Fig 1.
The colony morphology (A) and gram stain (B) of murine bacteria strain SD8.
Table 1.
Morphological and biochemical characteristics of strain SD8.
Fig 2.
Electrophoregram of PCR products of strain SD8.
Fig 3.
Phylogenetic tree analysis of strain SD8 based on comparison of its 16S rDNA sequence with those of closely related strains.
The sequence of the 16S rDNA of E. coli was used as an outgroup. The tree was generated using the neighbor-joining v method.
Fig 4.
Effects of medium types in influencing the production of alkaline protease from strain SD8.
The strain was cultured 48 h at 37°C. *P<0.05 and **P<0.01 compared to LB medium. All the data were given as means ± SEM (n = 3).
Fig 5.
Effects of carbon sources in influencing the production of alkaline protease from strain SD8.
LB medium without carbon added was selected as blank control. *P<0.05 and **P<0.01 compared to blank control. All the data were given as means ± SEM (n = 3).
Fig 6.
Effects of culture time in influencing the production of alkaline protease and growth from strain SD8.
The optimum medium was used. All the data were given as means ± SEM (n = 3).
Fig 7.
Effects of initial pH in influencing the production of alkaline protease from strain SD8.
The single factor investigated was selected at optimal conditions. *P<0.05 and **P<0.01 compared to pH 7.5. All the data were given as means ± SEM (n = 3).
Fig 8.
Effects of medium quantity in influencing the production of alkaline protease from strain SD8.
The single factor investigated was selected at optimal conditions. *P<0.05 and **P<0.01 compared to 20 mL/100 mL Erlenmeyer flask. All the data were given as means ± SEM (n = 3).
Fig 9.
Effects of inoculum size in influencing the production of alkaline protease from strain SD8.
The single factor investigated was selected at optimal conditions. **P<0.01 compared to 3% inoculum size. All the data were given as means ± SEM (n = 3).