Experimental studies of OH° radical/pressure dependence of arginase activity using a molecular chromatography approach

Abstract

Arginase is an enzyme which plays a role in pathophysiology such as hypertension. Here we demonstrated for the first time the direct implication of pressure and OH° radical formation on the arginase activity via a novel analytical procedure. Pressure increased arginase activity in the range 12-52bars. Activation by OH° radical showed a hyperbolic response. The OH° radicals produced were significantly inhibited by sulfasalazine (SAZ) and the inhibition of OH° radicals parallels the inhibition of arginase activity.

Analysis of the activation of acetylcholinesterase by carbon nanoparticles using a monolithic immobilized enzyme microreactor: role of the water molecules in the active site gorge

“…The catalysis rate and the V max values were higher at the presence of CNPs in the medium ( Figure 3 and Table 1), while a little decrease was observed on the K m . These data indicated classical activation kinetic with an increase in the substrate affinity to the active site [14][15][16] and suggested that CNPs affect positively proximity and enzyme orientation for its interaction with the substrate. This can be achieved by a structural orientation of histidine residue in the active site gorge, by increasing affinity of substrate to the peripheral site or by increasing the rate of substrate entering to the active site following a structural conformational change.…”