Photoaffinity labeling of the recBCD enzyme of Escherichia coli with 8-azidoadenosine 5'-triphosphate.
Photoaffinity labeling of the recBCD enzyme of Escherichia coli with 8-azidoadenosine 5'-triphosphate.
复制标题
使用 8-叠氮腺苷 5-三磷酸对大肠杆菌的 recBCD 酶进行光亲和标记。
DOI：
10.1016/s0021-9258(18)48044-1
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
I. Lehman
中科院分区：
文献类型：
--
作者：
D. Julin;I. Lehman
来自大肠杆菌的recBCD酶（核酸外切酶V）的recB和recD亚基用ATP光亲和类似物[α-32 P]8-叠氮基-ATP共价光标记。根据以下标准，标记对ATP结合位点具有特异性。在recD和recB亚基的解离常数分别为30和120 μ M的高8-叠氮基-ATP浓度下发生饱和; ATP强烈抑制光标记; 8-叠氮基-ATP被recBCD酶水解并支持其双链DNA核酸外切酶活性;标记主要限于通过胰蛋白酶消化光标记的全酶获得的两种肽;一种来源于recB亚基，另一种来源于recD亚基。
The recB and recD subunits of the recBCD enzyme (exonuclease V) from Escherichia coli were covalently photolabeled with the ATP photoaffinity analogue [alpha-32P]8-azido-ATP. The labeling was specific for ATP binding sites by the following criteria. Saturation occurs at high 8-azido-ATP concentrations with dissociation constants of 30 and 120 microM for the recD and recB subunits, respectively; ATP strongly inhibits the photolabeling; 8-azido-ATP is hydrolyzed by the recBCD enzyme and supports its double-stranded DNA exonuclease activity; and the label is largely confined to two peptides obtained by tryptic digestion of the photolabeled holoenzyme; one is derived from the recB subunit and the other from the recD subunit.