Short answers, pulled from the story.
The first amino acid, asparagine, was discovered in 1806 by French chemists Louis-Nicolas Vauquelin and Pierre Jean Robiquet. They isolated this compound from asparagus, marking the beginning of the scientific understanding of organic compounds containing both amine and carboxylic acid groups.
All chiral proteogenic amino acids possess the L configuration, referring to their left-handed enantiomers. This specific orientation is a fundamental requirement for life, while D-amino acids are found primarily in bacterial envelopes or as neuromodulators like D-serine.
Threonine was the final of the twenty common amino acids to be discovered, identified in 1935 by William Cumming Rose. He also established the minimum daily requirements for optimal growth during this period of chemical research.
There are 22 amino acids that get naturally incorporated into polypeptides, known as proteinogenic amino acids. Of these, 20 are encoded by the universal genetic code, while the remaining two, selenocysteine and pyrrolysine, are incorporated by unique synthetic mechanisms.
In the Urey-Miller experiment, the passage of an electric arc through a mixture of methane, hydrogen, and ammonia produced a large number of amino acids. This demonstrated that simple precursors could generate complex organic molecules under conditions simulating the early Earth.