title: Isolation and characterization of a fruiting body-specific exo-beta-1,3-glucanase-encoding gene, exg1, from Lentinula edodes.
abstract: An exo-beta-1,3-glucanase-encoding gene was isolated from Lentinula edodes to investigate the relationship between the cell wall lytic enzyme and mushroom morphogenesis. The deduced amino acid sequence of the protein corresponding to the exg1 gene displayed 67% identity to AbEXG1 of Agaricus bisporus and approximately 40% identity to yeast exo-beta-1,3-glucanases. Two conserved glutamic acids within the catalytic active site in yeast exo-beta-1,3-glucanases were conserved in exg1 of L. edodes. The exg1 gene was expressed in fruiting bodies, but not in vegetative mycelia. Expression was higher in the stipe than in the pileus of young fruiting bodies. The gene was additionally expressed in the gills of mature fruiting bodies. We purified a glucanase from the stipes of young fruiting bodies that had an N-terminus identical to that of the putative exg1 product. These results collectively indicate that exg1 is involved in L. edodes fruiting body development, including stipe elongation.
authors.affiliation: Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami-shi, Iwate 024-0003, Japan. sakamoto@ibrc.or.jp
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Sakamoto
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Irie
authors.forename: Toshitsugu
authors.initials: T
authors.lastname: Sato
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D017931:DNA Primers; D005800:Genes, Fungal; D043326:Glucan 1,3-beta-Glucosidase / Q000235:genetics* / Q000302:isolation & purification; D007700:Kinetics; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D020942:Shiitake Mushrooms / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D017931:DNA Primers; D011994:Recombinant Proteins; D043326:Glucan 1,3-beta-Glucosidase
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