treA Codifies for a Trehalase with Involvement in Xanthomonas citri subsp citri Pathogenicity

Autor(es)

Alexandrino, Andre Vessoni ; Goto, Leandro Seiji ; Marques Novo-Mansur, Maria Teresa

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 11, n. 9 SEP 9 2016.
• Citações Web of Science: 2

Resumo

Citrus canker, caused by the bacterium Xanthomonas citri subsp. citri (Xcc), is a severe disease of citrus. Xcc presents broad spectrum of citrus hosts including economically important species whereas X. fuscans subsp. aurantifolii-type C (XauC) causes a milder disease and only infects Citrus aurantifolia. Trehalase catalyzes hydrolysis of the disaccharide trehalose, a sugar that has been reported to be related to Xcc pathogenicity. We expressed the recombinant gene product and assessed Xcc trehalase structural and kinetics data. The recombinant protein presented 42.7% of secondary structures in alpha-helix and 13% in beta-sheets, no quaternary structure in solution, and Michaelis-Menten constant (K-M) of 0.077 mM and V-max 55.308 mu Mol glucose.min(-1).mg protein(-1) for trehalose. A Xcc mutant strain (Xcc Delta treA) was produced by gene deletion from Xcc genome. Enzymatic activity of trehalase was determined in Xcc, XauC and Xcc Delta treA cellular lysates, showing the highest values for XauC in in vitro infective condition and no activity for Xcc Delta treA. Finally, leaves of Citrus aurantifolia infected with Xcc Delta treA showed much more drenching and necrosis than those infected by wild type Xcc. We concluded that trehalase contributes to alleviate bacterial virulence and that inability for trehalose hydrolysis may promote higher Xcc infectivity. (AU)

• Processo FAPESP: 07/50910-2 - Análise proteômica diferencial em Xanthomonas axonopodis: proteínas e genes de interesse biotecnológico
• Beneficiário: Maria Teresa Marques Novo Mansur
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores