Interaction of berberine chloride with deoxyribonucleic acids: evidence for base and sequence specificity.
Indian J Biochem Biophys
;
1989 Aug; 26(4): 201-8
Artigo
em Inglês
| IMSEAR
| ID: sea-27132
ABSTRACT
The interaction of berberine chloride with natural and synthetic DNAs of differing base composition and sequences was followed by various spectroscopic and viscometric studies. The binding of berberine chloride was characterized by hypochromism and bathochromism in the absorption bands, enhancement of fluorescence intensity, stabilization against thermal denaturation, perturbations in the circular dichroic spectrum, increase in the contour length of sonicated rod-like DNA and induction of unwinding-rewinding process of covalently closed superhelical DNA, depending on the base composition and sequences of base pairs. Binding parameters determined from absorbance and fluorescence titration by Scatchard analysis, according to an excluded-site model, indicated a very high specificity of berberine to AT-rich DNAs and alternate AT polymer. Fluorescence quantum yield was maximum for the complexes with AT-rich DNAs and alternate AT polymer. Taken together, these results suggest that berberine chloride exhibits considerable specificity towards alternating AT polymer and binds to AT-rich DNAs by a mechanism of classical intercalation.
Texto completo:
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Índice:
IMSEAR (Sudeste Asiático)
Assunto principal:
Polidesoxirribonucleotídeos
/
Berberina
/
Alcaloides de Berberina
/
DNA Bacteriano
/
Química
/
Fenômenos Químicos
Idioma:
Inglês
Revista:
Indian J Biochem Biophys
Ano de publicação:
1989
Tipo de documento:
Artigo
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