Extremophiles are the organisms that survive in environments which are inhospitable to other creatures. This thesis made an attempt to understand the enviromental effects, in particular saline, on enzyme structure by using three dimensional NMR. The enzyme DHFR1 from halophile Haloferaxi volcanii is complexed with its coactor NADPH, and the saline effects on the complex are studied by comparison with its apoenzyme, hvDHFR1. Backbone chemical shift assignments of the hvDHFR1:NADPH complex were attained which can be functional (along with future work) in understanding the effect of salts on enzyme structure, function, and flexibility. A total of 27 amino acids were found to show a significant change upon binding of NADPH and their positions were identified on enzyme complex. The secondary structure of hvDHFR1:NADPH is also predicted and overall global structure is found to be similar with the crystal structure of hvDHFR1 with few changes.