English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Histidine substitution in the most flexible fragments of firefly luciferase modifies its thermal stability.

MPS-Authors
/persons/resource/persons36515

Rezaei-Ghaleh,  N.
Research Group of Protein Strcture Determination using NMR, MPI for biophysical chemistry, Max Planck Society;

Locator
There are no locators available
Fulltext (public)

2478818.pdf
(Publisher version), 3MB

Supplementary Material (public)
There is no public supplementary material available
Citation

Rahban, M., Salehi, N., Saboury, A. A., Hosseinkhani, S., Karimi-Jafari, M. H., Firouzi, R., et al. (2017). Histidine substitution in the most flexible fragments of firefly luciferase modifies its thermal stability. Archives of Biochemistry and Biophysics, 629, 8-18. doi:10.1016/j.abb.2017.07.003.


Cite as: http://hdl.handle.net/11858/00-001M-0000-002D-E3CF-9
Abstract
Molecular dynamics (MD) at two temperatures of 300 and 340 K identified two histidine residues, His461 and His489, in the most flexible regions of firefly luciferase, a light emitting enzyme. We therefore designed four protein mutants H461D, H489K, H489D and H489M to investigate their enzyme kinetic and thermodynamic stability changes. Substitution of His461 by aspartate (H461D) decreased ATP binding affinity, reduced the melting temperature of protein by around 25 degrees C and shifted its optimum temperature of activity to 10 degrees C. In line with the common feature of psychrophilic enzymes, the MD data showed that the overall flexibility of H461D was relatively high at low temperature, probably due to a decrease in the number of salt bridges around the mutation site. On the other hand, substitution of His489 by aspartate (H489D) introduced a new salt bridge between the C-terminal and N-terminal domains and increased protein rigidity but only slightly improved its thermal stability. Similar changes were observed for H489K and, to a lesser degree, H489M mutations. Based on our results we conclude that the MD simulation-based rational substitution of histidines by salt-bridge forming residues can modulate conformational dynamics in luciferase and shift its optimal temperature activity.