7B4Q

Structure of a cold active HSL family esterase reveals mechanisms of low temperature adaptation and substrate specificity

Summary for 7B4Q

• Entry DOI: 10.2210/pdb7b4q/pdb
• Descriptor: Lipase, 1,2-ETHANEDIOL, GLYCEROL, ... (6 entities in total)
• Functional Keywords: bacillus cohnii, esterase, low temperature adapted, regio-selective esterase, hormone-sensitive family, hydrolase, lipase
• Biological source: Bacillus cohnii NBRC 15565
• Total number of polymer chains: 2
• Total formula weight: 71535.45

Authors

Rizkallah, P.J.,Jones, D.D.,Noby, N.,Auhim, H. (deposition date: 2020-12-02, release date: 2021-12-15, Last modification date: 2024-01-31)

Primary citation

Noby, N.,Auhim, H.S.,Winter, S.,Worthy, H.L.,Embaby, A.M.,Saeed, H.,Hussein, A.,Pudney, C.R.,Rizkallah, P.J.,Wells, S.A.,Jones, D.D.
Structure and in silico simulations of a cold-active esterase reveals its prime cold-adaptation mechanism.
Open Biology, 11:210182-210182, 2021

PubMed Abstract: Here we determined the structure of a cold active family IV esterase (EstN7) cloned strain N1. EstN7 is a dimer with a classical α/β hydrolase fold. It has an acidic surface that is thought to play a role in cold-adaption by retaining solvation under changed water solvent entropy at lower temperatures. The conformation of the functionally important cap region is significantly different to EstN7's closest relatives, forming a bridge-like structure with reduced helical content providing greater access to the active site through more than one substrate access tunnel. However, dynamics do not appear to play a major role in cold adaption. Molecular dynamics at different temperatures, rigidity analysis, normal mode analysis and geometric simulations of motion confirm the flexibility of the cap region but suggest that the rest of the protein is largely rigid. Rigidity analysis indicates the distribution of hydrophobic tethers is appropriate to colder conditions, where the hydrophobic effect is weaker than in mesophilic conditions due to reduced water entropy. Thus, it is likely that increased substrate accessibility and tolerance to changes in water entropy are important for of EstN7's cold adaptation rather than changes in dynamics.

PubMed: 34847772
DOI: 10.1098/rsob.210182

Experimental method

X-RAY DIFFRACTION (1.61 Å)