NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Cryo-Trapping the Distorted Octahedral Reaction Intermediate of Manganese Superoxide DismutaseSuperoxide dismutase protects organisms from potentially damaging oxygen radicals by catalyzing the disproportion of superoxide to oxygen and hydrogen peroxide. We report the use of cryogenic temperatures to kinetically trap the 6th ligand bound to the active site of manganese superoxide dismutase. Using cryocrystallography and synchrotron radiation, we describe at 1.55A resolution the six-coordinate, distorted octahedral geometry assumed by the active site during catalysis and compare it to the room temperature, five-coordinate trigonal-bipyramidal active site. Gateway residues Tyr34, His30 and a tightly bound water molecule are implicated in closing off the active site and blocking the escape route of superoxide during dismutation.
Document ID
20000109843
Acquisition Source
Marshall Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Borgstahl, Gloria
(National Academy of Sciences - National Research Council Huntsville, AL United States)
Snell, Edward H.
(National Academy of Sciences - National Research Council Huntsville, AL United States)
Rose, M. Franklin
Date Acquired
August 19, 2013
Publication Date
January 1, 2000
Subject Category
Inorganic, Organic And Physical Chemistry
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Available Downloads

There are no available downloads for this record.
No Preview Available