Nitrophorins - Lipocalin-based heme proteins transporting nitric oxide
Nitrophorins - Lipocalin-based heme proteins transporting nitric oxide
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DOI：
10.1002/bmb.2002.494030010016
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发表时间：
2002-01-01
影响因子：
1.4
通讯作者：
Montfort, WR
中科院分区：
文献类型：
--
作者：
Ascenzi, P;Nardini, M;Montfort, WR
1 - 4型含氮氧化物转运蛋白（NPs；NP1至NP4）是吸血昆虫长红猎蝽（Rhodnius prolixus）分泌的唾液血红素蛋白。NPs将一氧化氮（NO）传递给受害者，导致血管舒张，隔离组胺，减少宿主的炎症和免疫反应，并抑制血液凝固。NP的折叠结构基于一个八链反平行β -桶状结构，这通常在载脂蛋白家族中可见，该结构包含一个血红素基团。尽管NPs利用高铁血红素结合NO和组胺，但它们与六/八α -螺旋（无）脊椎动物血红蛋白无关，后者优先将NO结合到亚铁血红素上，但不结合组胺。因此，NPs和血红蛋白可被视为一种进化实验，其中血红素基团已适应结构不同的蛋白质家族以实现相似的功能。
Nitrophorins 1-4 (NPs; NP1 to NP4) are salivary heme proteins secreted from the blood-sucking insect Rhodnius prolixus. NPs transfer nitric oxide (NO) to the victim, resulting in vasodilatation, sequester histamine, reducing host inflammation and immune response, and inhibit blood coagulation. The NP fold is based on an eight-stranded antiparallel beta-barrel, typically observed in the lipocalin homology family, which hosts a heme group. Although NPs use the ferric heme to bind NO and histamine, they are unrelated to the six/eight alpha-helix (non)vertebrate hemoglobins, which bind NO preferentially to the ferrous heme, but do not bind histamine. Therefore, NPs and hemoglobins can be considered as an evolutionary experiment, where the heme group has been adapted to structurally different protein families to achieve similar function(s).