1d9p
SOLUTION STRUCTURE OF CECROPIN A(1-8)-MAGAININ 2(1-12) HYBRID PEPTIDE ANALOGUE(P4)
OverviewOverview
In order to elucidate the structure-antibiotic activity relationships of the peptides, the three-dimensional structures of two hybrid peptides, CA(1-8) - MA(1-12) and CA(1-8) - ME(1-12) in trifluoroethanol-containing aqueous solution were investigated by NMR spectroscopy. Both CA(1-8) - MA(1-12) and CA(1-8) - ME(1-12) have strong antibacterial activity but only CA(1-8) - ME(1-12) has hemolytic activity against human erythrocytes. CA(1-8) - MA(1-12) has a hydrophobic 310-helix of only two turns combined with one short helix in the N-terminus with a flexible hinge section in between. CA(1-8) - MA(1-12) has a severely bent structure in the middle of the peptide. These structural features as well as the low hydrophobicity of CA(1-8) - MA(1-12) seem to be crucial for the selective lysis against the membrane of prokaryotic cells. CA(1-8) - ME(1-12) has an alpha-helical structure of about three turns in the melittin domain and a flexible structure with one turn in the cecropin domain connected with a flexible hinge section in between, and these might be the structural features required for membrane disruption against prokaryotic and eukaryotic cells. The central hinge region (Gly9-Ile10-Gly11) in an amphipathic antibacterial peptide is considered to play an important role in providing the conformational flexibility required for ion channel formation of the C-terminal hydrophobic alpha-helix on cell membrane.
About this StructureAbout this Structure
1D9P is a Single protein structure of sequence from Xenopus laevis + hyalophora cecropia. Full crystallographic information is available from OCA.
ReferenceReference
NMR structural characterization of cecropin A(1-8) - magainin 2(1-12) and cecropin A (1-8) - melittin (1-12) hybrid peptides., Oh D, Shin SY, Kang JH, Hahm KS, Kim KL, Kim Y, J Pept Res. 1999 May;53(5):578-89. PMID:10424354 Page seeded by OCA on Fri May 2 13:36:27 2008