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Amine group should instead be a hydroxyl group?

I noticed that there seems to be an extra amine group, as there are only nine amino acids, but there are ten nitrogen atoms in the main chain (which means not including the nitrogen atoms in the R-group for asparagine and glutamine). I think that the amine group in the bottom left corner (the one on the left side of the glycine) should instead be a hydroxyl group, which would make it, when combined with the double-bonded oxygen atom attached to the same carbon atom, a carboxyl group. By the way, why is there no methionine? I thought that every amino acid had to begin with methionine at the amine end. So shouldn't the upper cysteine be a methionine? — Preceding unsigned comment was added by 50.235.102.246 (talk) 16:35, 19 March 2018 (UTC)

Neither of those issues is an error. The C-terminal end is correctly drawn as glycinamide, a modification of glycine. Also, there is no reason that every peptide must have a methionine at the N-terminus. In oxytocin, the N-terminal amino acid is cysteine. Ed (Edgar181) 22:44, 19 March 2018 (UTC)