Isolation and characterization of the amino and carboxyl proximal fragments of the adenosine cyclic 3' ,5'-phosphate receptor protein of Escherichia coli.
Isolation and characterization of the amino and carboxyl proximal fragments of the adenosine cyclic 3' ,5'-phosphate receptor protein of Escherichia coli.
复制标题
大肠杆菌环 3,5-磷酸腺苷受体蛋白的氨基和羧基近端片段的分离和表征。
DOI：
10.1021/bi00519a038
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发表时间：
1981
期刊：
影响因子：
2.9
通讯作者：
Krakow,JS
中科院分区：
文献类型：
--
作者：
Aiba,H;Krakow,JS
Hiroji Aiba* 和Joseph S.克拉科夫 * 摘要：环磷酸腺苷受体蛋白（CRP）是大肠杆菌基因表达的正、负调控蛋白。该蛋白已被蛋白水解切割，以确定CRP结构和功能之间的关系。在十二烷基硫酸钠（Na-DodS_（04））存在下，胰凝乳蛋白酶将CRP分解为分子量为9500（9.5K）和13000（13 K）的两个稳定片段。除去NaDodS 04后，通过Bio-Rex 70色谱法在6 M尿素中拆分两个片段。从每个片段和溴化氰裂解产物中释放的末端氨基酸的分析表明，9.5 K片段是CRP中的氨基近端，而13 K片段是羧基近端。氨基酸组成的显著特征是CRP亚基中存在的两个寡核苷酸的13 K片段中相对高量的精氨酸和蛋氨酸以及9.5K片段中的保留。在8 M尿素等电聚焦后，9.5 K片段、22.5 K CRP和13 K片段分别迁移至pH 5.5、8.3和10.3。CRP是一种cAMP刺激的DNA结合蛋白，在cAMP存在和不存在的情况下，13 K片段与DNA结合。9.5K片段缔合形成二聚体和十聚体。这些数据与一个模型是一致的，在该模型中，DNA结合结构域存在于CRP的羧基近端区域，而氨基近端区域包含亚基-亚基相互作用位点和大部分cAMP结合结构域。环腺苷酸受体蛋白（CRP）* 1是大肠杆菌基因表达的正调控因子。在cAMP存在的情况下，CRP结合到分解产物抑制操纵子的启动子位点内的位点，使RNA聚合酶能够形成开放启动子复合物，这是进入细胞的先决条件。
Hiroji Aiba* andJoseph S. Krakow* abstract: The cyclic AMP receptor protein (CRP) is a positive and negative regulatory protein for gene expression in Escherichia coli. The protein has been cleaved proteolyt-ically to determine the relation between CRP structure and function. In thepresence of sodium dodecyl sulfate (Na-DodS04), chymotrypsin dissects CRP into two stable frag-ments of molecular weight 9500 (9.5 K) and 13 000 (13K). After removal of NaDodS04, the two fragments are resolved by Bio-Rex 70 chromatography in 6 M urea. Analyses of the terminal amino acids released from each fragment and cyanogen bromide cleavage products indicate that the 9.5 K fragment is amino proximal in CRP while the 13K fragment is carboxyl proximal. Notable features of amino acid com-position are the relatively high amount of arginine and me-thionine in the 13K fragment and theretention in the 9.5 K fragment of the two tryptophans present in the CRP subunit. Following isoelectric focusing in 8 M urea, the 9.5 K fragment, 22.5 K CRP, and 13Kfragment migrate to pH 5.5, 8.3, and 10.3, respectively. While CRP is a cAMP-stimulated DNA binding protein, the 13Kfragment bindsto DNA in the presence and absence of cAMP. The 9.5 K fragment associates to form dimersand decamers. These data are consonant with a model in which the DNA bindingdomain is present in the carboxyl proximal region of CRP while the amino proximal region contains the subunit-subunit interaction sites andmuch of the cAMP bindingdomain. e cyclic AMP receptor protein (CRP)* 1 is a positive reg-ulatory factor for gene expression in Escherichia coli. In the presence of cAMP, CRP binds to sites within the promoter loci of catabolite-repressible operons, enabling RNA polym-erase to form the open promoter complex prerequisite to in-