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A Kindelis

Publications and source records attributed to A Kindelis.

5 recordsLinked to original sources

HMG proteins (1 + 2) form beaded structures when complexed with closed circular DNA.

Structures bearing a resemblance to nucleosomes can be assembled by incubating calf thymus High Mobility Group proteins (1 + 2) with closed circular DNA. These HMG proteins are capable of forming beads and inducing superhelicity when bound to DNA. However, they do not protect from nuclease digestion the discrete DNA fragments characteristic of nucleosomes. The relationship between HMGs (1 + 2) and the "primitive" histone-like DNA-packaging proteins from prokaryotes and mitochondria is discussed.

Animals↗

Thermal denaturation of the DNA-ethidium complex. Redistribution of the intercalated dye during melting.

The temperature dependence of the circular dichroism of the DNA-ethidium bromide complex at elevated temperatures provides evidence that the optical activity of the complex near 307 nm originates from interactions between intercalated dye molecules while the optical activity near 515 nm results from singly intercalated ethidium bromide molecules. The behavior of the circular dichroism of the complex at elevated temperatures also explains the higher ellipticities near 307 nm which characterize complexes formed between ethidium bromide and denaturated DNA. Finally the circular dichroism data indicate that the melting of the complex takes place in a stepwise manner with some DNA regions, probably AT-rich regions, dissociating first. The implications of these findings regarding the inhibiting effect of ethidium bromide on the function of DNA polymerase are examined.

Animals↗