Oxidative folding of proteins

Area of Science:

• Biochemistry and Molecular Biology
• Protein Folding and Dynamics

Background:

• Oxidative protein folding is essential for generating functional proteins with correct three-dimensional structures.
• Disulfide bonds play a critical role in stabilizing protein tertiary structures, but their formation requires specific oxidative conditions.
• Understanding the mechanisms of oxidative folding is key to comprehending protein biogenesis and misfolding-related diseases.

Purpose of the Study:

• To review and illustrate the process of protein oxidative folding using bovine pancreatic ribonuclease A (RNase A) as a model system.
• To elucidate the interplay between protein conformational folding and disulfide bond formation/regeneration.
• To characterize distinct pathways and intermediate species involved in oxidative folding.

Main Methods:

• Review of existing literature on protein oxidative folding.
• Detailed examination of bovine pancreatic ribonuclease A (RNase A) folding pathways.
• Analysis of disulfide bond formation kinetics and structural intermediates.

Main Results:

• The study emphasizes the 'locking in' of native disulfide bonds by stable tertiary structures in intermediate species.
• Two distinct types of structured, metastable disulfide species were identified based on thiol and disulfide group protection.
• Four generic pathways characterizing the oxidative folding of RNase A were delineated and described.

Conclusions:

• Protein tertiary structure significantly influences and stabilizes the formation of native disulfide bonds during oxidative folding.
• The identification of distinct metastable species and folding pathways provides a deeper mechanistic understanding of oxidative folding.
• This work contributes to the fundamental knowledge of protein biogenesis and has implications for protein engineering and therapeutic protein development.