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Quasi-Two-Dimensional Smectic States of DNA Molecules Intercalated between Lipid Membranes in Multi-Lamellar Phases

Published online by Cambridge University Press:  15 February 2011

Leonardo Golubović ,
Dorel Moldovan  and
Mirjana Golubović
Leonardo Golubović
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506
Dorel Moldovan
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506
Mirjana Golubović
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506
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Abstract

We study fluctuations of DNA-cationic lipid complexes in their lamellar membrane phases with DNA intercalated between lipid membranes. We theoretically elucidate this novel state of matter by characterizing it as the very first realization of a decoupled (unregistered) phase of strongly fluctuating 2-d smectic manifolds weakly interacting across membranes. Due to couplings between adjacent 2-d smectic Lx, × Ly planes, the experimentally observed ordinary 2-d smectic behavior [Salditt et al., Phys. Rev. Lett. 79, 2582 (1997)] of DNA in-plane undulations, with , must cross over, at the longest scales, to a novel fluctuation behavior, with < u2 > ˜ (logLy )2 ˜ (logLx.)2.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 489: Symposium K – Materials Science of the Cell , 1997 , 13
Copyright
Copyright © Materials Research Society 1998

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References

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