Noncovalent Carbon-Bonding Interactions in Proteins.

Area of Science:

• Biochemistry
• Structural Biology
• Computational Chemistry

Background:

• Conventional noncovalent interactions like hydrogen bonds and halogen bonds are crucial in biological systems.
• Carbon bonds (C-bonds), a type of noncovalent interaction, have not been widely recognized in biological contexts.

Purpose of the Study:

• To investigate the existence and significance of carbon bonds (C-bonds) in protein structures.
• To quantify the energetic contribution of C-bonds and elucidate their role in biological processes.

Main Methods:

• Detailed analysis of protein structures.
• Quantum chemical calculations to determine C-bond energies and characteristics.

Main Results:

• Demonstrated the ubiquitous presence of C-bonds in proteins.
• Precisely determined the energies associated with C-bonds.
• Showed that C-bonds contribute enthalpically to hydrophobic interactions.
• Identified the significant role of C-bonds in the photodissociation of myoglobin and nucleobase-protein binding.

Conclusions:

• Carbon bonds are an important, yet underappreciated, noncovalent interaction in proteins.
• C-bonds influence protein structure, stability, and function, particularly in hydrophobic interactions and specific molecular recognition events.