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Article Abstract

The B cofactors instill a natural curiosity regarding the primordial selection and evolution of their corrin ligand. Surprisingly, this important natural macrocycle has evaded molecular scrutiny, and its specific role in predisposing the incarcerated cobalt ion for organometallic catalysis has remained obscure. Herein, we report the biosynthesis of the cobalt-free B corrin moiety, hydrogenobyric acid (Hby), a compound crafted through pathway redesign. Detailed insights from single-crystal X-ray and solution structures of Hby have revealed a distorted helical cavity, redefining the pattern for binding cobalt ions. Consequently, the corrin ligand coordinates cobalt ions in desymmetrized "entatic" states, thereby promoting the activation of B -cofactors for their challenging chemical transitions. The availability of Hby also provides a route to the synthesis of transition metal analogues of B .

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6771967PMC
http://dx.doi.org/10.1002/anie.201904713DOI Listing

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Article Synopsis
  • - Green hydrogen is a promising clean energy source derived from water, efficiently storing electrical energy from renewable sources like wind and solar, but direct production from neutral water is difficult due to low proton concentration.
  • - Researchers developed three new molecular electrodes using cobalt-based electrocatalysts with different ligands (porphyrin, phthalocyanine, and corrin) on modified graphite, with the Co-porphyrin electrode showing the highest efficiency for water reduction.
  • - The Co-porphyrin electrode demonstrated significant improvements in hydrogen production potential over time and maintained consistent hydrogen generation during testing, with the best turnover frequency noted among the three electrodes tested.
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