Question

In $\beta$-pleated secondary protein structure there are

• A. Two or more polypeptide chains
• B. Hydrogen bonds between adjacent polypeptide chains
• C. Parallel or antiparallel polypeptides
• D. All the above

Answer 1

Answer: (D)

All the above

Protein is formed by the amino acids which are linked together by peptide bonds.

β-pleated secondary protein structure is formed by the parallel or anti-parallel polypeptide chain linked together by H - bonds. It is stabilized by the hydrogen bonds formed between NH and Co of the adjacent polypeptide chain. The distance between the adjacent amino acids are 3.5 A${}^o$.

So, the correct answer is option D.