哺乳动物和昆虫碳酸酐酶的比较特性：钾和氯对二氧化碳水合速率的影响。

Comparative properties of mammalian and insect carbonic anhydrases: effects of potassium and chloride on the rate of carbon dioxide hydration.

Johnston J W, Jungreis A M

Department of Zoology, University of Tennessee, Knoxville 37916.

Comp Biochem Physiol B. 1979;62(4):465-9. doi: 10.1016/0305-0491(79)90119-6.

Abstract

Carbonic anhydrase (E.C.4.2.1.1) catalysed CO2 hydration was studied with enzymes from mammalian and insect sources at CO2 concentrations of 7.6-30.8 mM. 2. At 0.01-0.15 M, potassium chloride (KCl) or choline chloride (ChCl) markedly inhibited all 8 mammalian enzymes studied. 3. Inhibition by KCl is always greater than that associated with ChCl. 4. KCl non-competitively inhibits and choline chloride competitively inhibits bovine carbonic anhydrase. 5. Carbonic anhydrase obtained from fat body, integumentary epithelium and midgut tissues of larval tobacco hornworms, Manduca sexta, is greatly stimulated by KCl and slightly inhibited by ChCl. 6. We propose that the effect of K+ on mammalian and insect carbonic anhydrases if fundamentally different.

摘要

在二氧化碳浓度为7.6 - 30.8 mM的条件下，研究了来自哺乳动物和昆虫源的碳酸酐酶（E.C.4.2.1.1）催化的二氧化碳水合作用。2. 在0.01 - 0.15 M时，氯化钾（KCl）或氯化胆碱（ChCl）显著抑制了所研究的所有8种哺乳动物酶。3. KCl的抑制作用总是大于与ChCl相关的抑制作用。4. KCl对牛碳酸酐酶有非竞争性抑制作用，而氯化胆碱有竞争性抑制作用。5. 从烟草天蛾幼虫（Manduca sexta）的脂肪体、体表上皮和中肠组织中获得的碳酸酐酶受到KCl的极大刺激，并受到ChCl的轻微抑制。6. 我们认为K⁺对哺乳动物和昆虫碳酸酐酶的作用在根本上是不同的。