The Extracellular α-Amylase of Bacillus stearothermophilus

摘要: During the course of an investigation synthesis and secretion bacterial extracellular enzymes, Bacillus stearothermophilus α-amylase was found to be different from that previously described. Repetition purification procedure for enzyme yielded crystals which were identical in appearance with those reported B. α-amylase, but are not fact enzyme. A new has been devised. The purified have properties unique ones described resembled other α-amylases. molecular weight approximately 53,000, it also enzymes lacking cyst(e)ine. Although capable hydrolyzing starch at temperatures 70° above, did possess unusual thermostability. protected thermal denaturation above 55° by metal ions, particularly Ca2+, protein. is 50% inactivated 24 hours 6° while completely stable 25°. It concluded studied here does semi-random coil structure produced stearothermophilus.