Article

Computational improvements reveal great bacterial diversity and high metal toxicity in soil

Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87501, USA.
Science (Impact Factor: 31.48). 09/2005; 309(5739):1387-90. DOI: 10.1126/science.1112665
Source: PubMed

ABSTRACT The complexity of soil bacterial communities has thus far confounded effective measurement. However, with improved analytical methods, we show that the abundance distribution and total diversity can be deciphered. Reanalysis of reassociation kinetics for bacterial community DNA from pristine and metal-polluted soils showed that a power law best described the abundance distributions. More than one million distinct genomes occurred in the pristine soil, exceeding previous estimates by two orders of magnitude. Metal pollution reduced diversity more than 99.9%, revealing the highly toxic effect of metal contamination, especially for rare taxa.

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Available from: Murray Wolinsky, Jul 30, 2015
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    • "With an estimated total number of 4e6 Â 10 30 cells, prokaryotes are the most diverse and abundant cellular life forms on Earth [190]. For example, 1 g of soil may contain up to 10 9 bacterial cells [190], and mathematical treatment of the data suggests that 10 6 distinct prokaryotic taxa may be present [27] [54] [184]. Prokaryotes are small and undergo a rapid cell cycle coupled with a metabolic versatility that enables them to be key players in the functioning of all ecosystems, even the most extreme ones [190]. "
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    • "In addition to decomposition of natural organic matter, microorganisms are also capable of catalyzing oxidation and reduction reactions, and thus can influence the biogeochemical cycling of key metals and elements in the environment. It is estimated that in a single gram of a soil, there are *10 9 cells and over 10 6 individual taxa, reflecting the vast functional and taxonomic diversity in soil environments (Curtis and Sloan 2005; Gans et al. 2005). Thus the soil microbial community is one of the most diverse prokaryotic systems yet studied, which can pose technical challenges in detecting and isolating less numerous taxa (Delmont et al. 2011). "
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    • "Soil microbial communities might display the highest level of bacterial diversity of any environment with a single gram reported to contain about a billion cells making up thousands to millions of different taxa (Torsvik et al., 2002; Gans et al., 2005; Roesch et al., 2007). "
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