The Curvature Induction of Surface-Bound Antimicrobial Peptides Piscidin 1 and Piscidin 3 Varies with Lipid Chain Length

The Curvature Induction of Surface-Bound Antimicrobial Peptides Piscidin 1 and Piscidin 3 Varies... The initial steps of membrane disruption by antimicrobial peptides (AMPs) involve binding to bacterial membranes in a surface-bound (S) orientation. To evaluate the effects of lipid composition on the S state, molecular dynamics simulations of the AMPs piscidin 1 (p1) and piscidin 3 (p3) were carried out in four different bilayers: 3:1 DMPC/DMPG, 3:1 POPC/POPG, 1:1 POPE/POPG, and 4:1 POPC/cholesterol. In all cases, the addition of 1:40 piscidin caused thinning of the bilayer, though thinning was least for DMPC/DMPG. The peptides also insert most deeply into DMPC/DMPG, spanning the region from the bilayer midplane to the headgroups, and thereby only mildly disrupting the acyl chains. In contrast, the peptides insert less deeply in the palmitoyl-oleoyl containing membranes, do not reach the midplane, and substantially disrupt the chains, i.e., the neighboring acyl chains bend under the peptide, forming a basket-like conformation. Curvature free energy derivatives calculated from the simulation pressure profiles reveal that the peptides generate positive curvature in membranes with palmitoyl and oleoyl chains but negative curvature in those with myristoyl chains. Curvature inductions predicted with a continuum elastic model follow the same trends, though the effect is weaker, and a small negative curvature induction is obtained in POPC/POPG. These results do not directly speak to the relative stability of the inserted (I) states or ease of pore formation, which requires the free energy pathway between the S and I states. Nevertheless, they do highlight the importance of lipid composition and acyl chain packing. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Membrane Biology Springer Journals

The Curvature Induction of Surface-Bound Antimicrobial Peptides Piscidin 1 and Piscidin 3 Varies with Lipid Chain Length

Loading next page...
 
/lp/springer_journal/the-curvature-induction-of-surface-bound-antimicrobial-peptides-9wAe8m9QzJ
Publisher
Springer US
Copyright
Copyright © 2014 by Springer Science+Business Media New York (Outside the USA)
Subject
Life Sciences; Biochemistry, general; Human Physiology
ISSN
0022-2631
eISSN
1432-1424
D.O.I.
10.1007/s00232-014-9733-1
Publisher site
See Article on Publisher Site

Abstract

The initial steps of membrane disruption by antimicrobial peptides (AMPs) involve binding to bacterial membranes in a surface-bound (S) orientation. To evaluate the effects of lipid composition on the S state, molecular dynamics simulations of the AMPs piscidin 1 (p1) and piscidin 3 (p3) were carried out in four different bilayers: 3:1 DMPC/DMPG, 3:1 POPC/POPG, 1:1 POPE/POPG, and 4:1 POPC/cholesterol. In all cases, the addition of 1:40 piscidin caused thinning of the bilayer, though thinning was least for DMPC/DMPG. The peptides also insert most deeply into DMPC/DMPG, spanning the region from the bilayer midplane to the headgroups, and thereby only mildly disrupting the acyl chains. In contrast, the peptides insert less deeply in the palmitoyl-oleoyl containing membranes, do not reach the midplane, and substantially disrupt the chains, i.e., the neighboring acyl chains bend under the peptide, forming a basket-like conformation. Curvature free energy derivatives calculated from the simulation pressure profiles reveal that the peptides generate positive curvature in membranes with palmitoyl and oleoyl chains but negative curvature in those with myristoyl chains. Curvature inductions predicted with a continuum elastic model follow the same trends, though the effect is weaker, and a small negative curvature induction is obtained in POPC/POPG. These results do not directly speak to the relative stability of the inserted (I) states or ease of pore formation, which requires the free energy pathway between the S and I states. Nevertheless, they do highlight the importance of lipid composition and acyl chain packing.

Journal

The Journal of Membrane BiologySpringer Journals

Published: Oct 8, 2014

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off