Identification of two laccase genes in the cultivated mushroom Agaricus bisporus

Abstract

A cDNA library was constructed in I g t l l using mRNA from ll-d-old mycelium of Agaricus bisporus. Three clones containing laccase sequence were identified using an affinity-purified anti-laccase antibody. From one of these clones, a 333 bp sequence was used to identify further cDNA clones (including one which is close to full length) and a genomic clone. The coding sequences found were of two similar but not identical versions with differences at 36 out of 520 residues of deduced amino acid sequence. The laccase genes each encode a sequence expressed as a 2-3 kb mRNA, specifying a 520 residue polypeptide including a 19 amino acid residue signal peptide that is absent from the N terminus of the mature (extracellular) protein. The coding sequence of Zccl is interrupted by 14 short introns. The Zccl and Zcc2 genes are not allelic as they do not segregate in uninucleate spores derived from a four-spored basidium. Comparison of the deduced amino acid sequences with that of the other fungal laccases that have been cloned, and with the very similar ascorbate oxidases from higher plants shows that whilst some sequence is absolutely conserved at and around the amino acid residues involved in copper binding, the overall sequence similarities are low.

Characterization of a multicopper oxidase gene cluster in Phanerochaete chrysosporium and evidence of altered splicing of the mco transcripts

“…Recent genome analysis has revealed additional clustering among P-450, MnP and copper radical oxidase genes (Martinez et al, 2004). Families of structurally related genes have also been found in Pleurotus sajor-caju (Soden & Dobson, 2001), the basidiomycete CECT 20197 (Mansur et al, 1997), Pleurotus ostreatus (Palmieri et al, 2000), Trametes villosa (Yaver & Golightly, 1996), Agaricus bisporus (Perry et al, 1993) and Rhizoctonia solani (Wahleithner et al, 1995).…”

Heterologous expression of laccase cDNA from Ceriporiopsis subvermispora yields copper-activated apoprotein and complex isoform patterns

“…Laccase isoenzyme multiplicity is a phenomenon observed in several fungi, and in the case of Pleurotus sajor-caju (Soden & Dobson, 2001), the basidiomycete CECT 20197 (Mansur et al, 1997), Pleurotus ostreatus (Palmieri et al, 2000), Trametes villosa , Agaricus bisporus (Perry et al, 1993) and Rhizoctonia solani (Wahleithmer et al, 1995), families of structurally related genes have been described. In the case of C. subvermispora, over four isoforms are observed, with different substrate specificity, but only one gene, lcs-1, has been identified Salas et al, 1995).…”

Laccases and Their Applications: A Patent Review

“…These included laccases from A. nidulans [99], Coriolus hirsutus [60,62], Phlebia radiata [100], Agaricus bisporus [101], P. cinnabarinus [102], Coriolus versicolor [103], T. versicolor [72], Podospora anserina [104], Coprinus congregatus [105], Ganoderma lucidum, Phlebia brevispora, Lentinula edodes and Lentinus tigrinus Place for Table 2 [ 42,106]. Since then, the number of laccase genes sequenced has increased considerably, and searches from protein and gene sequence databases currently yield several hundreds of laccase gene sequences.…”