BioDry: An Inexpensive, Low-Power Method to Preserve Aquatic Microbial Biomass at Room Temperature.

This report describes BioDry (patent pending), a method for reliably preserving the biomolecules associated with aquatic microbial biomass samples, without the need of hazardous materials (e.g. liquid nitrogen, preservatives, etc.

Spatial distribution of an uranium-respiring betaproteobacterium at the Rifle, CO field research site.

The Department of Energy's Integrated Field-Scale Subsurface Research Challenge Site (IFRC) at Rifle, Colorado was created to address the gaps in knowledge on the mechanisms and rates of U(VI) bioreduction in alluvial sediments. Previous studies at the Rifle IFRC have linked microbial processes to uranium immobilization during acetate amendment. Several key bacteria believed to be involved in radionuclide containment have been described; however, most of the evidence implicating uranium reduction with specific microbiota has been indirect.

Bacterial genome replication at subzero temperatures in permafrost.

Microbial metabolic activity occurs at subzero temperatures in permafrost, an environment representing ∼25% of the global soil organic matter. Although much of the observed subzero microbial activity may be due to basal metabolism or macromolecular repair, there is also ample evidence for cellular growth. Unfortunately, most metabolic measurements or culture-based laboratory experiments cannot elucidate the specific microorganisms responsible for metabolic activities in native permafrost, nor, can bulk approaches determine whether different members of the microbial community modulate their responses as a function of changing subzero temperatures.

Growth phase and elemental stoichiometry of bacterial prey influences ciliate grazing selectivity.

Protozoa are known to selectively graze bacteria and can differentiate prey based on size and viability, but less is known about the effects of prey cellular composition on predator selectivity. We measured the effect of growth phase and elemental stoichiometry of Escherichia coli on grazing by two ciliates, Euplotes vannus and Cyclidium glaucoma. Bacterial cells of a single strain were transformed with green and red fluorescent protein and harvested from culture at differing growth stages.