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Abstract This study investigates dioxygen binding and 2‐oxoglutarate (2OG) coordination by two model non‐heme FeII/2OG enzymes: a class 7 histone demethylase (PHF8) that catalyzes the hydroxylation of its H3K9me2 histone substrate leading to demethylation reactivity and the ethylene‐forming enzyme (EFE), which catalyzes two competing reactions of ethylene generation and substratel‐Arg hydroxylation. Although both enzymes initially bind 2OG by using anoff‐line2OG coordination mode, in PHF8, the substrate oxidation requires a transition to anin‐linemode, whereas EFE is catalytically productive for ethylene production from 2OG in theoff‐linemode. We used classical molecular dynamics (MD), quantum mechanics/molecular mechanics (QM/MM) MD and QM/MM metadynamics (QM/MM‐MetD) simulations to reveal that it is the dioxygen binding process and, ultimately, the protein environment that control the formation of thein‐lineFeIII‐OO⋅−intermediate in PHF8 and theoff‐lineFeIII‐OO⋅−intermediate in EFE.
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This content will become publicly available on September 1, 2026
On the Evidence for the Violation of the Equivalence Principle in Disk Galaxies
We examine the claimed observations of a gravitational external field effect (EFE) reported by Chae et al. We show that observations suggestive of the EFE can be interpreted without violating Einstein’s equivalence principle, namely from known correlations between the morphology, the environment, and dynamics of galaxies. While Chae et al.’s analysis provides a valuable attempt at a clear test of modified Newtonian dynamics, an evidently important topic, a re-analysis of the observational data does not permit us to confidently assess the presence of an EFE or to distinguish this interpretation from that proposed in this article.
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- Award ID(s):
- 1847771
- PAR ID:
- 10611514
- Publisher / Repository:
- Particles
- Date Published:
- Journal Name:
- Particles
- Volume:
- 8
- Issue:
- 3
- ISSN:
- 2571-712X
- Page Range / eLocation ID:
- 65
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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