Image credit: Motoyama, T., Nakano, S., Hasebe, F., Miyata, R., Kumazawa, S., Miyoshi, N., Ito, S., Chemoenzymatic synthesis of 3-ethyl-2,5-dimethylpyrazine by L-threonine 3-dehydrogenase and 2-amino-3-ketobutyrate CoA ligase/L-threonine aldolase. Communications Chemistry 4, Article number: 108 (2021). DOI: 10.1038/s42004-021-00545-8 Figure 5. A.

Motoyama et al reports that the bacterial operons for L-threonine 3-dehydrogenase (TDH) and 2-amino-3-ketobutyrate CoA ligase (KBL) are capable of producing 3-ethyl-2,5-dimethylpyrazine (EDMP) only using L-threonine in the Nature Research Journal, Communications Chemistry 4, Article number 108, published 16 July 2021. Crystals of CnKBL were grown using Crystal Screen and Index with the use of the Additive Screen. The crystal structures revealed a possible catalytic residue for L-threonine aldolase-like activity.

The implications of the findings may lead to more pathways in the production of alkylpyrazines for use in medicine, food, and cosmetics.