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Albany 2019: 20th Conversation - Abstracts

Albany 2019
Conversation 20
June 11-15 2019
Adenine Press (2019)

The effect of porphyrins configuration on the hydrodynamic behavior of DNA solutions

The present work summarizes possibilities of a viscometry method for studying the conformational changes of DNA at interaction with porphyrins. For elucidating the influence of porphyrin structure by varying the metal center, peripheral substituents and their positions in pyridylic ring on binding mode and intensity of interaction with DNA water soluble cationic meso-tetra-(3N- and 4N-hydroxy¬ethylpyridyl) (Barkhudaryan & Ananyan, 2014, 2016), (3N- and 4N-allylpyridyl) (Barkhudaryan & Ananyan, 2017, 2018) porphyrins and their metal complexes with Cu and Co were studied via viscometry and UV-vis absorption spectroscopy. It was shown, that planar porphyrins interact with DNA by intercalation mode (Fig. a, b), excepting CuTAllPyP4 which interacts with DNA by partial intercalation mod (Barkhudaryan & Ananyan, 2018). Moreover, the planar porphyrins with allylpyridyl peripheral substituents interact with DNA considerably more intensively than with hydroxyethylpyridyl substituents. Comparison of different locations of peripheral substituents on pyridylic rings leads to the conclusion that the H2THOEtPyP3 and H2TALPyP3 and their metallocomplexes bind to DNA more preferably than H2THOEtPyP4, H2TALPyP4 and their metallocomplexes. This fact can be explained by the preferred arrangement of 3N-porphyrins on the DNA helix compared to 4N-porphyrins. The change of chemical structure of peripheral radicals and their positions on pyridylic ring of porphyrins does not absolutely affect on the mechanism of interaction of outside binders such as Co-porphyrins (Fig. c). The viscometry and spectrophotometric measurements are in good agreement (Barkhudaryan & Ananyan, 2014, 2016, 2017, 2018).

ananyan-2-fig.gif

References

    V.G. Barkhudaryan, G.V. Ananyan, Y. B. Dalyan, S.G. Haroutiun (2014). Development of viscometric methods for studying the interaction of various porphyrins with DNA. Part I. J. Porph.& Phthalocyanines 18(07), 594–599.

    V.G.Barkhudaryan, G.V.Ananyan (2016). Development of viscometric methods for studying the interaction of various porphyrins with DNA.Part II. J. Porph.& Phthalocyanines 20(07), 766–772.

    V.G. Barkhudaryan, G.V.Ananyan (2017). Development of viscometric methods for studying the interaction of various porphyrins with DNA. Part III. J. Porph.& Phthalocyanines. 21(02), 110–115.

    V.G. Barkhudaryan, G.V.Ananyan (2018). Development of viscometric methods for studing the interaction of various porphyrins with DNA. Part IV. J. Porph. & Phthalocyanines. 22(11), 1022-1029.

Vigen G. Barkhudaryan*
Gayane V. Ananyan

Department of Molecular Physics
Yerevan State University
1 Alex Manoogian St. 0025,
Yerevan, Armenia

(vigen@ysu.am)