Question

Which of the following techniques may not be used to produce thermophilic enzymes?

(a) Internal salt link

(b) Extra internal hydrophobic residues

(c) Suitable exterior substitutions

(d) Primary structure of putative enzyme is proposed with an asparagine residue replacing the serine present in the native enzyme

This question was addressed to me in an international level competition.

Asked question is from Future Prospects in section Enzyme Technology Future Prospects of Enzyme Technology

Answer 1

Right answer is (d) Primary structure of putative enzyme is proposed with an asparagine residue replacing the serine present in the native enzyme

The explanation is: Primary structure of putative enzyme is proposed with an asparagine residue replacing the serine present in the native enzyme is a major step involved in site directed mutagenesis. The techniques which may be used to produce thermophilic enzymes are as follows:

• Addition of just a few extra hydrogen bonds, an internal salt link and extra internal hydrophobic residues which will give a slightly more hydrophobic core.

• Suitable exterior substitutions to conserve the secondary structure of the enzyme which ensures more predictable outcome.