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PubMed · 10550688

Double-strand DNA hydrolysis by dilanthanide complexes.

M E Branum·L Que
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Abstract

Although there has been progress in developing artificial hydrolytic DNA cleaving agents, none of these has been shown to carry out the double-strand hydrolysis of DNA. We demonstrate that La(III) or Ce(IV) combined with the ligand 1,3-diamino-2-hydroxypropane-N,N,N', N'-tetraacetate (HPTA) in a 2 : 1 ratio can efficiently cleave supercoiled plasmid DNA at 55 degrees C within a 3-h period. Analysis of end-labeled restriction fragments cleaved by these complexes reveals 3'- and 5'-ends consistent with a hydrolytic mechanism. Unlike for other polydentate carboxylate complexes, plasmid DNA cleavage by La(2)(HPTA) or Ce(2)(HPTA) affords a significant amount of linear DNA with a considerable fraction of the supercoiled form still remaining. This result implies that La(2)(HPTA) and Ce(2)(HPTA) can carry out double-strand cleavage of plasmid DNA. La(2)(HPTA) and Ce(2)(HPTA) represent the first metal complexes demonstrated to be capable of double-strand hydrolytic cleavage of plasmid DNA.

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DNADNA, SuperhelicalEscherichia coliHydrolysisMetals, Rare EarthPlasmidsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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M E Branum, L Que. 1999. Double-strand DNA hydrolysis by dilanthanide complexes.. https://doi.org/10.1007/s007750050382

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