HYDROLYSIS OF FRACTION-1 LEAF PROTEIN AND CASEIN BY RUMEN ENTODINIOMORPHID PROTOZOA
HYDROLYSIS OF FRACTION-1 LEAF PROTEIN AND CASEIN BY RUMEN ENTODINIOMORPHID PROTOZOA
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DOI：
10.1111/j.1365-2672.1983.tb02654.x
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发表时间：
1983-01-01
期刊：
影响因子：
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通讯作者：
COLEMAN, GS
中科院分区：
文献类型：
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作者：
COLEMAN, GS
14种植物的无细胞提取物。瘤胃纤毛虫原生动物[来自绵羊]和混合瘤胃纤毛虫降解部分1叶蛋白。尾甲藻和巨真甲藻的最适pH为3.2。体内生长的原生动物的最大蛋白水解速率（μ mol酸溶性-形成的酪氨酸/mg蛋白/h）为0.16-5.7，体外生长的原生动物的最大蛋白水解速率为0.38-6.4。E. caudatum和E.单纯型和体内生长的纤维素分解种最低。Km值（mg/ml）范围为0.42-19与原生动物在体内生长和0.35-13.3与原生动物在体外生长。无论是在体内还是体外生长，所有单一物种（有一个例外）降解级分1叶蛋白的速度都比酪蛋白快（1.4-21倍）。部分抑制E.用胃蛋白酶抑制剂和N-乙基马来酰亚胺获得尾状体，用亮抑酶肽几乎完全抑制，表明存在羧基和巯基酶。
Cell-free extracts of 14 spp. of rumen ciliate protozoa [from sheep] and of mixed rumen ciliates degraded fraction 1 leaf protein. For Entodinium caudatum and Eudiplodinium maggii the optimum pH was 3.2. The maximum rates of proteolysis (in .mu.mol acid soluble-tyrosine formed/mg protein/h) were 0.16-5.7 with protozoa grown in vivo and 0.38-6.4 with protozoa grown in vitro. The highest rates were obtained with E. caudatum and E. simplex and the lowest with the cellulolytic species grown in vivo. Km values (mg/ml) ranged from 0.42-19 with protozoa grown in vivo and 0.35-13.3 with protozoa grown in vitro. All single species (with one exception) whether grown in vivo or in vitro degraded fraction 1 leaf protein faster (1.4-21 times) than casein. Partial inhibition of the activity of E. caudatum was obtained with pepstatin and N-ethylmaleimide and almost complete inhibition with leupeptin, suggesting the presence of carboxyl and thiol enzymes.