Analysis of an endopolygalacturonase enzyme and its coding gene (pg1) from the potato pathogen Rhizoctonia solani AG-3.

MACHINANDIARENA,M.; PATIÑO, B.; VÁZQUEZ, C.; SALGADO, M. R.; DALEO,G. R.; GONZÁLEZ-JAÉN, M. T.

Vienna University of Technology. Vienna, Austria.

Conferencia; 8th European Conference on Fungal Genetics.; 2006

Rhizoctonia canker is caused by the fungus Rhizoctonia solani. There are a number of strains of this fungus, called anastomosis groups (AG) that affect a wide range of crops. It has been found that AG-3 of R. solani is the major cause of the Rhizoctonia disease in potato crops. Rhizoctonia canker is present in all potato growing areas of the world. Symptoms and signs of Rhizoctonia canker include cankers on stems, sprouts and stolons, malformation of tubers and sclerotia formed on the surface of mature tubers. Endopolygalacturonases (endoPGs) are plant cell wall-degrading enzymes that have been implicated in the invasion of plant tissue by pathogenic microbes. EndoPGs have been described from bacteria, plants, insects and numerous species of phytopathogenic fungi. In this work, we report the purification and characterization of an extracellular endopolygalacturonase (PG1) produced by R. solani AG3 and its coding gene (pg1), which was analyzed and compared with other endopolygalacturonase genes. The expression of this gene was induced by pectin, polygalacturonic acid and glucose in in vitro cultures. Pg1 gene was highly expressed in planta assays suggesting that this endopolygalacturonase might be actively involved during infection process.