A ball-and-stick model structure of polar amino acid glutamine (Gln, Q). Carbon in blue-grey, oxygen in red, nitrogen in green, hydrogen in silver. Drawn in Inkscape.
A ball-and-stick model structure of non-polar, hydrophobic amino acid methionine (Met, M). Carbon in blue-grey, oxygen in red, nitrogen in green, hydrogen in silver, sulfur in yellow. Drawn in Inkscape.
A ball-and-stick model structure of acidic (negatively-charged) amino acid glutamic acid (Glu, E). Carbon in blue-grey, oxygen in red, nitrogen in green, hydrogen in silver. Drawn in Inkscape.