Molecular Crowder-Induced Structural Transformation of the DNA Dodecamer

Area of Science:

• Biochemistry and Biophysics
• Molecular Biology
• Computational Biology

Background:

• Molecular crowding is a key factor influencing biomolecular structure, stability, and function within cellular environments.
• In vivo, crowding involves biomolecules like proteins and nucleic acids; in vitro, it uses various organic and inorganic molecules.
• Understanding crowding effects on DNA conformation is vital for comprehending genetic processes.

Purpose of the Study:

• To investigate the impact of molecular crowding on the structural transformations of a DNA dodecamer.
• To compare the effects of aspartame and polyethylene glycol (PEG-200) as distinct crowding agents on DNA structure.
• To elucidate how different crowders modulate DNA organization in crowded systems.

Main Methods:

• Atomistic molecular dynamics simulations were employed to study DNA dodecamer structural changes.
• The interactions of aspartame and PEG-200 with DNA were analyzed.
• Key structural descriptors were calculated to assess DNA organization under crowding conditions.

Main Results:

• Distinct interaction patterns were observed: PEG-200 accumulated at DNA termini, while aspartame favored DNA grooves.
• Aspartame demonstrated concentration-dependent effects, stabilizing DNA at lower concentrations and causing perturbations at higher concentrations.
• Molecular crowding was shown to influence overall DNA organization through specific crowder-DNA interactions.

Conclusions:

• Different molecular crowders exert unique influences on DNA structure and organization.
• Aspartame and PEG-200 interact differently with DNA, leading to varied structural outcomes.
• These findings enhance our understanding of DNA behavior in crowded environments with implications for biological and biomimetic systems.