, 2004) Cellulolytic communities have been identified in a wide

, 2004). Cellulolytic communities have been identified in a wide variety of sources such as biocompost, soil, decaying lignocellulose materials, and the feces of ruminants (Maki et al., 2009; Izquierdo et al., 2010). Although

the digestion of lignocellulose by terrestrial microorganisms has been widely studied, cellulolytic microorganisms in marine environments have received less attention. Early studies indicated that bacteria were the predominant degraders of lignocellulose in marine ecosystems, with the exception of marine animals such as teredinid bivalves (Benner et al., 1986; Distel, 2003). Recently, selleckchem an aerobic and mesophilic bacterium Saccharophagus degradans has been intensively studied (Taylor et al., 2006). However, few bacteria with strong cellulolytic activities have been isolated and characterized, especially anaerobic species. Given the diversity of habitats of the ocean, there exists the possibility of some efficient cellulose enzymatic digestion system in the marine ecosystems. For example, mangroves have been considered to be an important location for lignocellulose decomposition (Pointing & Hyde, 2000). The exploration of novel cellulose-degrading microbial communities is of particular importance in the identification of novel microorganisms. Because of its

high salinity (3%), the marine environment is likely to have evolved different cellulose-degrading microorganisms than the terrestrial environment. Studies of lignocellulose degradation under saline conditions have a great potential in the search Metformin for enzymes with novel catalytic properties and microorganisms with novel metabolic pathways. In this paper, an anaerobic and thermophilic cellulolytic community was enriched from a coastal marine sediment sample. To explore the community members of the unusual consortium, libraries of 16S rRNA gene and functional gene glycosyl hydrolase family 48 (GHF48) gene were constructed and analyzed. Thalidomide Samples collected from marine sediment of a coastal region of the Yellow Sea (36°5′N, 120°32′E), China, in July 2011, were used as inocula in 100 mL of basal

medium containing 1 g Avicel (PH-101; Sigma Aldrich, Shanghai, China) or a piece of filter paper (FP) (No. 1, Whatman) as the carbon source. The medium consisted of 0.1 g L−1 KH2PO4, 0.1 g L−1 K2HPO4, 1 g L−1 NaHCO3, 2 g L−1 (NH4)2SO4, 0.5 g L−1 l-cysteine, and 0.0001 (w/v) resazurin. Vitamins were added in the following concentrations (in mg L−1): pyridoxamine dihydrochloride, 1; p-aminobenzoic acid (PABA), 0.5; d-biotin, 0.2; vitamin B12, 0.1; thiamine-HCl-2 × H2O, 0.1; folic acid, 0.2; pantothenic acid calcium salt, 0.5; nicotinic acid, 0.5; pyridoxine-HCl, 0.1; thioctic acid, 0.5; riboflavin, 0.1. The samples were incubated under thermophilic (60 °C) and anaerobic conditions. Samples showing FP degradation were selected for further transfers. Cultures showing FP degradation were transferred five times to ensure their cellulose degradation ability.

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