Question

A bacterial culture grown for 48 hr in a medium containing radioactive sulphur would incorporate the radiolabel in the tetra-peptide

• A. Serine-cysteine-tyrosine-methionine
• B. Threonine-lysine-aspartic acid-glutamic acid
• C. Alanine-proline-histidine-glycine
• D. Tryptophan-phenylalanine-valine-isoleucine

Answer 1

The correct option is A Serine-cysteine-tyrosine-methionine

Only few amino acids contain sulphur in their structure. They are cysteine and methionine. When the bacterial cells are allowed to grow in the medium for 48 hours, the radioactive sulphur will be incorporated in the tetra-peptide sequence containing cysteine and methionine.

Thus, the correct answer is option A.