[Features of the structure of apolipoprotein A1 as an HDL and complexes with dimyristoylphosphatidylcholine. A method for low temperature ESR-spectroscopy].
Apolipoprotein A1 (apoA1) was labelled with the excess of 2,2,6,6-tetramethylpiperidinyl-N-oxyl-4-(2,4-dichloro-1,3,5- triazinyl-6)-amine at pH 9.8. The products, containing 7.2 (+/- 1) paramagnetic labels per 1 molecule of apoA1, showed spin-spin and dipole-dipole exchange interactions. The ESR spectra of the spin labelled A1 (at 77K) had d1/d values 0.76 (at pH 7.4), 0.59 (in 3 M NaCl), 0.55 (in 3 M guanidinium hydrochloride), 0.44 (in 40% 2-chloroethanol). Micellar complexes of spin labelled apoA1/DMPC (1 : 20 mol/mol and 1 : 190 mol/mol) and HDL containing spin labelled apoA1 were prepared. Comparison of ESR spectra at 77 K showed that apoA1 structure varies in the complexes with different stoichiometry and in spin labelled HDL. These data show the importance of hydrophobic protein-protein interactions for the structure of HDL and synthetic complexes of apoA1 with phosphatidyl choline.
Medvedeva
P V
PV
Misharin
A Iu
AIu
D016632:Apolipoprotein A-I; D001054:Apolipoproteins A / Q000737:chemistry*; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008854:Microscopy, Electron; D013696:Temperature
D016632:Apolipoprotein A-I; D001054:Apolipoproteins A; D004134:Dimyristoylphosphatidylcholine
Osobennosti struktury apolipoproteina A1 v sostave LVP i kompleksov s dimiristoilfosfatidilkholinom. Issledovanie metodom nizkotemperaturnoĭ EPR-spektroskopii.