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Rasmussen, Mark Axel 2014-12-16T19:35:28Z 2014-12-16T19:35:28Z 10000-01-01 1986 1986 Cellulose degradation by Ruminococcus flavefaciens and other ruminal cellulolytic bacteria was strongly inhibited by highly substituted methyl celluloses (degree of substitution > 1.5 and mol wt > 12,000). The inhibitory response was concentration dependent with 0.1% (wt/vol) or methyl cellulose required for complete inhibition. R. flavefaciens was unable to use methyl cellulose for growth and no bacterial depolymerization of methyl cellulose was observed. Bacterial adherence to cellulose also was inhibited by the cellulose derivatives. Crude mixtures of methylated cellulodextrins (average degree of polymerization (DP) = 9.4 and 8.5) prepared from methyl cellulose by mild acid hydrolysis (2 N HCl) partially inhibited cellulose degradation by R. flavefaciens. Inhibition did not occur with extended hydrolysis preparations (DP = 4.5 and 1.0) nor with the addition of 3-O-methyl-(beta)-D-glucose. Similar inhibitory responses were observed on cellulose-grown cultures of R. flavefaciens using a p-nitrophenyl-(beta)-D-cellobioside enzyme assay. Cellulodextrins (DP = 3 - 7) synthetically methylated also inhibited enzymatic activity, however no inhibition was observed when glucose or cellobiose were similarly derivatized. A direct relationship between degree of inhibition and DP was suggested by these data. The recalcitrant nature of methyl celluloses and their inhibitory activities make these compounds important tools in the study of bacterial adherence to cellulose, cellulase enzymology and bacterial carbohydrate metabolism. Made available in DSpace on 2014-12-16T19:35:28Z (GMT). No. of bitstreams: 1 8701596.pdf: 4841479 bytes, checksum: 7d06e442a9c05fc66bc21346326192e9 (MD5) Previous issue date: 1986 Embargo set by: Seth Robbins for item 71894 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 144 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986. http://hdl.handle.net/2142/71728 (UMI)AAI8701596 Biology, Microbiology Effects of Methyl Cellulose on the Cellulolytic Bacterium, Ruminococcus Flavefaciens (Rumen, Anaerobe) text Animal Science Dairy Science University of Illinois at Urbana-Champaign Dissertation Ph.D.