In this dehydrating syntheses a single H separates from the amine group in one amino acid, while the other is in the hydroxyl [OH] from the carboxyl group in the joining amino acid.
or
The assembly of AAs into proteins takes place in our cells by a linkage which involves the loss of 2 Hydrogen atoms from the amino [NH3] site and the loss of an atom of oxygen form the carboxyl [CO2] site of the adjacent amino acid, forming a molecule of H2O.
You're the one, chemscience, that's said both. Which scenario are you claiming now?
And do bacteria and whales dissolve in seawater? They're made largely of polypeptides. How does that work?
"The wretched world lies now under the tyranny of foolishness; things are believed by Christians of such absurdity as no one ever could aforetime induce the heathen to believe." - Agobard of Lyons,
ca. 830 AD