Numan Özcan

Expression of thermostable α-amylase gene fromBacillus stearothermophilus in variousBacillus subtilis strains

The recombinant plasmid pC194Amy harbouring 5.25 kbp DNA fragment encoding the thermostable α-amylase gene ofBacillus stearothermophilus was introduced intoBacillus subtilis YB886 andB. subtilis BR151 strains by electroporation. The expressing of the α-amylase gene in recombinant strains were confirmed on starch plate, SDS-PAGE and zymogram analysis. In the condition of 100°C and 15 min, YB886Amy, BR151Amy and ATCC31786 α-amylases were maintained up to 80, 67 and 52% of their maximum activity respectively. The specific enzyme activities of YB886Amy, BR151Amy and ATCC 31786 were estimated as 2.59, 2.98 and 2.9 μM/mg protein/min respectively.