Understanding of the regulatory mechanism on the activity of chloroplast-type ATP synthase by X-ray crystallography

叶绿体型三磷酸腺苷合成酶伽马亚基上的插入区域强烈影响内源性epsilon亚基的抑制效应(epsilon抑制)。为了了解插入区域和epsilon亚单位之间的关系，我们试图分解叶绿体型ATP合成酶亚复合体(α3β3γ1 epsilon 1)的结构。虽然我们还不能获得高分辨率的晶体，但我们成功地获得了稳定的亚络合突变体用于结晶，并获得了一些晶体。我们还研究了伽马亚基上插入区域对β亚基上ATPase活性的影响，因为这两个部分彼此相距很远。然后我们确定了伽马亚基中两个中心α螺旋的构象变化，它与β亚基上的催化位点相互作用，是阅读插入区域的调控效应所必需的。

Inserted region on the gamma subunit of chloroplast type ATP synthase strongly affect to the inhibitory effect of endogenous epsilon subunit (epsilon inhibition). To understand the relationship between the inserted region and the epsilon subunit, we try to dissolve structure of sub-complex of chloroplast type ATP synthase (alpha3beta3gamma1epsilon1). Though we could not yet get crystal in high resolution, we succeeded to make stable sub-complex mutant for crystallization and could get some crystal.We also investigated an affect of the inserted region on the gamma subunit to the ATPase activity on the beta subunit because these two parts exist far form each other. We then identified a conformational change of two central alpha helices in gamma subunit which is interact with catalytic sites on the beta subunit is necessary to read regulatory effect of the inserted region.