Release of Cell Wall Degrading Enzymes from Conidia of Blumeria graminis on Artificial Substrata.

Abstract

Cellulase and pectinase activities were

The roles of cellulase enzymes and mechanical force in host penetration by Erysiphe graminis f.sp.hordei

“…This may be due to the antigen(s) being too diffuse for visible immunofluorescence prior to induction of germination, or, more likely, the absence of cellulase enzymes at this time. Indeed, this is supported by the recent work of Suzuki et al [22 ] who reported the release of exudates with cellulase activity at 1, 6 and 16 hpi on cellulose membrane but no surface cellulase activity in ungerminated spores. However, Suzuki et al [22 ] found evidence for cellulase activity in homogenized conidia.…”

“…Indeed, this is supported by the recent work of Suzuki et al [22 ] who reported the release of exudates with cellulase activity at 1, 6 and 16 hpi on cellulose membrane but no surface cellulase activity in ungerminated spores. However, Suzuki et al [22 ] found evidence for cellulase activity in homogenized conidia. Taken collectively, these data imply that cellulases are '' released '' from the primary and appressorial germ tubes but not in the liquid exudate released by ungerminated conidia upon initial contact with cellulose membrane [22 ].…”

“…Whereas some workers have failed to find cellulase activity in E. graminis conidia [5,10 ], others have found low levels of cellulase activity [13 ]. A recent study indicated that although cellulase was undetectable in ungerminated conidia, cellulase activity was present in washings taken from germinated conidia that had differentiated mature appressoria on artificial substrate [22 ]. It is well established that turgor pressures developed within the appressoria of some pathogenic fungi are sufficiently high to support physical puncture of the host cell wall by the penetration peg.…”

Gene Identification in the Obligate Fungal Pathogen Blumeria graminis by Expressed Sequence Tag Analysis

“…Suzuki et al (1998) have shown that B. graminis germlings secrete carboxymethyl cellulases and exo-␤-glucanases during germination. Immunolocalization studies have confirmed the presence of cellobiohydrolase I and II at the tips of primary and appressorial germ tubes (PryceJones et al, 1999).…”

Cloning and Sequence Analysis of Endopolygalacturonase Genes in Venturia nashicola and Venturia pirina

“…tritici 43 , and apple scab fungus Venturia inaequalis 47 , has also been initiated. An exoPG from mycelia of the V. pirina 20 and 3 endoPGs from mycelia of the V. nashicola races 1, 2 and 3 were also previously purified 20 .…”