title: Identification of B6T173 (ZmPrx35) as the prevailing peroxidase in highly insect-resistant maize (Zea mays, p84C3) kernels by activity-directed purification.
abstract: Plant peroxidases (PODs) are involved in diverse physiological processes, including defense against pathogens and insects. Contrary to their biological importance, only very few plant PODs have been proven on protein level, because their low abundance makes them difficult to detect in standard proteomics work-flows. A statistically significant positive correlation between POD activity and post-harvest insect resistance has been found for maize (Zea mays, p84C3) kernels. In combining activity-directed protein purification, genomic and proteomic tools we found that protein B6T173 (ZmPrx35) is responsible for the majority of the POD activity of the kernel. We successfully produced recombinant ZmPrx35 protein in Escherichia coli and demonstrate both, in vitro activity and the presence of a haem (heme) cofactor of the enzyme. Our findings support the screening for insect resistant maize variants and the construction of genetically optimized maize plants.
authors.affiliation: Laboratory of Biochemical and Instrumental Analysis, Department of Biotechnology and Biochemistry, Cinvestav Unidad Irapuato Irapuato, Mexico ; Laboratorio Nacional de Genómica para la Biodiversidad, Unidad de Genómica Avanzada del Centro de Investigación y de Estudios Avanzados - Instituto Politécnico Nacional Irapuato, Mexico.
authors.forename: Laura M
authors.initials: LM
authors.lastname: López-Castillo
authors.affiliation: Laboratory of Biochemical and Instrumental Analysis, Department of Biotechnology and Biochemistry, Cinvestav Unidad Irapuato Irapuato, Mexico.
authors.forename: Janet A I
authors.initials: JA
authors.lastname: López-Arciniega
authors.affiliation: Department of Biotechnology and Biochemistry, Cinvestav Unidad Irapuato Irapuato, Mexico.
authors.forename: Armando
authors.initials: A
authors.lastname: Guerrero-Rangel
authors.affiliation: Department of Biotechnology and Biochemistry, Cinvestav Unidad Irapuato Irapuato, Mexico.
authors.forename: Silvia
authors.initials: S
authors.lastname: Valdés-Rodríguez
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Unidad de Genómica Avanzada del Centro de Investigación y de Estudios Avanzados - Instituto Politécnico Nacional Irapuato, Mexico.
authors.forename: Luis G
authors.initials: LG
authors.lastname: Brieba
authors.affiliation: Plant-Food Molecular Breeding Unit, Tecnologico de Monterrey Monterrey, Mexico.
authors.forename: Silverio
authors.initials: S
authors.lastname: García-Lara
authors.affiliation: Laboratory of Biochemical and Instrumental Analysis, Department of Biotechnology and Biochemistry, Cinvestav Unidad Irapuato Irapuato, Mexico.
authors.forename: Robert
authors.initials: R
authors.lastname: Winkler
keywords: activity-directed proteomics; insect resistance; low-abundance proteins; maize (Zea mays); peroxidase; plant proteomics