Rhodobacter sphaeroides ATCC 17029

Rhodobacter sphaeroides ATCC 17029 (Bacteria, 4.4 Mb): Metabolically diverse, grows in wide variety of conditions; photosynthetic, providing fundamental insights into light-driven, renewable-energy production; can detoxify metal oxides, useful in bioremediation.

Each of the Rhodobacter sphaeroides strains; 2.4.1, ATCC 17025 and ATCC 17029 have a large ~3.0 Mb chromosome and a small ~0.9 - 1.2 Mb chromosome. Comparative optical mapping studies have shown that in terms of size and physical map structure, the large chromosomes in these strains is relatively stable, whereas the smaller chromosomes are much more variable. By comparing the genomes of these three strains we aim to determine what factors lead to chromosome and genome stability/instability. Addressing this question will give us a better understanding of the mechanisms involved in genome evolution and speciation.

Like R.sphaeroides 2.4.1 strain examining the genomes of ATCC 17025 and 17029 will give us a greater understanding of the structural and functional aspects of the light reactions of photosynthesis, mechanisms of CO2 fixation, nitrogen fixation, cytochrome diversity and electron transport systems. Individually and in combination, these areas have been and will continue to be major areas of interest to the DOE.

In addition, R. sphaeroides has been shown to be able to detoxify a number of metal oxides and oxyanions and is the subject of ongoing studies in this area, in keeping with the direct mission of the DOE in bioremediation. Additional investigations over many years have led to increased knowledge of tetrapyrrole and carotenoid biosynthesis, which have broad applicability.

Nereng, K.S. and S. Kaplan Genomic complexity among strains of the facultative photoheterotrophic bacterium Rhodobacter sphaeroides. J Bacteriol. 1999 Mar;181(5):1684-8.