The acronym (AATC) corresponds to N-Acetyl Thiazolidine 4-Carboxylic Acid, also known as Acetyl thioproline.

AATC is a precursor of Thiazolidine carboxylic acid (TCA), also known as Thioproline. It is a cyclic sulfuric amino acid with similar structure to that of proline.

At a cytoplasmic level the (AATC) is the precursor of both proline and (TCA), which is in turn the precursor for L-cysteine.


  • The disulfide bridges between two molecules of cysteine confer determinant properties on the functionality of the enzymes.
  • Cysteine is responsible for the making iron and sulfur bonds in the production of essential proteins during the mitochondrial respiration process or during photosynthesis in the plants’ chloroplast.
  • It is a precursor of sulfur metabolites necessary for development, such as antioxidant molecules like glutathione.
    Additionally, it is a precursor of molecules that help eliminate the toxic effect of some xenobiotic compounds and heavy metals.


  • Proline acts as an osmotic regulator in the cellular cytoplasm.
  • It confers a greater protection to the cell membrane.
  • It also serves as a reservoir of N in stress situations.
  • From an agricultural point of view, we can recognize these properties with a general improvement in photosynthesis and the synthesis of photoassimilates. It is also especially important in the formation of fruits, floral bouquets, homogeneity and correct post-setting maturation.
  • It also predisposes the plant to defensive conditions against certain pathogens and against certain potential toxic elements (ex: heavy metals).