A dopamine-based biosynthetic pathway produces decarboxylated betalains in Chenopodium quinoa.

Betalains are the nitrogenous pigments that replace anthocyanins in the plant order Caryophyllales. Here, we describe unconventional decarboxylated betalains in quinoa (Chenopodium quinoa) grains. Decarboxylated betalains are derived from a previously unconsidered activity of the 4,5-DOPA-extradiol-dioxygenase enzyme (DODA), which has been identified as the key enzymatic step in the established biosynthetic pathway of betalains.

First Betalain-Producing Bacteria Break the Exclusive Presence of the Pigments in the Plant Kingdom.

The biosynthesis of antioxidant pigments, namely, betalains, was believed to be restricted to Caryophyllales plants. This paper changes this paradigm, and enzyme mining from bacterial hosts promoted the discovery of bacterial cultures producing betalains. The spectrum of possible sources of betalain pigments in nature is broadened by our description of the first betalain-forming bacterium, The enzyme-specific step is the extradiol cleavage of the precursor amino acid l-dihydroxyphenylalanine (l-DOPA) to form the structural unit betalamic acid.