| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Biophys J, August 2000, p. 1085-1094, Vol. 79, No. 2


and
*Instituto de Química, Universidade de Brasília,
Brasília-DF 70919-970, Brazil;
Department of
Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee,
Wisconsin 53201 USA;
Department of Chemistry and
Biochemistry, University of Denver, Denver, Colorado 80208 USA; and
§Biophysics Research Institute, Medical College of
Wisconsin, Milwaukee, Wisconsin 53226 USA
X-band (9.1 GHz) and S-band (3.4 GHz) electron
paramagnetic resonance (EPR) spectra for particulate methane
monooxygenase (pMMO) in whole cells from Methylococcus
capsulatus (Bath) grown on 63Cu and 15N
were obtained and compared with previously reported spectra for pMMO
from Methylomicrobium album BG8. For both M. capsulatus (Bath) and M. album BG8, two nearly
identical Cu2+ EPR signals with resolved hyperfine coupling
to four nitrogens are observed. The EPR parameters for pMMO from
M. capsulatus (Bath) (g
= 2.244, A
= 185 G, and AN = 19 G for signal one; g
= 2.246, A
= 180 G, and AN = 19 G for signal two) and for pMMO from M. album BG8
(g
= 2.243, A
= 180
G, and AN = 18 G for signal one;
g
= 2.251, A
= 180
G, and AN = 18 G for signal two) are very
similar and are characteristic of type 2 Cu2+ in a square
planar or square pyramidal geometry. In three-pulse electron spin
echo envelope modulation (ESEEM) data for natural-abundance samples,
nitrogen quadrupolar frequencies due to the distant nitrogens of
coordinated histidine imidazoles were observed. The intensities of the
quadrupolar combination bands indicate that there are three or four
coordinated imidazoles, which implies that most, if not all, of the
coordinated nitrogens detected in the continuous wave spectra are from
histidine imidazoles.
Biophys J, August 2000, p. 1085-1094, Vol. 79, No. 2
© 2000 by the Biophysical Society 0006-3495/00/08/1085/10 $2.00
This article has been cited by other articles:
![]() |
D.-W. Choi, R. C. Kunz, E. S. Boyd, J. D. Semrau, W. E. Antholine, J.-I. Han, J. A. Zahn, J. M. Boyd, A. M. de la Mora, and A. A. DiSpirito The Membrane-Associated Methane Monooxygenase (pMMO) and pMMO-NADH:Quinone Oxidoreductase Complex from Methylococcus capsulatus Bath J. Bacteriol., October 1, 2003; 185(19): 5755 - 5764. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. L. Lieberman, D. B. Shrestha, P. E. Doan, B. M. Hoffman, T. L. Stemmler, and A. C. Rosenzweig Bioinorganic Chemistry Special Feature: Purified particulate methane monooxygenase from Methylococcus capsulatus (Bath) is a dimer with both mononuclear copper and a copper-containing cluster PNAS, April 1, 2003; 100(7): 3820 - 3825. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |