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Indian Journal of Chemistry -Section B (IJC-B) >
IJC-B Vol.48B [2009] >
IJC-B Vol.48B(09) [September 2009] >
| Title: | Synthesis and conformation of a hexapeptide fragment (3-8) of SPF peptide by NMR and restrained molecular dynamics |
| Authors: | Sunilkumar, P N
Sadasivan, C
Devaky, K S
Haridas, M |
| Keywords: | Seminalplasmin
SPF peptide
peptide conformation
NMR
restrained molecular dynamics |
| Issue Date: | Sep-2009 |
| Publisher: | CSIR |
| Abstract: |
Seminalplasmin (SPLN)
is a 47-residue peptide from bovine seminal plasma which shows broad spectrum
antimicrobial activity but no hemolytic activity and it lyses dividing
mammalian cells, but not resting cells. It is reported that the 28-40 segment
of SPLN, designated as SPF, is the most hydrophobic stretch of SPLN and
primarily responsible for the membrane-perturbing activity of SPLN. The SPF
peptide has a helical structure as shown by CD analysis. Molecular dynamics studies show that SPF peptide
has two helical segments, regions
Leu4-Phe7 and Lys10-Ile12. The helical structure makes it biologically
active. The hexapeptide studied presently, Leu-Leu-Glu-Thr-Phe-Leu, forms the
3-8 region of SPF. NMR analysis shows that the hexapeptide
Leu-Leu-Glu-Thr-Phe-Leu has an extended backbone conformation. Molecular
dynamics studies show that the electrostatic attraction between opposite
charges at 2nd and 5th positions stabilises the helical
structure of SPF peptide. The lack of 2nd residue (Lys)
in the experimental 3-8 peptide fragment of SPF explains its extended
structure. This information has led to the conclusion that the regions other
than this hexapeptide motif are essential to maintain the helical structure of
SPF peptide |
| Page(s): | 1294-1298 |
| Source: | IJC-B Vol.48B(09) [September 2009]
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