TY - JOUR
T1 - Isolation and immunocytochemical location of the nitrite-oxidizing system in Nitrospira moscoviensis
AU - Spieck, E.
AU - Ehrich, Silke
AU - Aamand, Jens
AU - Bock, Eberhard
PY - 1998/2
Y1 - 1998/2
N2 - A membrane-associated nitrite-oxidizing system of Nitrospira moscoviensis was isolated from heat-treated membranes. The four major proteins of the enzyme fraction had apparent molecular masses of 130, 62, 46, and 29 kDa, respectively. The nitrite-oxidizing activity was dependent on the presence of molybdenum. In contrast to the nitrite oxidoreductase of Nitrobacter hamburgensis X14, the activity of the nitrite-oxidizing system of Ns. moscoviensis increased when solubilized by heat treatment. Electron microscopy of the purified enzyme revealed uniform particles with a size of approximately 7 x 9 nm. SDS-immunoblotting analysis of crude extracts showed that the monoclonal antibodies Hyb 153-3, which recognize the β-subunit of the nitrite oxidoreductase from Nitrobacter, reacted with a protein of 50 kDa in Ns. moscoviensis. This protein corresponded to the protein of 46 kDa of the purified enzyme and contained a b-type cytochrome. Using electron microscopic immunocytochemistry and the monoclonal antibodies Hyb 153-3, the nitrite-oxidizing system of Ns. moscoviensis was shown to be located in the periplasmic space. Here a periodic arrangement of membrane-associated particles was found on the outside of the cytoplasmic membrane in the form of a hexagonal pattern. It is supposed that these particles represent the nitrite-oxidizing system in Nitrospira.
AB - A membrane-associated nitrite-oxidizing system of Nitrospira moscoviensis was isolated from heat-treated membranes. The four major proteins of the enzyme fraction had apparent molecular masses of 130, 62, 46, and 29 kDa, respectively. The nitrite-oxidizing activity was dependent on the presence of molybdenum. In contrast to the nitrite oxidoreductase of Nitrobacter hamburgensis X14, the activity of the nitrite-oxidizing system of Ns. moscoviensis increased when solubilized by heat treatment. Electron microscopy of the purified enzyme revealed uniform particles with a size of approximately 7 x 9 nm. SDS-immunoblotting analysis of crude extracts showed that the monoclonal antibodies Hyb 153-3, which recognize the β-subunit of the nitrite oxidoreductase from Nitrobacter, reacted with a protein of 50 kDa in Ns. moscoviensis. This protein corresponded to the protein of 46 kDa of the purified enzyme and contained a b-type cytochrome. Using electron microscopic immunocytochemistry and the monoclonal antibodies Hyb 153-3, the nitrite-oxidizing system of Ns. moscoviensis was shown to be located in the periplasmic space. Here a periodic arrangement of membrane-associated particles was found on the outside of the cytoplasmic membrane in the form of a hexagonal pattern. It is supposed that these particles represent the nitrite-oxidizing system in Nitrospira.
KW - Hexagonal pattern
KW - Membrane-associated enzyme
KW - Monoclonal antibodies
KW - Nitrite-oxidizing system
KW - Nitrospira moscoviensis
KW - Periplasmic space
KW - Post-embedding labeling
KW - Immunoassay
KW - Ammonium
KW - Oxidation
UR - http://www.scopus.com/inward/record.url?scp=0031951770&partnerID=8YFLogxK
U2 - 10.1007/s002030050565
DO - 10.1007/s002030050565
M3 - Article
AN - SCOPUS:0031951770
SN - 0302-8933
VL - 169
SP - 225
EP - 230
JO - Archives of Microbiology
JF - Archives of Microbiology
IS - 3
ER -