>3u4n_A mol:protein length:21 Insulin A chain GIVEQCCTSICSLYQLENYCN >3u4n_B mol:protein length:29 Insulin B chain FVNQHLCGSHLVEALYLVCGERGFCYTPK >3u4n_B mol:protein length:29 Insulin B chain FVNQHLCGSHLVEALYLVCGERGFCYTPK