Generating an Efficient Arginase Variant for Medical and Industrial Uses: in Silico Engineering

Human arginase is a multifaceted enzyme that can be utilised for various medical and industrial applications, including as a replacement therapy for enzyme-deficient patients and for the industrial production of ornithine. However, no report has explored the in-silico engineering of this novel enzyme. The crystal structure of human arginase 1 was downloaded from the protein databank, and its quality was checked prior to further analysis. CUPSAT and DeepDDG webservers were then employed to nominate the most stable variants, which were prepared by the UCSF Chimera v1.16 modelling system and refined by the GalaxyRefine tool. Docking (i.e., to reference substrate and inhibitor), stability confirmation and dynamics simulations were conducted for all proposed variants, compared to the wild-type version of the enzyme. G119L was the best mutant in all the mentioned aspects, which was afterwards cloned in silico as a final step for the experimental testing thereof. Accordingly, G119L is found to be a valuable arginase mutant that deserves experimental validation to be employed for medical and industrial purposes.