Proteins produced by the bacteria Pyrococcus furiosus contain metal atoms that enable the proteins to catalyze important chemical reactions.

Proteins with embedded metal atoms catalyze some of the more amazing feats of living chemistry including photosynthesis and metabolism. Metals are able to fill roles, most notably those that facilitate the movement of electrons, that cannot be filled by other types of atoms, somewhat analagous to how metal wires allow humans to control the flow of electricity. Researchers are only just begining to document the vast array of metalloproteins that exist in nature. Even in organisms like Pyrococcus furiosus, a marine hyperthermophile, with relatively well-described set of metal-containing proteins (i.e., its metalloproteome), only about half of these compounds are actually documented. Perhaps most surprisingly, there is recent evidence that these bacteria incorporate metal elements previously thought to have no place in the chemistry of life, such as lead, uranium, and vanadium.

References

"Metal ion cofactors afford proteins virtually unlimited catalytic potential…including respiration (iron and copper), photosynthesis (manganese) and drug metabolism (iron)...Of 343 metal peaks in chromatography fractions [from Pyrococcus furiosus], 158 did not match any predicted metalloprotein. Unassigned peaks included metals known to be used (cobalt, iron, nickel, tungsten and zinc; 83 peaks) plus metals the organism was not thought to assimilate (lead, manganese, molybdenum, uranium and vanadium; 75 peaks)" (Cvetkovic et al. 2010: 779)

"Overall, we find that much of microbial metalloproteomes remain uncharacterized. Notably, even with metals P. furiosus was known to assimilate, half of the observed peaks were unassigned." (Cvetkovic et al. 2010: 781)

Journal article
Microbial metalloproteomes are largely uncharacterizedNatureJuly 18, 2010
Aleksandar Cvetkovic, Angeli Lal Menon, Michael P. Thorgersen, Joseph W. Scott, Farris L. Poole II, Francis E. Jenney Jr, W. Andrew Lancaster, Jeremy L. Praissman, Saratchandra Shanmukh, Brian J. Vaccaro, Sunia A. Trauger, Ewa Kalisiak, Junefredo V. Apon, Gary Siuzdak, Steven M. Yannone, John A. Tainer, Michael W. W. Adams

Living System/s

Organism
Pyrococcus furiosusSpecies