Anaerobic, Nitrate-Dependent Oxidation of Pyrite Nanoparticles by Thiobacillus denitrificans

Bosch, Julian; Lee, Keun-Young; Jordan, Guntram; Kim, Kyoung-Woong and Meckenstock, Rainer U. (2012): Anaerobic, Nitrate-Dependent Oxidation of Pyrite Nanoparticles by Thiobacillus denitrificans. In: Environmental Science and Technology, Vol. 46, No. 4: pp. 2095-2101

Abstract

Pyrite is a key mineral in the global biogeochemical cycles of sulfurand iron, yet its anaerobic microbial oxidation has eluded geochemistsand microbiologists for decades. Recent reports indicated that anaerobicoxidation of pyrite is occurring, but the mechanism remains unclear.Here, we provide evidence for the capability of Thiobacillusdenitrificans to anaerobically oxidize a putatively nanosized pyriteparticle fraction with nitrate as electron acceptor. Nanosized pyritewas readily oxidized to ferric iron and sulfate with a rate of 10.1 mu Mh(-1). The mass balance of pyrite oxidation and nitrate reductionrevealed a closed recovery of the electrons. This substantiates afurther “missing lithotrophy” in the global cycles of sulfur andiron and emphasizes the high reactivity of nanominerals in theenvironment.

• Item Type: Journal article
• Faculties: Geosciences > Department of Earth and Environmental Sciences > Crystallography and Materials Science
• Subjects: 500 Science > 550 Earth sciences and geology
• Language: English