User:Paul Rothenberg/Notebook/Pauls Notebook/2013/05/24

Project name

Main project page Previous entry      Next entry

Reaction of OPD and H2O2 n MeOH with Mb/Tris Catalyst Objectives: 1. Continue analysis of OPD+H2O2 reaction with Mb in Tris catalyst catalyst at the same temperatures Procedure: 1. Followed same procedure as 5/20 with Mb lyopholized in Tris/Citrate and KCl from 5/22 Observations: The Mb in Tris had no anomaly peaks at any temperature, he Mb in Tris had the highest absorbances at 5C and 45C, and the Mb in Citrate did not produce results similar to the previous trials. There was no peak at either 420 nm or 460 nm, and the 45C trial had completely skewed data from the previous temperatures. Reanalysis of Reaction of OPD and H2O2 with Mb/Citrate Catalyst in MeOH From this data, it seemed there may be some reaction between citrate and myoglobin directly. Some research was done into this, and there could be some correlation leading to the inconsistent data. This article was interesting in the relationship between myoglobin and citrate. Here is an article about low pH Myoglobin photoproducts. Just found another article about metastable intermediates in myoglobin at low pH. Link is here. The authors discuss that at a low pH, the proximal histidine is protonated, allowing for the uptake of, as they mention, CO, or any other compound. CO may not necessarily be what's binding in this case. If we can determine what products are formed in the reaction, we can infer more about the reactivity of the overall protein and the iron center. (added on 5/30). References: 1. Lin et al, Myoglobin content and citrate synthase activity in different parts of the normal human heart, Journal of Applied Physiology, 1990, 69(3), 899-901. Found here.