Abstract
Two solid pectic media were devised for mutually exclusive detection of extracellular polygalacturonase and pectin lyase produced by fungi including the vascular parasite of tomato Verticillium albo-atrum. These media allowed detection of pectinase-defective mutants. Polygalacturonase detection medium contains non-methylated polygalacturonan (sodium polypectate) is buffered at pH 5.0 (Na citrate, 0.05 M) and is calcium-free. In contrast pectin lyase medium contains polymethylgalacturonan (pectin), is buffered at pH 8.0 (HEPES, 0.05 M) and contains calciumrich agar. When glucose was added to the media for selection of catabolite-resistant mutants, enzyme synthesis was still evident, whereas in comparable conditions in liquid culture production was almost completely repressed. This apparent discrepancy is discussed in terms of the influence of basal synthesis, colony biomass and accumulation of oligouronides which repress induced synthesis and activity.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
