Purification and characterization of an iron stress-induced chlorophyll-protein from the cyanobacterium Anacystis nidulans R2.
Purification and characterization of an iron stress-induced chlorophyll-protein from the cyanobacterium Anacystis nidulans R2.
复制标题
DOI：
10.1016/0005-2728(88)90211-3
复制
发表时间：
1988-09
期刊：
影响因子：
--
通讯作者：
Harold C. Riethman;Louis A. Sherman
中科院分区：
文献类型：
--
作者：
Harold C. Riethman;Louis A. Sherman
AnacystisnidulansR 2叶绿素蛋白与铁胁迫细胞中的光系统II相关（Pakrasi，H.B.，Riethmann，H.C.还有洛杉矶的谢尔曼等人（1985）Proc. Acad. Sci. USA 82，6903-6907）进行了生物化学纯化和表征。用十二烷基-β-d-麦芽糖苷溶解的缺铁细胞膜进行阴离子交换层析，以高产率和相对天然的状态回收该叶绿素蛋白（CPVI-4）。CPVI-4在671 nm处具有室温吸收最大值，在681 nm处具有77 K叶绿素荧光峰，并且含有36、34和12 kDa的多肽。36和34 kDa的多肽与纯化的CPVI-4的轻度变性丙烯酰胺凝胶上的叶绿素相关，尽管只有34 kDa的蛋白质与针对凝胶纯化的叶绿素蛋白引起的抗血清具有免疫反应性。用十二烷基-β-d-麦芽糖苷溶解的膜级分和纯化的CPVI-4进行的免疫印迹实验表明，CPVI-4不包含先前鉴定的光系统III核心蛋白。CPVI-4可能在铁饥饿的细胞（其中藻胆体不存在或减少）中起捕光天线复合物的作用，此外，在从铁胁迫恢复的早期阶段，在其组装期间，可能将叶绿素贡献给反应中心复合物。
AnAnacystis nidulansR2 chlorophyll-protein associated with Photosystem II in iron-stressed cells (Pakrasi, H.B., Riethmann, H.C. and Sherman, L.A. (1985) Proc. Natl. Acad. Sci. USA 82, 6903–6907) has been biochemically purified and characterized. Anion exchange chromatography of dodecyl-β-d-maltoside-solubilized membranes from iron-defecient cells was used to recover this chlorophyll-protein (termed CPVI-4) in high yield and in a relatively native state. CPVI-4 has a room temperature absorption maximum at 671 nm, a 77 K chlorophyll fluorescence peak at 681 nm, and contains polypeptides of 36, 34 and 12 kDa. The 36 and 34 kDa polypeptides are associated with chlorophyll on mildly denaturing acrylamide gels of purified CPVI-4, although only the 34 kDa protein is immunoreactive with antisera elicited against the gel-purified chlorophyll-protein. Immunoblotting experiments with dodecyl-β-d-maltoside-solubilized membrane fractions and purified CPVI-4 indicate that CPVI-4 does not contain previously identified Photosystem III core proteins. CPVI-4 likely functions as a light-harvesting antenna complex in iron-starved cells (where phycobilisomes are absent or diminished) and, in addition, may contribute chlorophyll to the reaction center complexes during their assembly in the early stages of recovery from iron stress.