Rathore R M, Kumar S, Chakrabarti R
Aqua Research Lab, Department of Zoology, University of Delhi, Delhi-110007, India.
Comp Biochem Physiol B Biochem Mol Biol. 2005 Sep;142(1):98-106. doi: 10.1016/j.cbpc.2005.06.007.
Digestive enzymes of Catla catla were studied during ontogenic development. Specific amylase activity was 0.12+/-0.01 mg maltose mg protein(-1) h(-1) in fish 4 days after hatching (DAH) and reached a maximum on (0.41+/-0.12 mg maltose mg protein(-1) h(-1)) 34 DAH. Total protease activity was minimum (123.2+/-16.5 mU mg protein(-1) min(-1)) on day-8 and reached its highest level (2713+/-147.2 mU mg protein(-1) min(-1)) on day-32. Trypsin activity showed constant increasing trend from day-16 onwards and was maximum on day-34 (118.1+/-7.09 mU mg protein(-1) min(-1)). Highest chymotrypsin activity was found on day-32 (1789.0+/-111.7 mU mg protein(-1) min(-1)). Lipase activity was detected in 4 DAH catla. Lipase activity increased steadily from day-22 onwards. SDS-PAGE of crude enzyme extracts showed that high molecular mass bands (41.8-127.8 kDa) appeared during the early stages followed by low molecular mass bands (17.8-37.2 kDa). The number of protease activity bands in substrate SDS-PAGE increased with age of fish. During ontogenesis of carp, soybean trypsin inhibitor (SBTI), PMSF and TLCK inhibited 75.5+/-1.19% to 92.8+/-0.85%, 53.3+/-9.47% to 90.5+/-2.6% and 39.8+/-3.8% to 84.7+/-1.54% of total protease activity, respectively. There was only 2.58+/-0.66% to 10.21+/-0.09% inhibition of protease activity with EDTA. SBTI and PMSF inhibited 8 and 4 activity bands, respectively. TLCK, a specific trypsin inhibitor, inhibited four trypsin-like enzymes in carp during ontogenesis.
在印度鲶鱼的个体发育过程中对其消化酶进行了研究。孵化后4天（DAH）的幼鱼中，淀粉酶比活性为0.12±0.01毫克麦芽糖/毫克蛋白质⁻¹小时⁻¹，并在34 DAH时达到最大值（0.41±0.12毫克麦芽糖/毫克蛋白质⁻¹小时⁻¹）。总蛋白酶活性在第8天最低（123.2±16.5毫单位/毫克蛋白质⁻¹分钟⁻¹），并在第32天达到最高水平（2713±147.2毫单位/毫克蛋白质⁻¹分钟⁻¹）。胰蛋白酶活性从第16天起呈持续上升趋势，并在第34天达到最大值（118.1±7.09毫单位/毫克蛋白质⁻¹分钟⁻¹）。在第32天发现糜蛋白酶活性最高（1789.0±111.7毫单位/毫克蛋白质⁻¹分钟⁻¹）。在4 DAH的印度鲶鱼中检测到脂肪酶活性。脂肪酶活性从第22天起稳步增加。粗酶提取物的SDS-PAGE显示，早期出现高分子量条带（41.8 - 127.8 kDa），随后是低分子量条带（17.8 - 37.2 kDa）。底物SDS-PAGE中蛋白酶活性条带的数量随鱼龄增加。在鲤鱼的个体发育过程中，大豆胰蛋白酶抑制剂（SBTI）、苯甲基磺酰氟（PMSF）和甲苯磺酰-L-赖氨酸氯甲基酮（TLCK）分别抑制总蛋白酶活性的75.5±1.19%至92.8±0.85%、53.3±9.47%至90.5±2.6%和39.8±3.8%至84.7±1.54%。用乙二胺四乙酸（EDTA）对蛋白酶活性的抑制率仅为2.58±0.66%至10.21±0.09%。SBTI和PMSF分别抑制8条和4条活性条带。TLCK是一种特异性胰蛋白酶抑制剂，在鲤鱼个体发育过程中抑制了四种类胰蛋白酶。
