Siderophores are potent ferric ion chelators produced by microbes like bacteria and fungi during iron stress. The objective of this study was to verify the siderophore-production in noduleforming bacteria and then to compare them with pure cultures of Rhizobium meliloti bacteria. It was achieved by inoculating nodule-forming bacteria in YEM media followed by Chrome Azurol Sulfonate (CAS) assay,...

Bacterial contaminants from commercial fuel ethanol production facilities were previously shown to form biofilms as mixed cultures under laboratory conditions. In this study, a rapid assay was developed to simultaneously compare isolates for their ability to form biofilms as pure cultures. A total of 10 strains were isolated from a dry-grind fuel ethanol plant that routinely doses with virginia...

Resistance to infection may be influenced by foreign bodies such as devices for fracture fixation. It is known that stainless steel and commercially-pure titanium have different biocompatibilities. We have investigated susceptibility to infection after a local bacterial challenge using standard 2.0 dynamic compression plates of either stainless steel or titanium in rabbit tibiae. After the woun...

The mineralization of phenanthrene in pure cultures of a Pseudomonas fluorescens strain, isolated from soil, was measured in the presence of soil humic fractions and montmorillonite. Humic acid and clay, either separately or in combination, shortened the acclimation phase. A higher mineralization rate was measured in treatments with humic acid at 100 microg/ml. Humic acid at 10 microg/ml stimul...

bacterial culturability and abundance in an alpine soil. (manuscript) isolated from alpine and forest soils. Int. Dr. F. Gich has supervised the diploma-thesis from H. Hoffelner who has contributed the alpine soil sample, the data for the ATP activity in soil slurries, the data of the preliminary tests for detachment of soil bacteria from soil particles, and has produced the MicroDrop cultures....

Dicarboxylic acids with 2-5 carbon atoms can be degraded fermentatively by pure cultures of various strictly anaerobic bacteria. The small amount of free energy released in these decarboxylations (about 20-25 kJ mol-1) is conserved as sole source of growth energy either through sodium-pumping decarboxylases or through electrogenic substrate/product transport devices. In the glutarate-fermenting...

Based on the DNA sequence of the symbiotic plasmid of Rhizobium strain NGR234, we predicted potential rearrangements generated by homologous recombination. All predicted rearrangements were identified experimentally by using a PCR-based methodology. Thus, the predicted and the actual dynamic maps of the replicon coincide. By using an approach that does not involve the introduction of exogenous ...

Three bacterial strains of marine origin were isolated during a screening for biosurfactants among n-alkane degrading microorganisms. One strain-identified as Alcaligenes sp. MM1-produced a novel glucose lipid. In the case of Arthrobacter sp. EK 1 the well-known trehalose tetraester was found as major component. From another pure culture classified as Arthrobacter sp. SI 1, extracellular emulsi...

Widespread contamination of groundwater by methyl tertiary butyl ether (MTBE) has triggered the exploration of different technologies for in situ removal of the pollutant, including biostimulation of naturally occurring microbial communities or bioaugmentation with specific microbial strains known to biodegrade the oxygenate. After laboratory studies revealed that bacterial strain PM1 rapidly a...

The thermophilic, anaerobic, propionate-oxidizing bacterial populations present in the methanogenic granular sludge in a thermophilic (55 degrees C) upflow anaerobic sludge blanket reactor were studied by cultivation and in situ hybridization analysis. For isolation of propionate-degrading microbes, primary enrichment was made with propionate as the sole energy source at 55 degrees C. After sev...