The
me
mbr
ane-bound st
ate of the gene 9
minor co
at protein of b
acterioph
age M13 w
as studiedin v
arious
me
mbr
ane-
mi
micking syste
ms, including org
anic solvents, detergent
micelles,
and phospholipidbil
ayers. For this purpose we deter
mined the confor
mation
al
and
aggreg
ation
al properties of the che
mic
allysynthesized protein by CD, FTIR,
and HPSEC. The protein
appe
ars to be in
a mono
meric or s
malloligo
meric
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al st
ate in TFE but
adopts
a mixture of
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al
and r
ando
m structure
after subsequentin
corpor
ation into SDS or DOPG. When solubilized by sodiu
m chol
ate, however, the protein undergoes
a tr
ansition in ti
me into l
arge
aggreg
ates, which cont
ain
mainly
![](/i<font color=)
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middle">-sheet confor
mation. The r
ate of this
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middle">-poly
meriz
ation process w
as decre
ased
at lower te
mper
ature
and higher concentr
ations of sodiu
m chol
ate.This
aggreg
ation w
as reversed only upon
addition of high concentr
ations of the strong detergent SDS. Byreconstitution of the chol
ate-solubilized protein into DOPG, it w
as found th
at the st
ate of the protein,whether initi
ally
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al
mono
meric/oligo
meric or
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a2.gif" BORDER=0 ALIGN="
middle">-sheet
aggreg
ate, did not ch
ange. On the b
asis ofour results, we propose th
at the princip
al confor
mation
al st
ate of
me
mbr
ane-bound gene 9 protein in vivois
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al.