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(Reference retrieved automatically from Google Scholar through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Characterization of an extracellular endopolygalacturonase from the saprobe Mucor ramosissimus Samutsevitsch and its action as trigger of defensive response in tropical plants

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Author(s):
Marques‚ M.R. ; Buckeridge‚ M.S. ; Braga‚ M.R. ; Dietrich‚ S.M.C.
Total Authors: 4
Document type: Journal article
Source: Mycopathologia; v. 162, n. 5, p. 337-346, 2006.
Abstract

In recent years, interest in the ability of non-pathogenic microorganisms to induce resistance in plants has grown, particularly with respect to their use as environmentally safe controllers of plant disease. In this study, we investigated the capacity of Mucor ramosissimus Samutsevitsch to release pectinases able to degrade cell walls of Palicourea marcgravii St. Hil., a tropical forest native Rubiaceae on which the spores of this saprobic fungus have been found. The fungus was grown in liquid culture medium containing pectin as the sole carbon source and filtrates were analyzed for pectinase activity. An endopolygalacturonase was partially purified by ion exchange chromatography, gel filtration, and preparative isoelectrofocusing, and characterized. This enzyme was more active upon pectic substrates with a low degree of methyl esterification. The products of hydrolysis of different pectic substrates (including pectin from P. marcgravii) by the action of this endopolygalacturonase elicited to different extents the phytoalexin production in soybean cotyledons. Also, the enzyme itself and the products of its action on the pectic fraction of P. marcgravii elicited the production of defensive compounds in the leaves of the plant. These results suggest that, besides the role in recycling organic matter, saprobes may also play an important role in the induction of defensive mechanisms in wild plants by enhancing their non-specific resistance against pathogens. Furthermore, they set the stage for future studies on the role of saprobic fungi in inducing resistance of host plants to pathogens. (AU)

FAPESP's process: 98/05124-8 - Conservation and sustainable use of the plant biodiversity from the cerrado and Atlantic Forest: the storage of carbohydrates and their role on the adaptation and maintainance of plants in their natural environment
Grantee:Marcos Silveira Buckeridge
Support Opportunities: BIOTA-FAPESP Program - Thematic Grants