Abstract:
:Over a large range of salt and spermidine concentrations, short DNA fragments precipitated by spermidine (a polyamine) sediment in a pellet from a dilute isotropic supernatant. We report here that the DNA-condensed phase consists of a cholesteric liquid crystal in equilibrium with a more concentrated phase. These results are discussed according to Flory's theory for the ordering of rigid polymers. The liquid crystal described here corresponds to an ordering in the presence of attractive interactions, in contrast with classical liquid crystalline DNA. Polyamines are often used in vitro to study the functional properties of DNA. We suggest that the existence of a liquid crystalline state in spermidine-condensed DNA is relevant to these studies.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Sikorav JL,Pelta J,Livolant Fdoi
10.1016/S0006-3495(94)80640-Xsubject
Has Abstractpub_date
1994-10-01 00:00:00pages
1387-92issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(94)80640-Xjournal_volume
67pub_type
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