Question

Based on the chemical properties of the residues, determine which sequences would exhibit which structural properties.

(a) Most likely an amphipathic α helix


(b) Most likely an amphipathic β sheet


(c) Most likely a turn/loop


(d) Not amphipathic



(1) Asn-Leu-Ala-Asp-Ser-Phe-Arg-Gin-lle


(2) Gin-lle-Thr-Phe-Thr-Leu-Gin-Val Ser


(3) Lys-Gin-Asn-Glu-Pro-Arg-Ala-Asn-Glu


(4) Lys-Ser-Thr-Asn-Glu-Gin-Asn-Ser-Arg


(5) Ala-Phe-Leu-Val-lle-Trp-Phe-Val-Ala


(6) Arg-Phe-GIn-lle-His-Val-GIn-Phe-Glu

Answer 1

a) Most likely an amphipathic α helix: Asn−Leu−Ala−Asp−Ser−Phe−Arg−Gln−Ile

b) Most likely an amphipathic β sheet: Gln−Ile−Thr−Phe−Thr−leu−Gln−Val−Ser

c) Most likely a turn/loop: Lys−Gln−Asn−Glu−Pro−Arg−Ala−Asn−Glu

d) Not amphipathic: Lys−Ser−Thr−Asn−Glu−Gln−Asn−Ser−Arg

Step-by-step explanation:

Amino acids, methionine, alanine, leucine, glutamate, and lysine are made of an alpha helix. The amino acids tryptophan, tyrosine, phenylalanine, and beta such as leucine, threonine, and valine form a beta structure. The remaining amino acids would tend to form a non-amphipathic chain.