title: Differential esterase expression in leaves of Manihot esculenta Crantz infected with Xanthomonas axonopodis pv. manihotis.
abstract: The polyacrylamide gel electrophoresis system (PAGE) and inhibition tests for biochemical characterization of alpha- and beta-esterases were used to obtain a functional classification of esterases in plants and to show a differential expression of esterases as markers of pathogenesis in cassava plants (Manihot esculenta Crantz). The characterization of alpha- and beta-esterases from leaves of M. esculenta by the PAGE system was possible using an extraction solution containing two phenol-complexing agents (PVP-40 and sodium metabisulfite), three antioxidant agents (EDTA, beta-mercaptoethanol, and DTT), and one quinone reducer (ascorbic acid). Fourteen esterase isozymes were detected in young unexpanded leaves of M. esculenta cultivars. The inhibition pattern of alpha- and beta-esterases of M. esculenta showed that Est-9 is an arylesterase, and in the unexpanded leaves of the M. esculenta plants infected with Xanthomonas axonopodis pv. manihotis, the Est-7 beta-esterase showed the characteristic staining of an alpha/beta-esterase. This diffrential expression of Est-7 isozyme in young unexpanded leaves of cassava plants can be used as a marker of pathogenesis after infection with X. axonopodis pv. manihotis.
authors.affiliation: Department of Cell Biology and Genetics, State University of Maringá, Parana, Brazil.
authors.forename: A J
authors.initials: AJ
authors.lastname: Pereira
authors.forename: A S
authors.initials: AS
authors.lastname: Lapenta
authors.forename: P S
authors.initials: PS
authors.lastname: Vidigal-Filho
authors.forename: M F
authors.initials: MF
authors.lastname: Machado
mesh_terms: D004591:Electrophoresis, Polyacrylamide Gel; D004950:Esterases / Q000302:isolation & purification / Q000378:metabolism*; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism; D002365:Manihot / Q000201:enzymology* / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology; D018515:Plant Leaves / Q000201:enzymology; D014974:Xanthomonas / Q000472:pathogenicity*
chemical_list: D007527:Isoenzymes; D004950:Esterases