STOPPED-FLOW X-RAY-SCATTERING - THE DISSOCIATION OF ASPARTATE-TRANSCARBAMYLASE
STOPPED-FLOW X-RAY-SCATTERING - THE DISSOCIATION OF ASPARTATE-TRANSCARBAMYLASE
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DOI：
10.1073/pnas.77.7.4040
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发表时间：
1980-01-01
期刊：
影响因子：
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通讯作者：
BORDAS, J
中科院分区：
文献类型：
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作者：
MOODY, MF;VACHETTE, P;BORDAS, J
在存在和不存在过渡态类似物N-（膦酰基乙酰基）-L-天冬氨酸的情况下，使用停流和X射线散射技术的组合来研究天冬氨酸转氨甲酰酶（氨甲酰磷酸：L-天冬氨酸氨甲酰转移酶，EC 2.1.3.2）与2：1过量的对氯汞苯磺酸（基于反应位点计算比率）的解离。在10 mg蛋白质/ml下，散射曲线允许跟踪反应的一些细节，时间分辨率低至1 s。该曲线不仅显示了酶复合物的解离，而且还显示了亚基的形成。利用现有的设备，X射线散射可用于研究解离或再缔合反应，其时间分辨率为100 ms。
A combination of stopped-flow and X-ray scattering techniques was used to study the dissociation of aspartate transcarbamylase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2) with a 2:1 excess of p-chloromercuribenzenesulfonic acid (the ratio being calculated on a basis of reactive sites), in the presence and absence of the transition state analogue N-(phosphonacetyl)-L-aspartate. At 10 mg of protein/ml, the scattering curves allowed some details of the reaction to be followed with a time resolution down to 1 s. The curves showed not only the dissociation of the enzyme complex but also the formation of the subunits. With present facilities, X-ray scattering could be used to study dissociation or reassociation reactions with a time resolution of the order of 100 ms.