Cellulase 생산균주의 Screening 및 Bacillus licheniformis CEL-2 유래 Cellulase 특성 규명 = Screening of Cellulolytic Microorganism and Characterization of Cellulase from Bacillus licheniformis CEL-2

다국어 초록 (Multilingual Abstract)

We carried out screening of microorganisms producing cellulase from Korean traditional fermented foods. As a result, we isolated 5 strains as cellulolytic microorganisms due to their ability of forming active zone on LB-Agar plate containing carboxymethylcellulose (CM-cellulose) as substrate with trypan blue. Among one of the strains, one strain was selected because its culture supernatant showed the highest cellulase activity for CM-cullulose. In the analysis of 16S rRNA gene sequence from the strain, the isolated strain showed 99% of identity with Bacillus licheniformis, therefore we named the strain Bacillus licheniformis CEL-II. The optimum pH and temperature of cellulase from B. licheniformis CEL-II were the highest activities at pH 5.0 and 60 o C, respectively. In the investigation of cellulase activity for several substrates such as CM-cellulose, alkali swollen cellulose, α-cellulose, Sigma Cellulose and Avicel, the cellulase from B. licheniformis CEL-II showed the highest activity for CM-cellulose. From the analysis of enzyme reaction products obtained from the hydrolysis of alkali swollen cellulose, the cellulase from B. licheniformis CEL-II was characterized to be an endo-type enzyme because the various size cellooligosaccharides were detected as main products on the analysis by thin-layer chromatography.