I'm trying to figure this out. I was given two graphs of an engineered protein and I'm suppose to explain what happened.
First graph.
X-axis pH
Y-Axis Log [H+/min]
Graph is a straight line with a positive slope.
Second graph.
X-axis pH
Y-Axis total H+
Graph looks like a titration of an amino acid. Starts low, Increases to a plateu that levels out then increase to another plateu.
The rate was monitored for the initial 5 minutes using acetic anhydride for the first graph and the total number of protons formed in 30 minutes is recorded for the second graph. No numerical values are given.
I figured since acetic anhydride is pulling protons off of my protein they are coming off at a constant rate, raising the pH. I thought there could be lysine or serine groups exposed to the acetic anhydride and these could be what donates the protons. I also thought the acetic anhydride caused a conformational change in the protein and possible exposed the hydrophobic region.
Is my thinking correct or is there something I'm missing?