Title
Discovering Biomolecules with Huisgenase Activity: Designed Repeat Proteins as Biocatalysts for (3 + 2) Cycloadditions
Author
Iván Rivilla, Mikel Odriozola-Gimeno, Antonio Aires, Ana Gimeno, Jesús Jiménez-Barbero, Miquel Torrent-Sucarrat, Aitziber L. Cortajarena, Fernando P. Cossíosío
Year
2020
Journal
JACS
Abstract
Designed repeat proteins catalyze the 1,3-dipolar reaction between an imine and a π-deficient dipolarophile in THF solution to form unnatural nitroproline esters, a reaction that no enzyme can catalyze. NMR studies and mutation experiments show that both acidic and basic residues can catalyze the reaction. The diastereocontrol of the reaction depends on the flexibility of the protein and on the number and location of the active lysine and glutamate residues, which can participate independently or forming dyads that promote the formation of unusual diastereomeric cycloadducts. QM/MM calculations permit one to rationalize the origins of this Huisgenase activity and of its diastereocontrol.
Full Article
Instrument
J-815
Keywords
Circular dichroism, Chemical stability, Secondary structure, Kinetics, Biochemistry, Organic chemistry