[Effect of single-stranded and double-stranded breaks on the melting temperature of phage T2 DNA].
The effect of single- and double-stranded breaks in DNA phage T2, on the melting temperature of this DNA in the 0,05 M SSC solution, was investigated. The number of cleavages per 1000 nucleotide pairs varied in the range of 0 to 10. It is shown that single- and double-stranded breaks affect the melting temperature with approximately (within 20%) the same efficiency. The relationship between the melting temperature shift (delta Tm) and the number of cleavages is non-linear. The magnitude of the effect is characterized by delta Tm of 2 +/- 0.4 degrees C for the average inter-cleavage distance of 200 base pairs. It is shown that the observed melting curves are non-equilibrium ones, which is probably due to the fact that the effect of cleavages on the melting temperature is largely results from the complete and practically irreversible separation of strands.
D003090:Coliphages / Q000032:analysis*; D004277:DNA, Single-Stranded; D004279:DNA, Viral; D004926:Escherichia coli / Q000032:analysis; D007700:Kinetics; D009691:Nucleic Acid Denaturation; D013696:Temperature
D004277:DNA, Single-Stranded; D004279:DNA, Viral
Vliianie odnonitevykh i dvunitevykh razryvov na temperaturu plavleniia DNK faga T2.