Interaction between human apolipoprotein A-Ⅰ and phosphatidylcholine vesicles = 인간의 Apolipoprotein A-Ⅰ 과 phosphatidylcholine vesicle 과의 상호 작용

The interactions of human apolipoprotein A-I (apo A-I0 with dipalmitoylphosphatidylcholine (DPPC) vesicles in the vesicular complex at low protein concentration and in the micellar complex at high protein concentration are compared. The C-terminal segment of this protein with relative molecular weight (Mr) of about 11,000 is protected from the trypsin treatment in the apo A-I-vesicle complexes. A segment within the sequence from Leu-189 to Arg-215 of apo A-I penetrates into the hydrophobic interior of the membrane according to the hydrophobic labeling experiment using 3-(trifluoromethyl)-3-(m-[$^{125}I$]iodophenyl)diazirine([$^{125}I$]-TID). No appreciable stretch of apo A-I in the micellar complex is found to be protected from the tryptic digestion. This indicates that the apo A-I interactions with lipid bilayer in vesicular and micellar forms are different. The binding equilibrium of apo A-I with DPPC vesicles at low protein concentration, as revealed by hydrophobic labeling study of the bilayer-penetrating segment, is reached in about one hour, while the formation of micellar complexes at high protein concentration takes about 24 h at 42$^\circ$C. The time-dependent labeling studies with photoreactive phosphatidylcholine (PC) at high apo A-I concentration suggest an initial interaction with head group region of the bilayer followed by the interaction with the tail ends of the acyl chain of the lipid. A possible mode of micellization process is discussed. hydroxylamine treated apo A-I without the C-terminal region is also found to induce micellization of DPPC vesicles.
Advisors
Kim, Hyoung-Manresearcher김형만researcher
Publisher
한국과학기술원
Issue Date
1989
Identifier
61319/325007 / 000845144
Language
eng
Description

학위논문(박사) - 한국과학기술원 : 생물공학과, 1989.8, [ x, 127 p. ]

URI
http://hdl.handle.net/10203/27280
Link
http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=61319&flag=t
Appears in Collection
BS-Theses_Ph.D.(박사논문)
Files in This Item
There are no files associated with this item.
  • Hit : 52
  • Download : 0
  • Cited 0 times in thomson ci

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0