A mixture of two proteins with the same pI and molecular weights (MW) of 10,000 and 15,000 daltons, respectively, are applied to a gel filtration column. What happens during elution?
In a biochemistry laboratory a student added ammonium sulfate to a tube containing a buffered protein solution. The student then centrifuged the solution. What was the student probably trying to do?
An enzyme works well at as a catalyst at a pH of 7.2. It is found that catalytic activity is significantly less at a pH of 8.4. Which could likely cause the decrease in activity?
The isoelectric point of alanine is pH = 6.15. It is mixed with proline (pHCOOH = 2.0; pHNH2 = 10.6), and the mixture is placed in an electric field at pH 6.15. Which statement is true?
The pH inside cells is normally near pH 7. At pH 7 which statement is true about the charges (ionization state) of the α-Carboxyl and α-Amino groups of an amino acid?
Which amino acid is ideal for the transfer of protons within the catalytic site of enzymes due to the presence of significant amounts of both the protonated and deprotonated forms of its side chain at biological pH?
Selenocysteine, N-formylmethionine and pyrrolysine are found in many proteins. These amino acids are considered standard amino acids along with 20 common amino acids because they