Production of pectolytic and macerating enzyme by Phoma strasseri

Abstract

1972. Production of pectolytic and macerating enzyme by Phornn strasseri. Can. J. Microbiol. 18: 1065-1072. Pectolytic enzyme activity of P. strasseri was highest in filtrates from cultures 5 and 23 days old, as determined by reducing-groups assay (RGA). Pectolytic enzyme activity, as determined by viscosityreduction assay (VRA), was highest in cultures 7 days old. Macerating enzyme activities were highest in cultures 10 days old. Young peppermint-rhizome sections were more susceptible to maceration by P.strasseri filtrates than older sections. Colored phenolic compounds were released from macerated rhizomes and amounts released were correlated with degree of maceration.Differential inhibition of pectolytic enzyme activity (as judged by VRA and RGA assays) by a range of phenolic compounds suggests that at least two pectolytic enzymes capable of hydrolyzing u-1,4 linkages of pectic substances are produced by P. strasseri. Highest activities of pectolytic and macerating enzyme in extracts from diseased rhizomes were detected 5 days after inoculation with P. strasseri. Extracts from healthy rhizomes did not show pectolytic and macerating enzyme activity. Healthy peppermint-rhizome tissues had higher activities of polyphenoloxidase than diseased tissues; also, polypl~enoloxidase activities in inoculated rhizomes decreased as time of incubation increased.

Pathogenicity and Ultrastructural Studies of the Mode of Penetration by Phoma strasseri in Peppermint Stems and Rhizomes

“…foveata (Giebel and Dopierała, 2004) and P. multirostrata (Garibaldi et al, 2010). e fact that the disease symptoms on the inoculated peppermint parts are similar to those that are observed in the conditions of field cultivation is certainly related to the production of pectolytic enzymes, especially polygalacturonase and maceration enzymes, by P. strasseri (Melouk and Horner, 1972a). It follows from studies conducted by Melouk and Horner (1972b) that enzymes of P. strasseri show the greatest activity 5 days a er infection.…”

The Relationship of Phenols and Oxidative Enzymes with the Resistance of Hevea to South American Leaf Blight

“…Polyphenol oxidase activities seemed to bt suppressed after inoculation of resistant Hevea leaves. MELOUK and HORNER (1972) also detected lower polyphenol oxidase activities in diseased peppermint infected with Phoma strasseri Moesz. They attributed the lowering polyphenol oxidase activities to continuous contact between the enzyme and the oxidized substrate which inhibited enzyme activity.…”