Microbial Alchemy

See allHide authors and affiliations

Science  27 Jul 2001:
Vol. 293, Issue 5530, pp. 577
DOI: 10.1126/science.293.5530.577b

Submarine thermal venting systems are a cauldron of exotic life forms. They have considerable economic potential, because extant and ancient hydrothermal systems are foci of precious metal deposits. Bacteria are well known to be associated with economically important iron and zinc deposits, and living bacterial mats on and within hydrothermal vents are known to contain high concentrations of silver salts.

Kashefi et al. have now shown that, in vitro, several species of thermophilic ironreducing Archaea and Bacteria can precipitate purple colloidal gold onto their cell surfaces from 1.5 mM Au(III) bicarbonate buffered solution. Generally, hydrogen is the preferred electron donor, at least for the archaean Pyrobaculum islandicum and the bacterium Thermotoga maritima, but not all Fe(III) microorganisms reduce Au(III), which suggests that a specific hydrogenase at the bacterial cell surface may be responsible. — CA

Appl. Environ. Microbiol. 67, 3275 (2001).

Navigate This Article