کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1946175 1053292 2006 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Investigation of the interaction of pig muscle lactate dehydrogenase with acidic phospholipids at low pH
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Investigation of the interaction of pig muscle lactate dehydrogenase with acidic phospholipids at low pH
چکیده انگلیسی

Interaction of pig muscle lactate dehydrogenase (LDH) with acidic phospholipids is strongly dependent on pH and is most efficient at pH values <6.5. The interaction is ionic strength sensitive and is not observed when bilayer structures are disrupted by detergents. Bilayers made of phosphatidylcholine (PC) do not bind the enzyme. The LDH interaction with mixed composition bilayers phosphatidylserine/phosphatidylcholine (PS/PC) and cardiolipin/phosphatidylcholine (CL/PC) leads to dramatic changes in the specific activity of the enzyme above a threshold of acidic phospholipid concentration likely when a necessary surface charge density is achieved. The threshold is dependent on the kind of phospholipid. Cardiolipin (CL) is much more effective compared to phosphatidylserine, which is explained as an effect of availability of both phosphate groups in a CL molecule for interaction with the enzyme. A requirement of more than one binding point on the enzyme molecule for the modification of the specific activity is postulated and discussed. Changes in CD spectra induced by the presence of CL and PS vesicles evidence modification of the conformational state of the protein molecules. In vivo qualitative as well as quantitative phospholipid composition of membrane binding sites for LDH molecules would be crucial for the yield of the binding and its consequences for the enzyme activity in the conditions of lowered pH.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Biomembranes - Volume 1758, Issue 2, February 2006, Pages 133–144
نویسندگان
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