Mycosphaerella graminicola produces a range of cell wall-degrading enzyme activities in vitro that vary with the carbon source

Abstract

In this study, two Mycosphaerella graminicola isolates produced a range of cell wall-degrading enzymes (CWDE) in vitro that can potentially degrade wheat cell walls. The influence of three carbon sources on CWDE in vitro production was tested: 1) 1 % galactose (w/v), 2) 1% wheat cell walls (w/v) and 3) a mixture of 1% galactose (w/v) and 1% wheat cell walls (w/v). Six major activities produced by both isolates were detected: xylanase, b-1,3-glucanase, polygalacturonase, cellulase, b-xylosidase and b-galactosidase. Time-course experiments showed that different levels of enzyme activities were obtained with isolates 323 and 94269. These activities levels varied also with the type of carbon source used. Principal Component Analysis showed that the enzyme activities are gathered into two groups. None of the activities of the first group was correlated to the activities of the second group. It also showed that the optimal medium that allowed the production of most of the major activities contained both galactose and wheat cell walls.

Cell-wall-degrading enzymes produced in vitro and in vivo byRhizoctonia solani, the causative fungus of peanut sheath blight

“…Our results agreed with the reports of Dong et al (2010) and Zhang, Bruton & Biles (2014) . In contrast to the current results, Cx was not secreted by Mycosphaerella graminicola either in medium containing wheat cell walls or CMC as the carbon source ( Douaiher et al, 2007a ). From our data, we suggest that R. solani PG, PMG and Cx are substrate-inducible enzymes.…”

“…Cx degrades cellulose to cellobiose and is related to the virulence of pathogens ( Ikotun, 1984 ; Lalaoui et al, 2000 ; Yang et al, 2012b ; Zhao et al, 2014 ; Zhang, Bruton & Biles, 2014 ; Zhou et al, 2016 ). Many plant fungal pathogens have been reported to produce Cx in cultivation in infected host tissue, or both ( Ikotun, 1984 ; Lalaoui et al, 2000 ; Gao et al, 2000 ; Li et al, 2003 ; Chen et al, 2006 ; Douaiher et al, 2007a ; Dong et al, 2010 ; Yang et al, 2012b ; Zhang, Bruton & Biles, 2014 ; Zhao et al, 2014 ; Zhou et al, 2016 ). The activity of Cx produced by Didymella bryoniae in cultures and in decayed tissue positively correlated with disease severity ( Zhang, Bruton & Biles, 2014 ; Zhou et al, 2016 ).…”

Enzymatic activities produced by mixed Saccharomyces and non-Saccharomyces cultures: relationship with wine volatile composition

“…Our results indicate that enzyme activities fluctuated, making it impossible to establish trends over the process. Therefore, we decided to calculate the AUEC because it represents properly the enzymes behavior throughout the process (Douaiher et al 2007). Based on the methodology used for the analyzing of the experimental data, we can assert that there is no direct relationship between enzymatic activities and biomass detected.…”

Protective and curative efficacy of prothioconazole against isolates of Mycosphaerella graminicola differing in their in vitro sensitivity to DMI fungicides

“…These two observations confirm that aggressiveness is not directly related to the DNA amount, and that the relation between fungal DNA amount and the level of disease symptoms is clearly dependent on the isolate. In fact, the necroses are associated with wall‐degrading enzymes produced by the fungus (particularly xylanase),20–22 and more aggressive isolates could arguably present a higher enzyme activity, with no relation to DNA amount.…”