幽門螺旋桿菌為厭氧性格蘭氏陰性菌，當進入人體胃部時能藉其鞭毛及螺旋狀的外型鑽入胃黏膜中，以躲避胃酸的侵蝕。感染幽門螺旋桿菌會造成胃及十二指腸的發炎及潰瘍，更嚴重有造成胃癌的可能。輔酶A在生物體中是重要的醯基攜帶者，它參予了多種生物代謝反應。合成輔酶A的步驟中包含了五個步驟，分別由五種酵素所催化，酵素磷酸泛酸醯基乙胺腺苷轉移酶 (phosphopantetheine adenylyltransferas, PPAT)為其中的第四個酵素，它能夠催化合成反應中的一個速率決定步驟，且最後生合成的輔酶A可以抑制其活性。PPAT在不同細菌中有很高的序列相似性，但是與人類中相同功能的酵素序列相似性不高，所以若是針對此酵素來發展抗菌藥物可能對於抑制幽門螺旋桿菌感染有很大的幫助。
針對輔酶A可以與PPAT結合，並且對整個輔酶A生合成的步驟產生負回饋的特性，我們將PPAT中數個能夠與輔酶A結合的殘基 (residue)突變為丙氨酸 (alanine)，藉以觀察輔酶A與PPAT是由什麼方式結合，以及辨別出在結合過程中較為重要的殘基，或許能夠幫助未來抗菌藥物的發展。
另一方面，先前實驗室的研究發現PPAT上兩個殘基的突變 (I4V/N76Y PPAT)會造成一個先前在PPAT相關研究中都未出現過的 domain-swapped結構，我們認為是由於第76個殘基天冬酰胺 (Asparagine)點突變為酪氨酸(Tyrosine)所致，並且也從結構上的結果證實。

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