EXG1p, a novel exo-β1,3-glucanase from the fungus Cochliobolus carbonum, contains a repeated motif present in other proteins that interact with polysaccharides

• Published in: Biochimica et biophysica acta. General subjects Vol. 1425; no. 3; pp. 632 - 636
• Main Authors: Nikolskaya, Anastasia N., Pitkin, John W., Schaeffer, Holly J., Ahn, Joong-Hoon, Walton, Jonathan D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 27.11.1998
• Subjects: Cell wall degrading enzyme; DNA sequence; Maize; Plant pathogen; β1,3-Glucanase; DNA sequence; β1,3-Glucanase; Maize; Cell wall degrading enzyme; Plant pathogen
• ISSN: 0304-4165; 1872-8006
• DOI: 10.1016/S0304-4165(98)00117-2

Genomic and cDNA copies of EXG1, a gene encoding an exo-β1,3-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-β1,3-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.