کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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2189193 | 1096202 | 2007 | 11 صفحه PDF | دانلود رایگان |
A knowledge of the structures of acyl chain loaded species of the acyl carrier protein (ACP) as used in fatty acid biosynthesis and a range of other metabolic events, is essential for a full understanding of the molecular recognition at the heart of these processes. To date the only crystal structure of an acylated species of ACP is that of a butyryl derivative of Escherichia coli ACP. We have now determined the structures of a family of acylated E. coli ACPs of varying acyl chain length. The acyl moiety is attached via a thioester bond to a phosphopantetheine linker that is in turn bound to a serine residue in ACP. The growing acyl chain can be accommodated within a central cavity in the ACP for transport during the elongation stages of lipid synthesis through changes in the conformation of a four α-helix bundle. The results not only clarify the means by which a substrate of varying size and complexity is transported in the cell but also suggest a mechanism by which interacting enzymes can recognize the loaded ACP through recognition of surface features including the conformation of the phosphopantetheine linker.
Journal: Journal of Molecular Biology - Volume 365, Issue 1, 5 January 2007, Pages 135–145