van der Ende A, Langeveld S A, Van Arkel G A, Weisbeek P J
Eur J Biochem. 1982 May 17;124(2):245-52. doi: 10.1111/j.1432-1033.1982.tb06584.x.
The binding of the bacteriophage phi X 174-coded A and A* proteins to single-stranded (ssDNA) and double-stranded (dsDNA ) phi X DNA was studied by electron microscopy. The interaction of the A* protein with ssDNA and dsDNA was also studied by sedimentation velocity centrifugation. It was shown that the binding of the A and A* proteins to ssDNA occurs in a non-cooperative manner and requires no or very little sequence specificity under the conditions used here. Both protein-ssDNA complexes have the same compact structure caused by intrastrand cross-linking through the interaction of protein molecules with separate parts of the ssDNA molecule. The A protein does not bind to phi X dsDNA in the absence of divalent cations. The A* protein does bind to dsDNA, although it has a strong preference for binding to ssDNA. The structure of the A* protein-dsDNA complexes is different from that of the A* protein-ssDNA complexes, as the former have a rosette-like structure caused by protein-protein interactions. High ionic strengths favour the formation of large condensed aggregates.
通过电子显微镜研究了噬菌体φX 174编码的A蛋白和A蛋白与单链（ssDNA）和双链（dsDNA）φX DNA的结合。还通过沉降速度离心法研究了A蛋白与ssDNA和dsDNA的相互作用。结果表明，A蛋白和A蛋白与ssDNA的结合以非协同方式发生，在此处使用的条件下不需要或只需要很少的序列特异性。两种蛋白质-ssDNA复合物具有相同的紧密结构，这是通过蛋白质分子与ssDNA分子的不同部分相互作用而发生链内交联导致的。在没有二价阳离子的情况下，A蛋白不与φX dsDNA结合。A蛋白确实能与dsDNA结合，尽管它强烈倾向于与ssDNA结合。A蛋白-dsDNA复合物的结构与A蛋白-ssDNA复合物的结构不同，因为前者具有由蛋白质-蛋白质相互作用导致的玫瑰花结样结构。高离子强度有利于形成大的凝聚聚集体。
