콘텐츠로 건너뛰기
Merck
  • The terminal oxidase cbb3 functions in redox control of magnetite biomineralization in Magnetospirillum gryphiswaldense.

The terminal oxidase cbb3 functions in redox control of magnetite biomineralization in Magnetospirillum gryphiswaldense.

Journal of bacteriology (2014-05-06)
Yingjie Li, Oliver Raschdorf, Karen T Silva, Dirk Schüler
초록

The biomineralization of magnetosomes in Magnetospirillum gryphiswaldense and other magnetotactic bacteria occurs only under suboxic conditions. However, the mechanism of oxygen regulation and redox control of biosynthesis of the mixed-valence iron oxide magnetite [FeII(FeIII)2O4] is still unclear. Here, we set out to investigate the role of aerobic respiration in both energy metabolism and magnetite biomineralization of M. gryphiswaldense. Although three operons encoding putative terminal cbb3-type, aa3-type, and bd-type oxidases were identified in the genome assembly of M. gryphiswaldense, genetic and biochemical analyses revealed that only cbb3 and bd are required for oxygen respiration, whereas aa3 had no physiological significance under the tested conditions. While the loss of bd had no effects on growth and magnetosome synthesis, inactivation of cbb3 caused pleiotropic effects under microaerobic conditions in the presence of nitrate. In addition to their incapability of simultaneous nitrate and oxygen reduction, cbb3-deficient cells had complex magnetosome phenotypes and aberrant morphologies, probably by disturbing the redox balance required for proper growth and magnetite biomineralization. Altogether, besides being the primary terminal oxidase for aerobic respiration, cbb3 oxidase may serve as an oxygen sensor and have a further role in poising proper redox conditions required for magnetite biomineralization.

MATERIALS
제품 번호
브랜드
제품 설명

Sigma-Aldrich
Iron oxide(II,III) magnetic nanopowder, 30 nm avg. part. size (TEM), NHS ester functionalized
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size, 5 mg/mL in toluene
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size, 5 mg/mL in toluene
Sigma-Aldrich
Iron(II,III) oxide, nanopowder, 50-100 nm particle size (SEM), 97% trace metals basis
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 20 nm avg. part. size, 5 mg/mL in H2O
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size, 5 mg/mL in H2O
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size, 5 mg/mL in H2O
Sigma-Aldrich
Iron(II,III) oxide, powder, <5 μm, 95%
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 30 nm avg. part. size (TEM), PEG functionalized, 1 mg/mL Fe in H2O, dispersion
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size (TEM), amine functionalized, 1 mg/mL Fe in H2O, dispersion
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 20 nm avg. part. size, 5 mg/mL in toluene
Sigma-Aldrich
Iron(II,III) oxide, 99.99% trace metals basis
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size (TEM), PEG functionalized, 1 mg/mL Fe in H2O, dispersion
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size (TEM), amine functionalized, 1 mg/mL Fe in H2O, dispersion
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size (TEM), PEG functionalized, 1 mg/mL Fe in H2O, dispersion
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size (TEM), carboxylic acid functionalized, 5 mg/mL Fe in H2O, dispersion
Sigma-Aldrich
Iron oxide(II,III), magnetic nanoparticles solution, 30 nm avg. part. size (TEM), amine functionalized, 1 mg/mL Fe in H2O, dispersion