Peptide membranes

Typically, the insertion induces sharp variation of the membrane profile at the distances 0.5-1.0nm from the membrane-peptide interface [79-82]. The steepness of this perturbation indicates that the short-A, behavior of membrane moduli must be important in the estimates of the elastic energy. In addition, a peptide inserted in a membrane almost certainly perturbs the membrane s elastic moduli in the immediate vicinity of the inclusion. Both these effects, membrane nonlocality and nonuniform modification of elastic properties by insertions, might play an important role in resolving the contradiction between the local calculations [80] and the experimental data for the mean lifetime of a gramicidin channel [81,109,110]. ... 

Daniel, H. Function and molecular structure of brush border membrane peptide/H+ symporters. J. Membr. 

Hong M (2007) Structure, topology, and dynamics of membrane peptides and proteins from solid-state NMR spectroscopy. J Phys Chem B 111 10340-10351... 

Marcotte I, Auger M (2005) Bicelles as model membranes for solid- and solution-state NMR studies of membrane peptides and proteins. Concept Magn Reson A 24A 17-37... 

Papo N, Shai Y (2003) Can we predict biological activity of antimicrobial peptides from their interactions with model phospholipid membranes Peptides 24 1693-1703... 

The structural analysis of membrane-associated peptides comprises two steps (a) the elucidation of the three-dimensional fold of the peptide and (b) the determination of the membrane-peptide interface. We will use our results gained for the 36 amino acid residue neuropeptide Y (NPY) [83] to demonstrate the approaches that can be used. NPY regulates important pharmacological functions such as blood pressure, food intake or memory retention and hence has been subject of many investigations (for a review see Ref. [84]). It targets the so-called Y receptors that belong to the class of seven transmembrane receptors coupled to G-proteins (GPCRs). 

The next three sections (Sections 7.7.1, 7.7.2, and 7.7.3) cover fluorescence spectroscopy, I15-18 infrared, and circular dichroism, three powerful approaches to characterize the structure and conformational considerations of synthetic peptides. Section 7.7.1 deals with the use of fluorophores and broad aspects of fluorescence spectroscopy to characterize conformational aspects of peptide structure. In a similar manner, Section 7.7.2 covers a broad aspect of the uses of infrared (IR) techniques to study peptide conformations 19-22 Many IR techniques are discussed, as are approaches for the study of specific peptidic structures including amyloid, p-turn, and membrane peptides. Finally, there is a section on circular dichroism (Section 7.7.3) that covers the major issues of concern for peptide synthetic chemists such as the assignments of a-helix, 310-helix, -sheets and P-turns, and polyproline helices 23-25 There is also a brief description of cyclic peptides. 

D. E. Warschawski, J. D. Gross and R. G. Griffin, Effects of membrane peptide dynamics on high-resolution magic-angle spinning NMR, J. Chim.-Phys. Phys. Biol., 1998, 95, 460-466. 

Nakanishi T, Ando E, Furuta M, Tsunasawa S, Nishimura O (2007) Direct on-membrane peptide mass fingerprinting with MALDI-MS of tyrosine-phosphorylated protein detected by immunostaining. J Chromatogr B 847 24-29. doi 10.1016/j.jchromb.2006.08.024... 

Alam MR, Johnson RC, Darlington DN, Hand TA, Mains RE, Eipper BA (1997) Kalirin, a cytosolic protein with spectrin-like and GDP/ GTP exchange factor-like domains that interacts with peptidylgly-cine alpha-amidating monooxygenase, an integral membrane peptide-processing enzyme. J Biol Chem 272 12667-12675. 

MAS has long been employed to obtain site-specific structural information in membrane proteins such as bacteriorhodopsin or rhodopsin (for recent reviews see, for example. Refs. 27,174). In addition, MAS-based solid-state NMR studies were also conducted using selectively labelled membrane peptides or peptides reconstimted into... 

JFig. 10 shows some of the simulations from the work for motions with different effective asymmetries. The experiment was applied to JH-13C dipolar couplings in phenylalanine, and a polymer (polycarbonate) as shown in Fig. 11 and was also demonstrated for a membrane peptide using 15N-JH dipolar couplings. 

Balasubramaniam, A., Sheriff, S., Riegel, D.F. Fischer, J.E. (1990) Characterization of neuropeptide Y binding sites in rat cardiac ventricular membranes. Peptides (1990) 11, 545-550. 

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