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J C Dabrowiak

Publications and source records attributed to J C Dabrowiak.

56 records · Page 4Linked to original sources
PubMedDate not supplied

Chemically and photochemically initiated DNA cleavage by an insulin-mimetic bisperoxovanadium complex.

Chemically and photochemically induced cleavage of DNA by the insulin-mimetic compound NH4[VO(O2)2-(1,10-phenanthroline)], bpV(phen), have been studied. 51V NMR and absorption indicate that photoirradiation with low energy UV light of aqueous solutions containing bpV(phen) leads to the conversion of the compound to simple vanadates. Photoillumination of the compound in the presence of supercoiled pBR322 DNA results in cutting of the plasmid to produce nicked circular and linear DNA. Quantitative analysis of agarose gel data shows that bpV(phen) is a single strand nicking agent exhibiting sequence and/or base specificity.

DNA, Circular↗
PubMedDate not supplied

Molecular recognition between oligopeptides and nucleic acids: DNA binding specificity of a series of bis netropsin analogues deduced from footprinting analysis.

A series of tether-linked bis netropsins have been synthesized in order to assess the phasing problem, which arises because of the lack of dimensional correspondence between oligopeptides and oligonucleotides in DNA binding characteristics. The consequences of incorporating variable-length flexible and rigid tethers [poly(methylene), Z and E ethylene, m- and p-phenylene] between the two netropsin-like moieties on the DNA binding properties were assessed by DNase I footprinting. The conformational freedom associated with two netropsins linked by a flexible methylene tether allows ligand binding in both a mono- and bidentate fashion, with bidentate binding requiring a minimum linker length of (CH2)3. For compounds possessing rigid tethers, for example, cis and trans ethylene moieties, the cis geometry excludes bidentate ligation while the trans structure favors it. Bis netropsins possessing aryl linking groups have reduced DNA binding affinities. This is most plausibly due to the aryl groups, which are not coplanar with the netropsin moieties, thus blocking the ligand from penetrating deeply into the minor groove of DNA.

Base Sequence↗