Inhibition of <i>Pf</i>SpdS activity.

Abstract

<p>(A) Lineweaver-Burke plot for 4MAN. Reciprocal velocity <i>vs</i>. reciprocal putrescine concentration at 0.1 mM dcAdoMet in presence of 4MAN at final concentrations of 0 μM, open circles (○); 20 μM, filled triangles (▲); 40 μM, open diamonds (◊); or 100 μM, filled circles (●). Solid lines are linear regression fits for each 4MAN concentration. Each symbol represents the average of two technical replicates from one independent measurement (range = < 17%). (B) Secondary plot for 4MAN. The slope of each line in panel A is plotted <i>vs</i>. 4MAN concentration. The solid line is the linear regression fit, yielding the K_i value of 8.2 μM from the abscissa intercept. (C) Lineweaver-Burke plot for AdoDATO. Reciprocal velocity <i>vs</i>. reciprocal putrescine concentration at 0.1 mM dcAdoMet in presence of AdoDATO at final concentrations of 0 μM, open circles (○); 5 μM, filled triangles (▲); 10 μM, open diamonds (◊); or 25 μM, filled circles (●). Solid lines are linear regression fits for each AdoDATO concentration. Each symbol represents the average of two technical replicates from one independent measurement (range = < 9%). Two independent measurements were performed with reproducible results. (D) Secondary plot for AdoDATO. The slope of each line in panel C is plotted <i>vs</i>. AdoDATO concentration. The solid line is the linear regression fit, yielding the K_i competitive value of 3.4 μM from the abscissa intercept.</p