@article {3121,
	title = {Centimeter-long electron transport in marine sediments via conductive minerals.},
	journal = {ISME J},
	volume = {9},
	year = {2015},
	month = {2015 Feb},
	pages = {527-31},
	abstract = {<p>Centimeter-long electron conduction through marine sediments, in which electrons derived from sulfide in anoxic sediments are transported to oxygen in surficial sediments, may have an important influence on sediment geochemistry. Filamentous bacteria have been proposed to mediate the electron transport, but the filament conductivity could not be verified and other mechanisms are possible. Surprisingly, previous investigations have never actually measured the sediment conductivity or its basic physical properties. Here we report direct measurements that demonstrate centimeter-long electron flow through marine sediments, with conductivities sufficient to account for previously estimated electron fluxes. Conductivity was lost for oxidized sediments, which contrasts with the previously described increase in the conductivity of microbial biofilms upon oxidation. Adding pyrite to the sediments significantly enhanced the conductivity. These results suggest that the role of conductive minerals, which are more commonly found in sediments than centimeter-long microbial filaments, need to be considered when modeling marine sediment biogeochemistry.</p>},
	keywords = {Electron Transport, Geologic Sediments, Iron, Minerals, Oxidation-Reduction, Sulfides},
	issn = {1751-7370},
	doi = {10.1038/ismej.2014.131},
	author = {Malvankar, Nikhil S and King, Gary M and Lovley, Derek R}
}
@article {746,
	title = {Comparative bacterial diversity in recent Hawaiian volcanic deposits of different ages.},
	journal = {FEMS Microbiol Ecol},
	volume = {60},
	year = {2007},
	month = {2007 Apr},
	pages = {60-73},
	abstract = {Volcanic activity creates new landforms that can change dramatically over time as a consequence of biotic succession. Nonetheless, volcanic deposits present severe constraints for microbial colonization and activity. We have characterized bacterial diversity on four recent deposits at Kilauea volcano, Hawaii (KVD). Much of the diversity was either closely related to uncultured organisms or distinct from any reported 16S rRNA gene sequences. Diversity indices suggested that diversity was highest in a moderately vegetated 210-year-old ash deposit (1790-KVD), and lowest for a 79-year-old lava flow (1921-KVD). Diversity for a 41-year-old tephra deposit (1959-KVD) and a 300-year-old rainforest (1700-KVD) reached intermediate values. The 1959-KVD and 1790-KVD communities were dominated by Acidobacteria, Alpha- and Gammaproteobacteria, Actinobacteria, Cyanobacteria, and many unclassified phylotypes. The 1921-KVD, an unvegetated low pH deposit, was dominated by unclassified phylotypes. In contrast, 1700-KVD was primarily populated by Alphaproteobacteria with very few unclassified phylotypes. Similar diversity indices and levels of trace gas flux were found for 1959-KVD and 1790-KVD; however, statistical analyses indicated significantly different communities. This study not only showed that microorganisms colonize recent volcanic deposits and are able to establish diverse communities, but also that their composition is governed by variations in local deposit parameters.},
	keywords = {Bacteria, DNA, Bacterial, Ecosystem, Genes, rRNA, Genetic Variation, Hawaii, Molecular Sequence Data, Phylogeny, Polymerase Chain Reaction, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Soil Microbiology, Time Factors, Volcanic Eruptions},
	issn = {0168-6496},
	doi = {10.1111/j.1574-6941.2006.00253.x},
	author = {Gomez-Alvarez, Vicente and King, Gary M and N{\"u}sslein, Klaus}
}
