title: A comparison of the sorption reactivity of bacteriogenic and mycogenic Mn oxide nanoparticles.
abstract: Biogenic MnO2 minerals affect metal fate and transport in natural and engineered systems by strongly sorbing metals ions. The ability to produce MnO2 is widely dispersed in the microbial tree of life, leading to potential differences in the minerals produced by different organisms. In this study, we compare the structure and reactivity of biogenic Mn oxides produced by the biofilm-forming bacterium Pseudomonas putida GB-1 and the white-rot fungus Coprinellus sp. The rate of Mn(II) oxidation, and thus biomineral production, was 45 times lower for Coprinellus sp. (5.1 × 10(-2) mM d(-1)) than for P. putida (2.32 mM d(-1)). Both organisms produced predominantly Mn(IV) oxides with hexagonal-sheet symmetry, low sheet stacking, small particle size, and Mn(II/III) in the interlayer. However, we found that mycogenic MnO2 could support a significantly lower quantity of Ni sorbed via inner-sphere coordination at vacancy sites than the bacteriogenic MnO2: 0.09 versus 0.14 mol Ni mol(-1) Mn. In addition, 50-100% of the adsorbed Ni partitioned to the MnO2, which accounts for less than 20% of the sorbent on a mass basis. The vacancy content, which appears to increase with the kinetics of MnO2 precipitation, exerts significant control on biomineral reactivity.
authors: †Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, Switzerland, 1015.|‡Department of Soil Science, North Carolina State University, Raleigh, North Carolina 27695-7619, United States.
authors: Boris
authors: B
authors: Droz
authors: †Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, Switzerland, 1015.
authors: Naomi
authors: N
authors: Dumas
authors: ‡Department of Soil Science, North Carolina State University, Raleigh, North Carolina 27695-7619, United States.
authors: Owen W
authors: OW
authors: Duckworth
authors: †Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, Switzerland, 1015.
authors: Jasquelin
authors: J
authors: Peña
mesh_terms: D000327:Adsorption; D000363:Agaricales / Q000254:growth & development / Q000378:metabolism*; D018533:Biomass; D007700:Kinetics; D017895:Manganese Compounds / Q000737:chemistry*; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D016958:Pseudomonas putida / Q000254:growth & development / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D009532:Nickel; C016552:manganese dioxide