초록
영어
The mannanase-producing bacteria, designated YJ17, was isolated from spent mushroom (Flammulina velutipes) substrates. The isolate YJ17 was a facultative anaerobic and was grown at temperatures ranging from 20oC to 50oC with an optimal temperature of 40oC. The DNA G+C content of the YJ17 was 44 mol%. The major fatty acids were anteiso-15:0 (38.9%), 17:0 (7.6%), and iso-15:0 (36.5%). The 16S rRNA gene sequence similarity between the isolate YJ17 and other Bacillus strains was from 98% to 99%. In the phylogenetic analysis based on these sequences, the isolate YJ17 and Bacillus amyloliquefaciens clustered within a group together and separated from other species of Bacillus. Based on the physiological and molecular properties, the isolate YJ17 was classified within the genus Bacillus as B. amyloliquefaciens YJ17. The optimal pH and temperature for mannanase activity of B. amyloliquefaciens YJ17 were pH 7.0 and 50oC, respectively.
목차
Introduction
Materials and Methods
Isolation of mannanase-producing bacteria from spent mushroom substrates
Morphological characteristics
Fatty acid methyl ester analysis
Utilization of carbon source
DNA base composition
Sequencing of 16S rRNA gene
Sequence comparison and phylogenetic analysis
Enzyme assays
Results and Discussion
Screening of mannan-degrading bacteria from from spent mushroom substrates
Morphological and physiological characteristics
Chemotaxonomy
16S rRNA sequence analysis
Effect of temperature and pH on mannanase activity
References