(A) Germination of QM6a conidia on a PDA plate. (B) Two single-ascospore cultures of T. reesei env1 mutant were inoculated on a 10-cm MEA plate under a 12-hour light and 12-hour dark photoperiod. (C) T. reesei fruiting bodies and droplets of liquid forming on their surface (D) T. reesei linear asci and each asci contains 16 ascospores. Credits: Wan-Chen Li, Chia-Ling Chen, Yu-Chien Chuang and Ting-Fang Wang. Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.

Trichoderma reesei QM6a (ATCC 13631), the ancestor of all currently used cellulase-producing mutant, was the first T. reesei genome completed sequenced. The DOE is funding research into developing T. reesei as a host to produce low cost enzymes for the conversion of plant biomass materials into industrially useful bioproducts such as sugars and bioethanol. As a system for studying genomics, T. reesei with its genome size of 34,922,528 bp and seven chromosomes has many advantages: EST and cDNA collections, BAC libraries available to academic researchers from the Fungal Genomics Laboratory at NCSU, DNA mediated transformation is a routine procedure, gene knockout protocols have been developed and there is an active academic community of researchers world-wide. QM6a is the anamorph of Hypocrea jecorina CBS999.97. T. reesei undergoes a heterothallic reproductive cycle and generates fruiting bodies (stromata) containing linear asci with 16 ascospores. The sexual crossing approach opens up perspectives for biotechnologically important fungi. Sexual crossing readily induced cytosine-to-thymine point mutations on both tandem and unlinked duplicated sequences. T. reesei has evolved a robust repeat-induced point mutation (RIP) system. The QM6a genome contains 2329 interspersed AT-rich blocks.