title: EXG1p, a novel exo-beta1,3-glucanase from the fungus Cochliobolus carbonum, contains a repeated motif present in other proteins that interact with polysaccharides.
abstract: Genomic and cDNA copies of EXG1, a gene encoding an exo-beta1, 3-glucanase from the plant pathogenic fungus Cochliobolus carbonum, were isolated. The gene contains two introns of 50 and 53 bp, and the mRNA has a 5'-untranslated region of 90 nt and a 3'-untranslated region of 159 nt. The deduced protein product, EXG1p, has a predicted signal peptide of 17 amino acids, but based on the known N-terminus of the mature protein is further processed to remove an additional 25 amino acids. The sequence of EXG1p is not closely related to any other known protein, but has a low similarity (29% overall amino acid identity) to BGN13.1, an endo-beta1,3-glucanase from the mycoparasitic fungus Trichoderma harzianum. EXG1p contains two imperfect copies of a 23-amino acid motif that is found in several other proteins that interact with polysaccharides, including plant and bacterial polygalacturonases, phage neck appendage protein, phage endoneuramidase, and bacterial mannuronan epimerase.
authors.affiliation: Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: A N
authors.initials: AN
authors.lastname: Nikolskaya
authors.forename: J W
authors.initials: JW
authors.lastname: Pitkin
authors.forename: H J
authors.initials: HJ
authors.lastname: Schaeffer
authors.forename: J H
authors.initials: JH
authors.lastname: Ahn
authors.forename: J D
authors.initials: JD
authors.lastname: Walton
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics*; D001483:Base Sequence; D018076:DNA, Complementary / Q000302:isolation & purification; D005800:Genes, Fungal; D043326:Glucan 1,3-beta-Glucosidase; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D016415:Sequence Alignment; D001617:beta-Glucosidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D011134:Polysaccharides; D012333:RNA, Messenger; D001617:beta-Glucosidase; D043326:Glucan 1,3-beta-Glucosidase