7E56

The mutant crystal structure of endo-polygalacturonase (T316C/G344C) from Talaromyces leycettanus JCM 12802

Summary for 7E56

• Entry DOI: 10.2210/pdb7e56/pdb
• Descriptor: Endo-polygalacturonase (2 entities in total)
• Functional Keywords: endo-polygalacturonase, hydrolase
• Biological source: [Talaromyces] leycettanus
• Total number of polymer chains: 1
• Total formula weight: 34431.41

Authors

Tu, T.,Luo, H.,Yao, B. (deposition date: 2021-02-17, release date: 2021-08-25, Last modification date: 2024-11-13)

Primary citation

Wang, S.,Meng, K.,Su, X.,Hakulinen, N.,Wang, Y.,Zhang, J.,Luo, H.,Yao, B.,Huang, H.,Tu, T.
Cysteine Engineering of an Endo-polygalacturonase from Talaromyces leycettanus JCM 12802 to Improve Its Thermostability.
J.Agric.Food Chem., 69:6351-6359, 2021

PubMed Abstract: Thermostable enzymes have many advantages for industrial applications. Therefore, in this study, computer-aided design technology was used to improve the thermostability of a highly active endo-polygalacturonase from JCM12802 at an optimal temperature of 70 °C. The melting temperature and specific activity of the obtained mutant T316C/G344C were increased by 10 °C and 36.5%, respectively, compared with the wild-type enzyme. The crystal structure of the T316C/G344C mutant showed no formation of a disulfide bond between the introduced cysteines, indicating a different mechanism than the conventional mechanism underlying improved enzyme thermostability. The cysteine substitutions directly formed a new alkyl hydrophobic interaction and caused conformational changes in the side chains of the adjacent residues Asn315 and Thr343, which in turn caused a local reconstruction of hydrogen bonds. This method greatly improved the thermostability of the enzyme without affecting its activity; thus, our findings are of great significance for both theoretical research and practical applications.

PubMed: 34043362
DOI: 10.1021/acs.jafc.1c01618

Experimental method

X-RAY DIFFRACTION (1.4 Å)