Expression, purification, and characterization of a thermophilic neutral protease from Bacillus stearothermophilus in Bacillus subtilis
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The gene coding for a thermophilic neutral protease from Bacillus stearothermophilus was expressed in Bacillus subtilis DB104, under the control of the sacB gene promoter. This was followed by either the native signal peptide sequence of this protease or the signal peptide sequence of the sacB gene. The protease was purified 3.8-fold, with a specific activity of 16530 U mg−1. As analyzed by SDS-PAGE, the molecular mass of the expressed protease was about 35 kDa, and the optimal temperature and pH of the protease were 65°C and 7.5, respectively. Moreover, it still had about 80% activity after 1 h reaction at 65 °C.
KeywordsBacillus subtilis thermophilic neutral protease expression purification characterization
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- 3.Ward O P. Proteolytic Enzymes. Oxford: Pergamon Press, 1985, 789–818Google Scholar
- 13.Huang G R, Ying T J, Huo P, et al. Purification and characterization of a protease from Thermophilic bacillus strain HS08. Afr J Biotechnol, 2006, 5(24): 2433–2438Google Scholar
- 15.Goeddle D V. Expression in B. subtilis. Meth Enzymol, 1990, 85: 199–228Google Scholar
- 17.Sambrook J, Fritsch E F, Maniatis T. Molecular Cloning: A Laboratory Manual. 2nd ed. New York: Cold Spring Harbor Laboratory, 1989Google Scholar
- 21.Priest F G. Extracellular enzyme synthesis in the genus Bacillus. J Bacteriol, 1977, 41: 711–753Google Scholar
- 22.Ayusawa D, Yoneda Y, Yamane K, et al. Pleiotropic phenomena in autolytic enzyme(s) content, flagellation, and simultaneous hyperproduction of extracellular α-amylase and protease in a Bacillus subtilis mutant. Bacteriol, 1975, 124: 459–469Google Scholar