Monday, April 19, 2010
3-12

Mining Dictyoglomus turgidum for enzymatically active carbohydrases

Phillip J. Brumm1, Spencer Hermanson1, Becky Hochstein2, Julie Boyum3, Nick Hermersmann3, Krishne Gowda3, and David Mead3. (1) C5-6 Technologies and Great Lakes Bioenergy Research Center, 2120 W Greenview Drive, Middleton, WI 53562, (2) Montana State University, 107 Chemistry/ Biochemistry Building, Bozeman, MT 59717, (3) Lucigen and Great Lakes Bioenergy Research Center, 2120 W Greenview Drive, Middleton, WI 53562

Dictyoglomus species represent a novel group of thermophilic, anaerobic organisms with considerable biotechnological promise; these organisms are so unique that they have been given their own genus, Dictoglomi. Dictyoglomus turgidum is an anaerobic, thermophile able to degrade a wide range of biomass components including starch, cellulose, pectin and lignin. The broad range of substrate utilization is reflected in the high percentage of CAZymes present in the genome, 2.35% of its total genes, higher than the percentage present in the cellulose-degrading, thermophilc anaerobe, Clostridium thermocellum, with 2.2% of its total genes.  This apparent strong degradation capacity, coupled with the uniqueness of the organism, suggested that D. turgidum would be an excellent source of new and novel biomass-degrading enzymes. Screening of a random clone library generated from D. turgidum resulted in the discovery of several novel biomass-degrading enzymes with low homology to known molecules. Whole genome sequencing of the organism followed by bioinformatics-directed amplification of selected genes resulted in the recovery of additional novel enzyme molecules.