Microorganisms capable of aerobic respiration on ferrous ions are spread throughout eubacterial and archaebacterial phyla. Phylogenetically distinct organisms were shown to express spectrally distinct redox#x2010;active biomolecules during autotrophic growth on soluble iron. A new iron#x2010;oxidizing eubacterium, designated as strain Funis, was investigated. Strain Funis was judged to be different from other known iron#x2010;oxidizing bacteria on the bases of comparative lipid analyses, 16S rRNA sequence analyses, and cytochrome composition studies. When grown autotrophically on ferrous ions, Funis produced conspicuous levels of a novel acid#x2010;stable, acid#x2010;soluble yellow cytochrome with a distinctive absorbance peak at 579 nm in the reduced state.
展开▼