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Author Spotlight: Characterizing DNA G-Quadruplex by Bis-3-Chloropiperidine Based Chemical Mapping
Published on: May 12, 2023
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Pyrrolobenzodiazepines (PBDs) do not bind to DNA G-quadruplexes
Khondaker M Rahman1, David B Corcoran1, Tam T T Bui1
1Department of Pharmacy, Institute of Pharmaceutical Science, King's College London, London, United Kingdom.
Plos One
|August 19, 2014
Summary
Pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) interact with DNA quadruplexes via their C8-substituents, not the PBD core. This finding clarifies PBD mechanisms for antibody-drug conjugates and other clinical applications.
Area of Science:
- Medicinal Chemistry
- Molecular Biology
- Biochemistry
Background:
- Pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) are DNA-interactive agents known to bind the minor groove of duplex DNA.
- Previous studies suggested PBDs bind to DNA quadruplexes, a surprising observation given their structural specificities.
Purpose of the Study:
- To investigate the interaction of various PBD molecules with different DNA quadruplex structures.
- To elucidate the binding mechanism of PBDs to DNA quadruplexes.
Main Methods:
- DNA Thermal Denaturation
- Circular Dichroism spectroscopy
- Molecular Dynamics Simulations
Main Results:
- PBDs lacking large C8-substituents showed negligible affinity for DNA quadruplexes.
- PBDs with large, π-system-containing C8-substituents exhibited some interaction with quadruplexes.
- Molecular dynamics simulations indicated that PBDs interact with quadruplex DNA via their C8-substituents.
Conclusions:
- The PBD core is not the primary interacting moiety with DNA quadruplexes.
- The C8-substituent dictates PBD interaction with DNA quadruplexes, clarifying previous findings.
- Understanding this mechanism is crucial for developing PBD-based therapeutics, including antibody-drug conjugates.
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