کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10798254 | 1053309 | 2005 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Molecular associations and surface-active properties of short- and long-N-acyl chain ceramides
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
CMCN-hexanoylsphingosineAmphiphileN-acetylsphingosineDEPEMLV1-anilinonaphthalene-8-sulfonic acid - 1-anilinonaftalene-8-sulfonic acidDMSO - DMSOmultilamellar vesicles - vesicles multilamellarRh-PE - با Rh-PELipid monolayer - تک لایه لیپیدیdielaidoylphosphatidylethanolamine - دیایدیدیل فسفاتیدیلتانولامینDimethylsulfoxide - دیمتیل سولفواکسیدANS - سالceramide - سرامیدSurfactant - سورفکتانتCritical micellar concentration - غلظت میکرولیکی بحرانیphosphatidylcholine - فسفاتیدیل کولینSurface pressure - فشار سطحDetergent - مواد شویندهMicelle - میسل
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شیمی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The behaviour of N-hexadecanoylsphingosine (Cer16), N-hexanoylsphingosine (Cer6) and N-acetylsphingosine (Cer2) in aqueous media and in lipid-water systems, monolayers and bilayers has been comparatively examined using Langmuir balance and fluorescence techniques. Cer16 behaves as an insoluble non-swelling amphiphile, not partitioning into the air-water interface, thus not modifying the surface pressure of the aqueous solutions into which it is included. By contrast both Cer6 and Cer2 behave as soluble amphiphiles, up to approx. 100 μM. At low concentrations, they become oriented at the air-water interface, increasing surface pressure in a dose-dependent way up to ca. 5 μM bulk concentration. At higher concentrations, the excess ceramide forms micelles, critical micellar concentrations of both Cer6 and Cer2 being in the 5-6 μM range. When the air-water interface is occupied by a phospholipid, 6Cer2 and Cer6 become inserted in the phospholipid monolayer, causing a further increase in surface pressure. This increase is dose dependent, and reaches a plateau at ca. 2 μM ceramide bulk concentration. Both Cer2 and Cer6 become inserted in phospholipid monolayers with initial surface pressures of up to 43 and 46 mN mâ1, respectively, which ensures their capacity to become inserted into cell membranes whose monolayers are estimated to support a surface pressure of about 30 mN mâ1. Both Cer2 and Cer6, but not Cer16, had detergent-like properties, such as giving rise to phospholipid-ceramide mixed micelles, when added to phospholipid monolayers or bilayers. The short-chain ceramides form large aggregates and precipitate at concentrations above approx. 100 μM. These results are relevant in cell physiology studies in which short- and long-chain ceramides are sometimes used as equivalent molecules, in spite of their different biophysical behaviour.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Biomembranes - Volume 1711, Issue 1, 1 June 2005, Pages 12-19
Journal: Biochimica et Biophysica Acta (BBA) - Biomembranes - Volume 1711, Issue 1, 1 June 2005, Pages 12-19
نویسندگان
Jesús Sot, Félix M. Goñi, Alicia Alonso,