Regulating the Heme Active Site by Covalent Modifications: Two Case Studies of Myoglobin

• Published in: Chembiochem : a European journal of chemical biology Vol. 25; no. 3; pp. e202300678 - n/a
• Main Authors: Chen, Ze‐Yuan, Yuan, Hong, Wang, Huamin, Sun, Li‐Juan, Yu, Lu, Gao, Shu‐Qin, Tan, Xiangshi, Lin, Ying‐Wu
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.02.2024
• Subjects: Catalytic Domain; covalent modification; Crystallography; Heme - chemistry; heme active site; Heme proteins; Hydrogen peroxide; Kinetics; Myoglobin - chemistry; Myoglobin - genetics; Myoglobin - metabolism; Myoglobins; Peroxidase; Phenols; Protein Conformation; protein engineering; Proteins; Sulfhydryl Compounds; Triazoles; X-ray structure; protein engineering; heme active site; covalent modification; heme proteins; X-ray structure
• ISSN: 1439-4227; 1439-7633
• DOI: 10.1002/cbic.202300678

Using myoglobin (Mb) as a model protein, we herein developed a facial approach to modifying the heme active site. A cavity was first generated in the heme distal site by F46 C mutation, and the thiol group of Cys46 was then used for covalently linked to exogenous ligands, 1H‐1,2,4‐triazole‐3‐thiol and 1‐(4‐hydroxyphenyl)‐1H‐pyrrole‐2,5‐dione. The engineered proteins, termed F46C‐triazole Mb and F46C‐phenol Mb, respectively, were characterized by X‐ray crystallography, spectroscopic and stopped‐flow kinetic studies. The results showed that both the heme coordination state and the protein function such as H2O2 activation and peroxidase activity could be efficiently regulated, which suggests that this approach might be generally applied to the design of functional heme proteins. Covalent modification: A facial approach was developed to regulate the heme active site of heme protein by cavity generation, followed by covalent modifications, as shown by the two case studies using myoglobin as a model protein.