The interaction with phospholipid bilayers of two synthetic peptides with
sequences corresponding to a segment next to the native N-terminus and
an internal region of the E2 structural hepatitis G virus (HGV⁄GBV-C)
protein [E2(7–26) and E2(279–298), respectively] has been characterized.
Both peptides are water soluble but associate spontaneously with bilayers,
showing higher affinity for anionic than zwitterionic membranes.
Vitamin E is an important topic because many benefits and some risks have
been attributed to it when used as a nutritional supplement. Moreover, there
has been considerable progress in the basic science of this vitamin in recent
years. This volume reviews recent aspects of the biochemistry and molecular
biology of this vitamin, associated macromolecules, metabolism of the
vitamin and its derivatives, and its many roles in health and disease. The
various contributions comprising this volume are listed here in the order in
which they are presented in the volume....
The coat proteins of filamentous phage are first synthesized as transmem-brane proteins and then assembled onto the extruding viral particles. We
investigated the transmembrane conformation of the Pseudomonas aerugi-nosa Pf3 phage coat protein using proton-decoupled
solid-state NMR spectroscopy.
The activity of outer membrane phospholipase A (OMPLA) is regulated by reversible dimerization. However, native OMPLA reconstituted in phospholipid vesicles was found to be present as a dimer but nevertheless inactive. To investigate the importance of dimerization for control of OMPLA activity, a covalent OMPLA dimer was constructed and its properties were compared to native OMPLA both in a micellar detergent and after reconstitution in a phospholipid bilayer.
2-Aminoethoxydiphenyl Borate (2-APB) has been extensively used recently as a membrane permeable modulator of inositol-1,4,5-trisphosphate-sensitive Ca2+ channels and store-operated Ca2+ entry. Here, we report that 2-APB is also an inhibitor of sarco/endoplasmic reticulum Ca2+ATPase (SERCA) Ca2+ pumps, and additionally increases ion leakage across the phospholipid bilayer. Therefore, we advise caution in the interpretation of results when used in Ca2+ signalling experiments.
Depth of bilayer penetration and effects on lipid mobility
conferred by themembrane-active peptidesmagainin, melit-tin, and a hydrophobic helical sequence KKA(LA)7KK
(denoted KAL), were investigated by colorimetric and
time-resolved fluorescence techniques in biomimetic phos-pholipid/poly(diacetylene)vesicles. The experiments dem-onstrated that the extent of bilayer permeation and peptide
localization within the membrane was dependent upon the
bilayer composition, and that distinct dynamic modifica-tions were induced by each peptide within the head-group
environment of the phospholipids....
Wehave examined the effectsof three ring-sizeanalogsof the
cyclicb-sheet antimicrobial peptidegramicidinS (GS) on the
thermotropic phase behavior and permeability of phos-pholipid model membranes and on the growth of the cell
wall-less Gram-positive bacteriaAcholeplasma laidlawiiB.
These three analogs have ring sizes of 10 (GS10), 12 (GS12)
or 14 (GS14) amino acids, respectively.
Hemolytic Anemias Due to Abnormalities of the MembraneCytoskeleton Complex
The detailed architecture of the red cell membrane is complex, but its basic design is relatively simple (Fig. 101-2). The lipid bilayer, which incorporates phospholipids and cholesterol, is spanned by a number of proteins that have their hydrophobic transmembrane domains embedded in the membrane. Most of these proteins have hydrophilic domains extending toward both the outside and the inside of the cell.
Protein sorting and assembly in membrane biogenesis and function involves
the creation of ordered domains of lipids known as membrane rafts. The
rafts are comprised of all the major classes of lipids, including glycero-phospholipids, sphingolipids and sterol. Cholesterol is known to interact
with sphingomyelin to form a liquid-ordered bilayer phase.