International Commission for the Taxonomy of Fungi (ICTF)
International Union of Microbiological Societies (IUMS, Mycology Division)

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The clonal species Trichoderma parareesei sp. nov. likely resembles the ancestor of the cellulase producer Hypocrea jecorina/T. reesei.

Atanasova, L., Jaklitsch, W.M., Komoń-Zelazowska, M., Kubicek, C.P. and Druzhinina, I.S., 2010
Appl. Environ. Microbiol. 76(21):7259-67

We have previously reported that the prominent industrial enzymeproducer Trichoderma reesei (teleomorph Hypocrea jecorina; Hypocreales,Ascomycota, Dikarya) has a genetically isolated, sympatric sisterspecies devoid of sexual reproduction, a species, which is constitutedby the majority of anamorphic strains previously attributedto H. jecorina/T. reesei.

In this paper we present the formaltaxonomic description of this new species, T. parareesei, complementedby multivariate phenotype profiling and molecular evolutionaryexamination. A phylogenetic analysis of relatively conservedloci such as coding fragments of the RNA polymerase B subunitII (rpb2) and GH18 chitinase (chi18-5) showed that T. parareeseiis genetically invariable and likely resembles the ancestor,which gave raise to H. jecorina. This and the fact that at leastone mating type gene of T. parareesei has been previously foundto be essentially altered compared to H. jecorina/T. reesei,indicate that divergence probably occurred due to the impairedfunctionality of the mating system in the hypothetical ancestorof both species. In contrast, we show that the sexually reproducingand correspondingly more polymorphic H. jecorina/T. reesei isessentially evolutionarily derived. Phenotype microarray analysesperformed at seven temperature regimes support our previousspeculations that T. parareesei possesses a relatively highopportunistic potential, which probably assured the survivalof this species in ancient and sustainable environment suchas tropical forests.


Copyright: Irina Druzhinina & Alexey Kopchinskiy 2004 - 2008