Characterization of a sulfite reductase from Desulfovibrio vulgaris
A low-molecular-weight (M/sub r/ = 27,200) sulfite reductase from Desulfovibrio vulgaris was studied with Moessbauer, EPR, and chemical techniques. This sulfite reductase was found to contain one siroheme and one (4Fe-4S) cluster. As purified, the siroheme is low-spin ferric (S = 1/2) which exhibits characteristic EPR resonances at g = 2.44, 2.36, and 1.77. At 150 K, the observed Moessbauer parameters, ..delta..E/sub Q/ = 2.49 +/- 0.02 mm/s and delta = 0.31 +/- 0.02 mm/s, for the siroheme are typical for low-spin ferric complexes. The (4Fe-4S) cluster is in the 2+ state. The Moessbauer parameters, ..delta..E/sub Q/ = 0.95 +/- 0.02 mm/s and delta = 0.38 +/- 0.02 mm/s, for the cluster are almost identical to those observed for the (4Fe-4S)/sup 2 +/ cluster in the hemoprotein subunit of the sulfite reductase from Escherichia coli. Similar to the hemoprotein subunit of E. coli sulfite reductase, low-temperature Moessbauer spectra of D. vulgaris sulfite reductase recorded with weak and strong applied fields also show evidence for an exchange-coupled siroheme-(4Fe-4S) unit. 31 references, 4 figures, 1 table.
- Research Organization:
- Emory Univ., Atlanta, GA
- DOE Contract Number:
- AS09-79ER10499
- OSTI ID:
- 5332045
- Journal Information:
- J. Biol. Chem.; (United States), Vol. 259:24
- Country of Publication:
- United States
- Language:
- English
Similar Records
Resonance Raman studies of Escherichia coli sulfite reductase hemoprotein. 2. Fe sub 4 S sub 4 cluster vibrational modes
Enzymatic redox chemistry: A proposed reaction pathway for the six-electron reduction of SO sub 3 sup 2 minus to S sup 2 minus by the assimilatory-type sulfite reductase from Desulfovibrio vulgaris (Hildenborough)
Related Subjects
DESULFOVIBRIO
BIOCHEMICAL REACTION KINETICS
IRON 57
UPTAKE
OXIDOREDUCTASES
MOLECULAR STRUCTURE
ELECTRON SPIN RESONANCE
MOLECULAR WEIGHT
SULFITES
BACTERIA
ENZYMES
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
IRON ISOTOPES
ISOTOPES
KINETICS
MAGNETIC RESONANCE
MICROORGANISMS
NUCLEI
OXYGEN COMPOUNDS
REACTION KINETICS
RESONANCE
STABLE ISOTOPES
SULFATE-REDUCING BACTERIA
SULFUR COMPOUNDS
550201* - Biochemistry- Tracer Techniques