Amino acid residue question?

Question

I am given a recombiant protein, but its activity level is low, so it is not exactly functioning. I have read up something about changing the amino acid residue for certain amino acid residue to help solve the problem. However, I do not know how to change and have no idea how a change in residue would help in increasing the activity level of the protein.

Here are some examples of the amino acid residue that is given to me to alter. amino acid residues chosen for alteration
Ser106 to Asp106
Thr69 to Ala69
Phe44 to Ala44
Asp35 to Ala35
Arg18 to Glu18

Can anyone provide me with any insights on how to alter and also how it helps me to affect the nature of the protein.

Answer 1

Without knowing what the protein is supposed to do, it is impossible to tell what may happen with the mutations. First of all, the changes in amino acid residues can be achieved most commonly by generating mutation(s) at the DNA level. In other words, you need to take the cDNA, the gene cloned in a plasmid most likely, and redesign the coding sequence so that instead of coding for Ser106, it will code for an Asp. Many bio-tech companies have kits that help in this step.

Whether a certain change will or will not affect function depends on what is known of the amino acid residues in question. For example, if Ser106 is the residue for phosphorlyation and the resulted phosphoprotein is functional, then Ser106 to Asp106 will not be good to improve the function of your recombinant protein.

The question is too hypothetical and there is no good answer to this.

Answer 2

nicely i replaced into taught that when in a protein, amino acids could now be termed amino acid residue... possibly as a results of its contribution to the upkeep of the protein structure... So in short , amino acid is an same as amino acid residue ...