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Physical Sciences and Mathematics Commons

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Chemistry

Selected Works

2012

Catalysis

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

36 Degrees Step Size Of Proton-Driven C-Ring Rotation In Fof1-Atp Synthase, Monika Düser, Nawid Zarrabi, Daniel Cipriano, Stefan Ernst, Gary Glick, Stanley Dunn, Michael Börsch Oct 2012

36 Degrees Step Size Of Proton-Driven C-Ring Rotation In Fof1-Atp Synthase, Monika Düser, Nawid Zarrabi, Daniel Cipriano, Stefan Ernst, Gary Glick, Stanley Dunn, Michael Börsch

Stanley D Dunn

Synthesis of adenosine triphosphate ATP, the 'biological energy currency', is accomplished by F(o)F(1)-ATP synthase. In the plasma membrane of Escherichia coli, proton-driven rotation of a ring of 10 c subunits in the F(o) motor powers catalysis in the F(1) motor. Although F(1) uses 120 degrees stepping during ATP synthesis, models of F(o) predict either an incremental rotation of c subunits in 36 degrees steps or larger step sizes comprising several fast substeps. Using single-molecule fluorescence resonance energy transfer, we provide the first experimental determination of a 36 degrees sequential stepping mode of the c-ring during ATP synthesis.


Polycyclic Aromatic Triptycenes: Oxygen Substitution Cyclization Strategies, Brett Vanveller, Derek J. Schipper, Timothy M. Swager Apr 2012

Polycyclic Aromatic Triptycenes: Oxygen Substitution Cyclization Strategies, Brett Vanveller, Derek J. Schipper, Timothy M. Swager

Brett VanVeller

The cyclization and planarization of polycyclic aromatic hydrocarbons with concomitant oxygen substitution was achieved through acid catalyzed transetherification and oxygen-radical reactions. The triptycene scaffold enforces proximity of the alcohol and arene reacting partners and confers significant rigidity to the resulting π-system, expanding the tool set of iptycenes for materials applications.