AUTHOR=Michlits Hanna , Valente Nina , Mlynek Georg , Hofbauer Stefan TITLE=Initial Steps to Engineer Coproheme Decarboxylase to Obtain Stereospecific Monovinyl, Monopropionyl Deuterohemes JOURNAL=Frontiers in Bioengineering and Biotechnology VOLUME=9 YEAR=2022 URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2021.807678 DOI=10.3389/fbioe.2021.807678 ISSN=2296-4185 ABSTRACT=

The oxidative decarboxylation of coproheme to form heme b by coproheme decarboxylase is a stereospecific two-step reaction. In the first step, the propionate at position two (p2) is cleaved off the pyrrole ring A to form a vinyl group at this position. Subsequently, the propionate at position four (p4) on pyrrole ring B is cleaved off and heme b is formed. In this study, we attempted to engineer coproheme decarboxylase from Corynebacterium diphtheriae to alter the stereospecificity of this reaction. By introducing a tyrosine residue in proximity to the propionate at position 4, we were able to create a new radical center in the active site. However, the artificial Tyr183• radical could not be shown to catalyze any decarboxylation.