Characterization of the reconstituted wt-bOp and T90A-bOp with AT retinal and the analogue 13E-RET.

aMaximum absorbance in the visible spectrum of the bound retinal.
bHalf-life for the reconstitution of the bOps with all-trans and 13E-RET.
cChange in the absorbance maximum of the pigment band after incubation of the chromoproteins in the dark. DA, dark-adapted; LA, light-adapted.
dHalf-life of hydrolysis of suspensions 10 µM of chromoprotein with 40 mM NH2OH in 5 mM phosphate buffer.
eTm of thermal denaturation of the proteins measured as the retinal release with temperature.
fpKa of Asp85 in water.
gpKa of Asp85 in 150 mM KCl.
hIndirect measurement of the proton transport function in the chromoproteins measured as the light-induced transient absorbance change of a 15 µM protein suspension in the presence of 50 µM pyranine dye.