کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
612610 | 880702 | 2006 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A thermodynamic study of GPI-anchored and soluble form of alkaline phosphatase films at the air–water interface A thermodynamic study of GPI-anchored and soluble form of alkaline phosphatase films at the air–water interface](/preview/png/612610.png)
Glycosylphosphatidyl inositol (GPI) anchored proteins are localized and clustered on the outer layer of the plasma membranes forming microdomains. Among them, mammalian alkaline phosphatases (AP-GPI) are widely distributed enzymes. They can also exist as soluble proteins without anchor (APs). Using the Langmuir film technique, we study the thermodynamic properties of monolayers for both protein forms at the air–buffer interface. The enzymatic activity is maintained at the interface but the adsorption of the two forms of AP is very different. AP-GPI presents a higher surface activity and a larger molecular area than the soluble form. The molecular area deduced for high surface pressures suggests a different organization of the monolayers for these two forms. APs molecules seem to adsorb as a multilayer at the interface while AP-GPI appear to be orientated with the major axis parallel to the interface. This orientation allows the accessibility of AP-GPI enzymatic sites that are turned in direction of the subphase as in vivo where the active sites must be turned outside of the membrane.
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Journal: Journal of Colloid and Interface Science - Volume 301, Issue 2, 15 September 2006, Pages 493–502