tailieunhanh - Báo cáo khoa học: A complete survey of Trichoderma chitinases reveals three distinct subgroups of family 18 chitinases

Genome-wide analysis of chitinase genes in theHypocrea jecorina(ana-morph:Trichoderma reesei) genome database revealed the presence of 18 ORFs encoding putative chitinases, all of them belonging to glycoside hydrolase family 18. Eleven of these encode yet undescribed chitinases. A sys-tematic nomenclature for theH. | ềFEBS Journal A complete survey of Trichoderma chitinases reveals three distinct subgroups of family 18 chitinases Verena Seidl Birgit Huemer Bernhard Seiboth and Christian P. Kubicek Research Area Gene Technology and Applied Biochemistry Institute of ChemicalEngineering TU Vienna Austria Keywords chitinase glycoside family 18 killer toxin mycoparasitism Trichoderma Correspondence V. Seidl Research Area Gene Technology and Applied Biochemistry Institute of Chemical Engineering TU Vienna Getreidemarkt 9-166-5 A-1060 Vienna Austria Fax 43 1 58801 17299 Tel 43 1 58801 17263 E-mail vseidl@ Website http Received 5 August 2005 revised 8 September 2005 accepted 26 September 2005 doi Genome-wide analysis of chitinase genes in the Hypocrea jecorina ana-morph Trichoderma reesei genome database revealed the presence of 18 ORFs encoding putative chitinases all of them belonging to glycoside hydrolase family 18. Eleven of these encode yet undescribed chitinases. A systematic nomenclature for the H. jecorina chitinases is proposed which designates the chitinases corresponding to their glycoside hydrolase family and numbers the isoenzymes according to their pI from Chi18-1 to Chi18-18. Phylogenetic analysis of H. jecorina chitinases and those from other filamentous fungi including hypothetical proteins of annotated fungal genome databases showed that the fungal chitinases can be divided into three groups groups A and B corresponding to class V and III chitinases respectively also contained the so Trichoderma chitinases identified to date whereas a novel group C comprises high molecular weight chitinases that have a domain structure similar to Kluyveromyces lactis killer toxins. Five chitinase genes representing members of groups A-C were cloned from the myco-parasitic species H. atroviridis anamorph T. atroviride . Transcription of chi18-10 belonging to group C and chi18-13 belonging to a novel clade in .