Isolation, Sequencing, and Characterization of the Cytochrome bo Operon from Vitreoscilla

Abstract

The entire operon encoding the sodium pumping cytochrome bo from the bacterium Vitreoscilla was isolated and sequenced, and this sequence was analyzed by blast and hydropathy plots. There are fairly similar phylogenetic relationships which apply to all five proteins, but overall greater similarity to members of the gamma subdivision than the beta subdivision of the Proteobacteria. Hydropathy plots of all five Cyo proteins show near identity with those of the corresponding E. coli subunits, indicating that the similarity extends from sequence to structure. The operon appears to have a typical Shine-Dalgarno sequence, an E. coli-like promoter, and several possible binding sites for regulatory proteins. The Vitreoscilla Cyo B subunit (the probable Na+ pump) is almost identical to E. coli Cyo B at 18 key amino acids; thus, there are no obvious changes in Vitreoscilla Cyo B that hint at the details of its Na+ pumping ability.

Complete Genome Sequence of Vitreoscilla sp. Strain C1, Source of the First Bacterial Hemoglobin

“…Discrepancies were curated manually with Artemis 16.0.0 (16) based on the sum of evidence presented by the individual predictors. The previously determined sequences of the VHb (17) and cytochrome bo loci (18) were confirmed.…”

The proton pumping bo oxidase from Vitreoscilla

“…The Vitreoscilla cytochrome cyo operon has been sequenced earlier 35 , showing that it encodes for subunits I-IV and the protoheme IX farnesyltransferase that is important for heme o biosynthesis 36,37 . The Vitreoscilla bo oxidase ( vbo 3 ) was previously shown to be structurally similar to the E. coli enzyme 31 .…”