The detection of interstellar glycine, the simplest amino acid, was reported in 2003 by Kuan and co-workers It was identified via 27 milimeter-wave lines. If the detection is confirmed, it may hold great significance for astrobiology.

Two laboratory studies have created small amino acids by applying ultraviolet light to an ice that includes a few simple molecules: water, methanol, ammonia, and hydrogen cyanide.

Amino acids consist of an -NH₂ amine group and -COOH carboxylic acid group. When an amino acid is placed in water, it changes from being neutral to have two offsetting charge centers. The acid group loses its H as a proton and becomes negative, while the basic amine group accept a proton and become positive. This is known as a zwitterion. A peptide bond can form by coupling amino acids across these acid and base sites, a form of polymerization that accounts for protein and enzyme structure.

Jan 2005 – A rebuttal paper by Snyder and co-workers disputed the detection of interstellar glycine.

Apr 2007 – Additional studies by Jones and co-workers and Cunningham and co-workers also call into question the conclusions of Kuan and co-workers.

Jun 2014 – Glycine has been moved from the list of detected molecules to the Non-Detections page.

Dec 2023 – Other studies that have unsuccessfully sought glycine include publications by Combes and co-workers (1996, Orion, Sgr B2) and Ceccarelli and co-workers (2000, IRAS 16293-2422), which pre-date the 2003 paper by Kuan et al., and more recent papers by Jiménez-Serra (2016, L1544), Jiménez-Serra (2020, IRAS 16293-2422B), Rivilla and co-workers (2023, G+0.693-0.027), and Carl and co-workers (2023, Barnard 5).