of a 1560 bp open reading frame (ORF). The cDNA of the putative lccIV gene cons ists of a 1581 bp ORF, with a 794 bp 5' untranslated region. The size of the major transcript for both lccI and lccIV is approximately 2.3 k b. Transcription of lccIV was induced by 2,5-dimethylaniline, whereas the opposite effect was observed for lccI. Laccases I and IV contain h ighly conserved histidinyl and cysteinyl residues, believed to be invo lved in binding copper, and share extensive sequence similarity with o ther laccases produced by both ligninolytic and non-ligninolytic fungi . (C) 1997 Elsevier Science B.V.