Characterization of Bacteria Community Isolated from Wood Decay
Fatma Meddeb-Mouelhi
Centre de Recherche sur les Matériaux Lignocellulosiques, Université du Québec à Trois-Rivières, 3351 Boul. Des Forges, C.P. 500 Trois-Rivières (Québec) G9A 5H7, Canada and Buckman North America, 351 Joseph-Carrier, Vaudreuil-Dorion (Québec) J7V 5V5, Canada
Jessica Kelly Moisan
Centre de Recherche sur les Matériaux Lignocellulosiques, Université du Québec à Trois-Rivières, 3351 Boul. Des Forges, C.P. 500 Trois-Rivières (Québec) G9A 5H7, Canada and PROTEO, Université Laval, 2705 Boul. Laurier, Ste-Foy (Québec) G1V 4G2, Canada
Marc Beauregard *
Centre de Recherche sur les Matériaux Lignocellulosiques, Université du Québec à Trois-Rivières, 3351 Boul. Des Forges, C.P. 500 Trois-Rivières (Québec) G9A 5H7, Canada and PROTEO, Université Laval, 2705 Boul. Laurier, Ste-Foy (Québec) G1V 4G2, Canada
*Author to whom correspondence should be addressed.
Abstract
In order to discover enzymes having potential for wood fibre modification, bacteria (fourteen strains designated MMB1 to MMB14) were isolated from a decomposing stump from a resinous tree. Phylogenetic analysis and biochemical characterization indicated that these isolates were related to Microbacterium, Chryseobacterium, Lysinibacillus, and Bacillus gene; although most demonstrated phenotypic differences compared to previously characterized relatives. Only the Bacillus strains showed cellulolytic activity (as CMCase detected with Congo red) and only Bacillus subtilis strains (MMB10 to MMB14) displayed cellulolytic and secreted xylanase activity. Phenotypic characterization of two strains (MMB8 and MMB9) related to a previously characterized isolate (Bacillus sp. JU2), supported their reassignment to the genus Lysinibacillus. The Microbacterium strain MMB1 produced a green pigment when grown in the presence of light. Some microbes from the consortium were devoid of wood polymer modifying enzymes, and may be dependent on other organisms for their survival in this biotope.
Keywords: Cellulase, xylanase, wood decomposition, Lysinibacillus, photo-chromogenic bacteria, Microbacterium oxydans