Amino Acids in the Universe

What is the role played by amino acids in the chemistry of the interstellar medium and the emergence of life on the early Earth? Are they really the primary key compounds as free amino acids? Is their presence or absence in the interstellar medium a significant problem? How to get an amino acid sample with an enantiomeric excess on the early Earth or ISM? How to increase the enantiomeric excess to have pure enantiomers? All these questions have received partial answers but they remain open and probably they will still be open for several more decades