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Characterization of diadzein-hemoglobin binding using optical spectroscopy and molecular dynamics simulations.

ABSTRACT: The present study establishes the effectiveness of natural drug delivery mechanisms and investigates the interactions between drug and its natural carrier. The binding between the isoflavone diadzein (DZN) and the natural carrier hemoglobin (HbA) was studied using optical spectroscopy and molecular dynamics simulations. The inherent fluorescence emission characteristics of DZN along with that of tryptophan (Trp) residues of the protein HbA were exploited to elucidate the binding location and other relevant parameters of the drug inside its delivery vehicle HbA. Stern-Volmer studies at different temperatures indicate that static along with collisional quenching mechanisms are responsible for the quenching of protein fluorescence by the drug. Molecular dynamics and docking studies supported the hydrophobic interactions between ligand and protein, as was observed from spectroscopy. DZN binds between the subunits of HbA, ?15 Å away from the closest heme group of chain ?1, emphasizing the fact that the drug does not interfere with oxygen binding site of HbA.

SUBMITTER: Sengupta B

PROVIDER: S-EPMC3409843 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Characterization of diadzein-hemoglobin binding using optical spectroscopy and molecular dynamics simulations.

Sengupta Bidisha B Chakraborty Sandipan S Crawford Maurice M Taylor Jasmine M JM Blackmon Laura E LE Biswas Pradip K PK Kramer Wolfgang H WH

International journal of biological macromolecules 20120516 3

The present study establishes the effectiveness of natural drug delivery mechanisms and investigates the interactions between drug and its natural carrier. The binding between the isoflavone diadzein (DZN) and the natural carrier hemoglobin (HbA) was studied using optical spectroscopy and molecular dynamics simulations. The inherent fluorescence emission characteristics of DZN along with that of tryptophan (Trp) residues of the protein HbA were exploited to elucidate the binding location and oth ...[more]

PMID: 22609682

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Characterization of diadzein-hemoglobin binding using optical spectroscopy and molecular dynamics simulations.

Publications

Characterization of diadzein-hemoglobin binding using optical spectroscopy and molecular dynamics simulations.

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