Which one of the following amino acids is most likely to be found in the trans membrane region of a protein?
Ans:C.)Leucine. Cell membrane is a complex structure composed of lipid, proteins and carbohydrate. Membrane lipids form bilayer. The unique characteristic of this layer is that it has its hydrophobic ends in the centre of membrane while its hydrophilic ends lie on the outer surface of membrane. Hydrophobhic or Non polar aminoacid are present in transmembrane region. Hydrophillic or polar amino acids are present on outer surface of membrane. Leucine is a hydrophobic a.a so it lies in transmembrane region Polar Amino Acids (Hydrophilic)Charged Acidic Amino acids-Aspaic Acid (Aspaate), Glutamic Acid (Glutamate) Basic Amino Acids-Histidine, Arginine,Lysine Uncharged Aliphatic amino acid with hydroxyl group as side chain: Serine, Threonine Aliphatic amino acids with amide group: Asparagine, Glutamine Simple Amino acid: Glycine alone Sulfur containing Aminoacid: Cysteine alone. Nonpolar Amino Acids (Hydrophobic) Simple amino acid: Alanine alone Sulfur containing amino acid: Methionine alone Aromatic Amino acids except Histidine . All branched chain amino acids: Leucine,Isoleucine and Valine Imino acid: Proline
Lysine
Arginine
Leucine
All