Localization of carbonic anhydrase in legume nodules
Localization of carbonic anhydrase in legume nodules
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DOI：
10.1046/j.1365-3040.2001.00680.x
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发表时间：
2001-03-01
影响因子：
7.3
通讯作者：
Thumfort, P
中科院分区：
文献类型：
--
作者：
Atkins, C;Smith, P;Thumfort, P
羽扇豆 (Lupinus angustifolius L.)、豇豆 (Vigna unguiculata L. (Walp))、豌豆 (Pisum sativum L.)、菜豆 (Phaseolus vulgaris L.)、蚕豆 (Vicia faba L.) 和苜蓿 (Medicago sativa L.) 的根瘤中央感染区和周围皮层的提取物含有显着的碳酸酐酶 (CA) 活性。使用抗血清对从苜蓿克隆的推定根瘤 CA (Msca1) 的提取物进行免疫测定，也表明在两种组织类型中都有表达。使用激光扫描成像和荧光 CA 特异性探针（5-二甲基氨基萘-1-磺酰胺 [DNSA]）的定量共聚焦显微镜将表达定位于中心区组织中的感染细胞以及对应于内皮层的皮层组织中 2-3 列细胞的窄带。在受感染的细胞中，酶活性均匀分布在细胞质中，但在内皮层细胞中，酶活性仅限于外围 - 可能是质膜或细胞壁。 CA 在这两种组织中的功能被认为与结节的碳代谢和内皮层参与气体扩散阻力的调节有关。
Extracts of the central infected zone and the surrounding cortex of nodules from Lupinus angustifolius L., Vigna unguiculata L. (Walp), Pisum sativum L., Phaseolus vulgaris L., Vicia faba L. and Medicago sativa L. contained significant activities of carbonic anhydrase (CA). Immunoassay of extracts using antisera to a putative nodule CA (Msca1) cloned from M. sativa also indicated expression in both tissue types. Quantitative confocal microscopy using laser scanning imaging and a fluorescent CA-specific probe (5-dimethylaminonaphthalene-1-sulfonamide [DNSA]) localized expression to the infected cells in the central zone tissue and a narrow band of 2-3 files of cells in the cortical tissue that corresponded to the inner cortex. In the infected cells, the enzyme activity was distributed evenly in the cytosol, but in the inner cortical cells, it was restricted to the periphery - possibly to the plasma membrane or cell wall. The functions of CA in these two tissues are considered in relation to the carbon metabolism of nodules and the participation of the inner cortex in the regulation of gaseous diffusive resistance.