Structural characterization of PthA effector protein from Xanthomonas axonopodis pv. citri, the causal agent of citrus canker

• Grant number: 08/10555-1
• Support type: Scholarships in Brazil - Doctorate (Direct)
• Effective date (Start): March 01, 2009
• Effective date (End): August 31, 2013
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal researcher: Mário Tyago Murakami
• Grantee: Joice Helena Paiva
• Home Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia, Inovações e Comunicações (Brasil). Campinas , SP, Brazil

Abstract

The citrus canker stands out as one of the main diseases of national and global citrus due to the easy dissemination and to affect all the commercial varieties of citrus. Caused by Xanthomonas axonopodis pv. citri (Xac), the citrus canker is characterized by the formation of water-soaked eruptions and pustule-like lesions on the surface of leaves, stems and fruits. During the infection, the bacteria reproduce in the intercellular space promoting division and differentiation of host cells. The molecular mechanism by which Xac induces hypertrophy and hyperplasia in the plant is not entirely clear, however it is known that the PthA effector protein display an important role in the physiopathology of the disease. The PthA, pathogen effector protein, functions as a transcription factor in the host cell and its structural assembly is formed by three main domains. In particular, its central region consisting of 34-amino acid repeats seems to be responsible for the interaction with target sites in the host DNA. In addition, PthA must probably bind to citrus proteins for trans-activation of genes related with cellular division and expansion. Until to date, it is not known any structure of a PthA/AvrBS3 protein family, which is of fundamental importance for the understanding of its function and mode of interaction with host proteins and DNA targets. Thus, this work aimed to obtain structural data of full-length PthA and/or its functional domains separately, using X-ray crystallography and other biophysical tools as small angle X-ray scattering. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

PAIVA, Joice Helena. Structure, function and stability of the glycosyl hidrolases that belong to GH5 family with potencial application in the conversion of lignocellulosic biomass in fermentable sugars. 2013. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia.