Electron transfer coupled to Mn(II) oxidation in two deep-sea Pacific Ocean isolates

Conference · Mon Jan 01 00:00:00 EST 1979

OSTI ID:5826030

Arcuri, E. J.; Ehrlich, H. L.

Recent work conducted to elucidate the electron transport pathway involved in Mn(II)-oxidation by Oceanospirillum strains BIII 45 and BIII 82 was reviewed and new information concerned with the cellular organization of the Mn(II)-oxidoreductase system in these organisms was presented. The presence of both b-type and c-type cytochromes was found in both strains. Cytochromes found were predominantly assoiated with the membrane fraction. A small amount was found in the periplasmic fraction. No cytochromes were found in the intracellular fraction. Mn(II) was able to reduce the c-type cytochrome only when membranes were combined with either periplasmic or intracellular fractions. An hypothesis for the mechanism of Mn(II) oxidation (similar to FeII oxidation) is presented. In this mechanism, rusticyanin is the primary electron acceptor. The oxidized rusticyanin then reduces a c-type cytochrome in the periplasmic space. The reduced cytochrome c then reduces a membrane a-type cytochrome oxidase. This would explain the necessity of combining fractions to obtain cytochrome reduction on Mn(II) addition.

• Research Organization: Oak Ridge National Lab., TN (USA); Rensselaer Polytechnic Inst., Troy, NY (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5826030
• Report Number(s): CONF-790858-1
• Resource Relation: Conference: 4. international symposium on environmental biogeochemistry, Canberra, Australia, 27 Aug 1979
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ELECTRON TRANSFER
BIOLOGICAL PATHWAYS
OXIDOREDUCTASES
BIOCHEMICAL REACTION KINETICS
BACTERIA
CELL MEMBRANES
CYTOCHROME OXIDASE
CYTOCHROMES
MANGANESE
OXIDATION
CELL CONSTITUENTS
CHEMICAL REACTIONS
ELEMENTS
ENZYMES
KINETICS
MEMBRANES
METALS
MICROORGANISMS
OXIDASES
PIGMENTS
REACTION KINETICS
TRANSITION ELEMENTS
550200* - Biochemistry