The oxidizing enzyme laccase produced by many fungi is generally considered to be active in the biodegradation of lignin, a major plant cell wall component highly resistant to microbial attack. Using degenerate primers and molecular techniques such as genome-walking and RT-PCR, a laccase gene and its corresponding cDNA were cloned from Ganoderma lucidum. The coding region of the genomic laccase sequence, which is preceded by the eukaryotic promoter elements TATA and CAAT, spans more than 2107 bp. The corresponding laccase cDNA was identical to the genomic sequence except for 9 introns that were 51-78 bp long. Sequence analysis indicated that the G. lucidum lccGl product has 10 potential N-glycosylation sites (Asn-Xxx-Ser/Thr) and four conserved fungi laccase amino acids signature sequences. The G. lucidum laccase sequence is most similar to the sequence of the laccase from Flammulina velutipes (similarity 73%).
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