Natural and artificial proteins containing cadmium

Area of Science:

• Biochemistry
• Structural Biology
• Bioinorganic Chemistry

Background:

• Proteins binding cadmium (Cd(II)) are crucial for biological processes like gene expression and detoxification.
• Understanding the structural and dynamic properties of Cd(II)-binding proteins is essential.

Purpose of the Study:

• To elucidate the structure, spectroscopy, and dynamics of proteins binding Cd(II) using designed protein models.
• To correlate physical properties of Cd(II) binding with protein structure.

Main Methods:

• Utilizing three-stranded coiled coils (3SCCs) based on TRI and GRAND peptides as model systems.
• Employing (113)Cd NMR spectroscopy and perturbed angular correlation ((111m)Cd PAC) experiments.
• Analyzing binding and deprotonation constants to understand Cd(II) interactions.

Main Results:

• Established a correlation between (113)Cd NMR chemical shifts and protein structures derived from (111m)Cd PAC.
• Characterized motional processes involved in Cd(II) transport within protein structures.
• Demonstrated the utility of designed 3SCCs for studying Cd(II) coordination in thiolate-rich environments.

Conclusions:

• Designed coiled-coil proteins provide valuable insights into Cd(II) binding mechanisms.
• The study clarifies the role of Cd(II) chemistry in biological systems, including gene regulation and detoxification pathways.