Podoler H, Applebaum S W
Biochem J. 1971 Jan;121(2):321-5. doi: 10.1042/bj1210321.
C. chinensis larval amylase is activated by Ca(2+) and inhibited by Cl(-) and EDTA (K(i) 6.7x10(-3)m). GSH and 2-mercaptoethanol activate, presumably at different sites, as 2-mercaptoethanol interferes with Ca(2+) activation, whereas GSH enhances it. The inhibition by iodoacetic acid and N-ethylmaleimide (K(i) 1.55x10(-2)m) suggest that free thiol groups are essential for activity. The pH optimum of 5.2-5.4 is moved to 5.6-5.8 by Ca(2+) and 2-mercaptoethanol. The activation energy is 7270 cal/mol, and is not affected by Ca(2+) and 2-mercaptoethanol. K(m) for soluble starch is 2.3mg/ml.
中华哲水蚤幼虫淀粉酶被Ca(2+)激活，被Cl(-)和EDTA（抑制常数K(i)为6.7×10(-3)m）抑制。谷胱甘肽（GSH）和2-巯基乙醇激活该酶，推测是在不同位点，因为2-巯基乙醇干扰Ca(2+)激活，而GSH增强这种激活作用。碘乙酸和N-乙基马来酰亚胺的抑制作用（抑制常数K(i)为1.55×10(-2)m）表明游离巯基对酶活性至关重要。Ca(2+)和2-巯基乙醇可使最适pH从5.2 - 5.4变为5.6 - 5.8。活化能为7270卡/摩尔，不受Ca(2+)和2-巯基乙醇影响。可溶性淀粉的米氏常数K(m)为2.3毫克/毫升。
