Edward A Berry

9 Questions 21 Answers 0 Followers

Questions related from Edward A Berry

Predict solubility of organic compounds?

Is there a formula, or a program or web server, that will predict the solubility of an arbitrary organic compound in various solvents?

30 August 2018 6,480 3 View

What is a good method to determine the relative stoichimetry of subunits in a heteromultimeric protein?

For example, a dimer of ten different subunits, to see if one subunit is present at only one copy per dimer. Can Edman degradation of the whole complex solve this, by the ratio of different amino...

09 August 2018 1,515 4 View

Which isomer of tetramethylbenzidine (TMBZ) works best as a peroxidase substrate for detecting covalent heme in SDS gels?

Thomas et al. (Anal Biochem 75, 177) recommended using the 3,3',5,5'-tetramethyl isomer, but googling for online recipes shows a number of labs are using N,N,N',N'-tetramethyl. Do they both...

08 February 2017 6,874 2 View

Can His-tagged proteins be eluted from Ni-NTA by low pH instead of imidazole?

And if so, how low does the pH need to be to elute cleanly in a small volume?

02 September 2015 8,315 3 View

What is the source of varying levels of 2,3-BPG that regulate O2 affinity of HGb?

The affinity of hemoglobin for oxygen is regulated by varying concentration of BPG (2,3-bisphosphoglycerate), which binds to and stabilizes the deoxy form. BPG is a side product of glycoloysis....

24 August 2015 4,767 7 View

Are there bifurcated H-bonds in the transition of a protein helix from alpha to 3-10?

Sometimes alpha helices have segments of 3/10 helix at the end. In the transition area, there are residues for which the amide N is equally close to the carbonyl oxygens of the residues 3 and 4...

08 April 2015 6,339 2 View

Should BHT be added to ether containing high level of peroxide?

Hypothetical question here- If a bottle of diethyl ether or dioxane is found to have a dangerous level of peroxide, should a radical scavenger/antioxidant like BHT be added to reduce the risk of...

08 April 2015 3,931 3 View

Is there an easy way to measure the concentration of PMSF in a solution, say by rapid quantitative reaction to form a colored derivative?

PMSF (phenyl-methyl-sulfonyl-fluoride) is used as a serine protease inhibitor because it derivatizes the catalytic serine in the active site. However it also reacts with water or (I believe at a...

14 March 2014 5,341 4 View

Why are the distal and proximal histidines in myoglobin or hemoglobin, so named?

Is it because one is on the near side, and the other on the far side, of the heme in some standard viewing orientation? Because one is closer to the heme iron than the other? One is more...

22 December 2012 4,820 5 View