Mycosystema. 2007, 26(1): 97-105.
Laccase overproducing Trametes gallica strain SAH-12 was obtained from parent strain Trametes gallica by UV mutagenesis. Using RACE (rapid amplification of cDNA ends) method, a full-length cDNA of laccase gene and its corresponding genomic sequence, designated as Lacc1 (DQ431716) and Lac1 (DQ431715), were cloned from mutated strain SAH-12 of Trametes gallica, respectively. Sequencing analysis suggested that this gene belongs to fungi laccase gene family, and there are 98% homology in the nucleotide sequence and the deduced amino acid sequence of Lacc1 and the lacA gene from original strain T.gallica. The full length of Lacc1 was 1891bp,with 40,1554 and 297bp of 5' untranslated region,open reading frame (ORF) and 3'untranslated region,respectively.It contains polyadenylation signal AATACA and 59bp PolyA.The ORF of Lacc1 encode a polypeptide comprised of 517 amino acid residues,which included a signal peptide of 21 amino acid residues and a mature protein of 496 amino acid residues,which included a signal peptide of 21 amino acid residues and a mature protein of 496 amino acid residues.In the deduced amino acid sequence of Lacc1 gene,there are 4 putative N-glycosylation sites,4 Cys residues for forming disulfide bonds,and also 4 hihgly conserved amino acid sequences,which could combine with Ⅰ,Ⅱ and Ⅲ type copper.The full length of Lac1 gene was 2338bp,with 10 introns and 11 exons.Introns ranged in size from 51 to 76bp,and ist sequence complied with the rule of“5'-gt”and“ag-3'”.