Polyethylene glycol and divalent salt-induced DNA reentrant condensation revealed by single molecule measurements.
Soft Matter
; 11(19): 3927-35, 2015 May 21.
Article
en En
| MEDLINE
| ID: mdl-25871460
ABSTRACT
In this study, we investigated the DNA condensation induced by polyethylene glycol (PEG) with different molecular weights (PEG 600 and PEG 6000) in the presence of NaCl or MgCl2 by using magnetic tweezers (MT) and atomic force microscopy (AFM). The MT measurements show that with increasing NaCl concentration, the critical condensation force in the PEG 600-DNA or PEG 6000-DNA system increased approximately linearly. PEG 6000 solution has a larger critical force than PEG 600 solution at a given NaCl concentration. In comparison, a parabolic trend of the critical condensation force was observed with increasing MgCl2 concentration, indicating that DNA undergoes a reentrant condensation. The AFM results show that the morphologies of the compacted DNA-PEG complexes depended on the salt concentration and were consistent with the MT results.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ADN
/
Cloruro de Sodio
/
Cloruro de Magnesio
/
Microscopía de Fuerza Atómica
Idioma:
En
Revista:
Soft Matter
Año:
2015
Tipo del documento:
Article
País de afiliación:
China