Digestive proteolysis organization in two closely related Tenebrionid beetles: red flour beetle (Tribolium castaneum) and confused flour beetle (Tribolium confusum).
Digestive proteolysis organization in two closely related Tenebrionid beetles: red flour beetle (Tribolium castaneum) and confused flour beetle (Tribolium confusum).
复制标题
两种密切相关的拟步甲虫的消化蛋白水解组织：赤拟谷盗 (Tribolium castaneum) 和混淆谷盗 (Tribolium confusum)。
DOI：
10.1002/arch.20299
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发表时间：
2009
影响因子：
2.2
通讯作者：
F. Sehnal
中科院分区：
文献类型：
--
作者：
K. Vinokurov;E. Elpidina;D. Zhuzhikov;B. Oppert;D. Kodrík;F. Sehnal
赤拟谷盗Tribolium castaneum和赤拟谷盗T.混淆幼虫消化肽酶的特点是相对于在中肠蛋白质消化的空间组织。两种中肠内容物的pH值均从前中肠的5.6-6.0增加到后中肠的7.0-7.5。然而，来自任一昆虫的肠提取物的总蛋白水解活性的最适pH为pH 4.1。大约80%的总蛋白水解活性是在前面和20%的后部中肠的任一昆虫时，在缓冲液中模拟的pH值和还原条件下的每个中肠部分的特征进行评估。在pH5.6缓冲液中，来自任一昆虫的肠提取物的一般肽酶活性主要是由于半胱氨酸肽酶。在后中肠的弱碱性条件下，丝氨酸肽酶的贡献率分别为31%和41%。castaneum和T.混淆，分别。明胶电泳后肽酶活性测定也揭示了半胱氨酸肽酶在两种拟谷盗属物种蛋白质消化中的重要贡献。使用对硝基苯胺底物和特异性抑制剂进行电泳后活性测定，发现了一组半胱氨酸和丝氨酸内肽酶，T. castaneum，T.混淆，分别。丝氨酸肽酶包括胰蛋白酶，胰凝乳蛋白酶，和弹性蛋白酶样酶，后者是首次在拟步甲昆虫。这些数据支持了一个复杂的系统，蛋白质消化的拟谷盗中肠的半胱氨酸肽酶的基本作用。
The spectra of Tribolium castaneum and T. confusum larval digestive peptidases were characterized with respect to the spatial organization of protein digestion in the midgut. The pH of midgut contents in both species increased from 5.6-6.0 in the anterior to 7.0-7.5 in the posterior midgut. However, the pH optimum of the total proteolytic activity of the gut extract from either insect was pH 4.1. Approximately 80% of the total proteolytic activity was in the anterior and 20% in the posterior midgut of either insect when evaluated in buffers simulating the pH and reducing conditions characteristic for each midgut section. The general peptidase activity of gut extracts from either insect in pH 5.6 buffer was mostly due to cysteine peptidases. In the weakly alkaline conditions of the posterior midgut, the serine peptidase contribution was 31 and 41% in T. castaneum and T. confusum, respectively. A postelectrophoretic peptidase activity assay with gelatin also revealed the important contribution of cysteine peptidases in protein digestion in both Tribolium species. The use of a postelectrophoretic activity assay with p-nitroanilide substrates and specific inhibitors revealed a set of cysteine and serine endopeptidases, 8 and 10 for T. castaneum, and 7 and 9 for T. confusum, respectively. Serine peptidases included trypsin-, chymotrypsin-, and elastase-like enzymes, the latter being for the first time reported in Tenebrionid insects. These data support a complex system of protein digestion in the Tribolium midgut with the fundamental role of cysteine peptidases.
影响因子：
2.9
作者：
MCLELLAN, T
通讯作者：
MCLELLAN, T