The "intruder" hypothesis and selection against arginine.
D001120:Arginine / Q000378:metabolism*; D005075:Biological Evolution; D005815:Genetic Code; D005998:Glycine / Q000378:metabolism; D007136:Immunoglobulins / Q000096:biosynthesis; D008239:Lysine / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation; D014176:Protein Biosynthesis; D012333:RNA, Messenger; D012694:Serine / Q000378:metabolism
D007136:Immunoglobulins; D012333:RNA, Messenger; D012694:Serine; D001120:Arginine; D008239:Lysine; D005998:Glycine