Cellulase Characteristics And Genome Libraris Construction Of A Strain Of Novel Cellulolytic Bacterium

Cellulose material is the most abundant organic material and renewable resource in nature. Currently, utilization of non-renewable resource has appearred a very great crisis with the boom of global population and the increase of non-renewable resource utilization around the world. In contrast, utilization of cellulose resource has a very promising prospect by virtue of their plentful supply and low cost. However,high crystal feature of cellulose material has produced a very great impediment to its full scale degradation and utilization. Therefore, sicentists have attached a very great importance to bio-conversion study on the hydrolysis and utilization of cellulose materials.Aiming at hotspot problems involved in the process of the degradation and utilization of cellulose material, the paper developed correlative research work involving the following aspects that developing cellulolytic microbiology resources, cellulase characteristics analysis and genome libraries construction of cellulolytic strain, respectively. First of all, a strain of cellulolytic bacterium was isolated from soil. The isolate could excrete a mass of cellulases and strongly degrade cellulose material. The phenotypic characteristics and physiological properties of the strain were determined with polyphasic taxonomy technique. The G+C content of the strain was 53.07 mol%. Analysis based on 1440bp length 16S rDNA sequence similarity indicated that the strain is closely related to Vibrio. scophthalmi with 97.92% sequence similarity. The analysis based on physiological and biochemical characteristics and 16S rDNA gene sequence similarity and the G+C content of genome indicated that isolate should be a novel species of cellulolytic Vibrio genus. All sequence alignments of 16S-23S rDNA Internal Spacer Regions(ISRs)indicated that consensus region is tRNAala和tRNAile, variable region is not homologous.The cellulase system extreted by the strain contained three kind proteins of CMCase, EG and BGL, and their proportion are 3.1:1.4:1.0 in cellulase system. The optimum pH value of cellulase system activity under various pH conditions are ranged from 5.0 to 5.5. At the same time, the optimum temperature of cellulase system activity is 50℃. The effect of various metal ions on carboxymethylcellulase...