glycine + valine-->glycine - valine+H2O
What happens with this reaction and where does water molecule come from
In the reaction you've mentioned, glycine and valine are being combined. The product of this reaction is glycine - valine, and a water molecule (H2O) is being formed.
To understand what happens in this reaction, let's start with the chemical structures of glycine and valine. Glycine is the simplest amino acid, consisting of an amino group (-NH2), a carboxyl group (-COOH), and a hydrogen atom (-H). Valine, on the other hand, is a branched-chain amino acid, with an additional side chain (-CH(CH3)2).
When glycine and valine combine, the amino group of glycine reacts with the carboxyl group of valine, resulting in the formation of a peptide bond. The amino group of glycine (-NH2) and the carboxyl group of valine (-COOH) come together, forming an amide bond (-CONH-). This bond links the two amino acids together, resulting in the formation of glycine - valine.
During the formation of the peptide bond, a small molecule of water (H2O) is released as a byproduct. This process is known as a condensation reaction or dehydration synthesis. The water molecule is formed by combining the hydrogen atom from the amino group of glycine and the hydroxyl group (-OH) from the carboxyl group of valine.
So, in summary, when glycine and valine react, a peptide bond is formed between them, resulting in the production of glycine - valine. Simultaneously, a water molecule is released as a byproduct from the condensation reaction.