Plant cell wall degradation by Aspergillus nidulans

Sunita Macwana1, Anamika Ray2, Rolf A. Prade1 and Andrew Mort2

Author address: 

1Department of Microbiology & Molecular Genetics and 2 Biochemistry & Molecular Biology, Oklahoma State University, Stillwater OK 74078


Little is known about the plant cell wall degrading enzymes produced by A. nidulans while growing on plant cell walls. Our study is based on a molecular negative screening method, specifically directed to recover cDNA clones from ALL transcripts A. nidulans induces when shifted from growth on glucose to a range of cell wall polysaccharides including pectins, cellulose and xylan. cDNAs prepared from mRNA of tissues grown in glucose were labeled and used to probe a cDNA-plasmid library made from mRNAs extracted from tissues grown on cell wall polysaccharides. Transcripts present in both, the probe and the plasmid library, appear as positives whereas transcripts expressed only in the plasmid library are the negatives (not labeled). A two-staged screening method was devised to allow the survey of a large number of clones for identification of putative negatives in the initial stage followed by reliable confirmation of clones that are not expressed or present in low abundance in the probe originating condition. A statistically significant collection of negatives has been isolated and sequenced for a digital gene expression profiling and functional annotation analysis. Genes recognized through this method, are the ones upregulated as a result of the physiological shift (change in carbon source). Thus, the suggested approach is comprehensive because one can identify whole gene sets activated by a special physiological condition

abstract No: 


Full conference title: 

21st Fungal Genetics Conference
    • Fungal Genetics Conference 21st (2000)