Journal of Plant Pathology (2006) 88, p. S31 (Ambrosino et al.)

P. Ambrosino, E. Morán, M. Ruocco, R. Hermosa, E. Monte and M. Lorito (2006)
Isolation and sequencing of an endopolygalacturonase gene from two biocontrol strains of Trichoderma harzianum
Journal of Plant Pathology 88 (3, Special Issue), S31-S31
S.I.Pa.V XIII National Meeting - Foggia, 12-16 September 2006 - Poster
Abstract: Strains of Trichoderma spp. secrete proteins to penetrate fungal hosts and plant cell wall, and eventually induce ISR. Using a proteomic approach, we have analysed the secretome of the biocontrol Trichoderma harzianum strains T22 and T34, in order to identify differentially expressed proteins. 2DE maps of extracellular proteins were generated from culture filtrates obtained by growing Trichoderma in mycoparasitic, nutrient stress, or with a plant interaction conditions. Using MALDI-tof and MS/MS mass spectrometry and an Expressed Sequence Tag (EST) database of Trichoderma spp., we found one protein exhibiting a high degree of similarity to an endo-polygalacturonase (PG). The corresponding gene from both strains was cloned and sequenced, thus obtaining the first endo-PG nt sequence of T. harzianum. Thpg1 from strain T34 consists of an ORF of 1156 bp, which encodes a polypeptide of 380 aminoacids with a molecular weight of 38.3 kDa and a calculated pI of 5.5. Sequence analysis by BlastX program indicated a high homology with a hypothetical protein of Aspergillus nidulans (e-135) and a PG of Ophiostoma novo-ulmi (e-126). Gene expression in different growth conditions was analysed (i.e. in the presence of glucose, chitin, fungal cell walls, plant cell walls, nitrogen starvation, pectin) by collecting the mRNAs at 4, 8, and 24 h after culture start. High level of expression was detected in the presence of 0.1% pectin and 1% strawberry or fungal cell walls (Rhizoctonia solani and Pythium ultimum). Over-expression in Arabidopsis of the corresponding PG gene of the T. harzianum is being done.
Database assignments for author(s): Michelina Ruocco, Enrique Monte

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
molecular biology - genes

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Trichoderma harzianum (antagonist)