In this study, a potentiometric titration was performed to investigate the surface acid–base properties of Pseudomonas pseudoalcaligenes isolated from activated sludge. Batch sorption as a function of pH was performed to explain the sorption behaviour of Cu(II) and Pb(II) ions onto the bacterial surface. The surface complexation approach in the frame of constant capacitance model was applied to...

The variation in bacterial, fungal and total microbial biomass and activity was studied together with the abundance of soil nematodes and microarthropods after the addition of substrates differing in nitrogen availability to a soddy-podzolic soil. The experiments were carried out in microcosms with native and defaunated soil to evaluate stimulatory and suppressive effects of the microfauna on s...

The balance of production in any ecosystem is dependent on the flow of limiting nutrients into either the autotrophic or heterotrophic components of the food web. To understand one of the important controls on the flow of inorganic nutrients between phytoplankton and bacterioplankton in lakes, we manipulated dissolved organic carbon (DOC) in two lakes of different trophic status. We hypothesize...

The effects of natural sunlight and microbial decomposition on DOC, DON, and DOP were investigated along the salinity gradient of a temperate coastal plain estuary. The impact of sunlight-irradiated DOM on bacterial properties (bacterial abundance, production, bacterial growth efficiency [BGE]) was also followed. Surface-water light levels resulted in no detectable abiotic production of NH4 or ...

INTRODUCTION Bacterial viruses (phages) have been used successfully in the treatment of animal and human bacterial infections. This study examined the potential use of phage therapy against Pseudomonas aeruginosa strain PA14 biofilms in a root canal model. METHODS Part 1: The 24-hour and 96-hour PA14 biofilms grown in microplates were treated with phages identified as possessing potential bio...

Biomass content and incorporation rates for carbon (C) and phosphorus (P) in microbial plankton in the Bay of Aarhus were investigated during a 1 week period. Samples taken daily at a fixed station, as well as during a diel cycle, allowed comparison of the water masses above, in and below the pycnocline, and in influxes of different water masses. The coupling between the activity of phytoplankt...

Natural remediation of oil spills is catalyzed by complex microbial consortia. Here we took a whole-community approach to investigate bacterial incorporation of petroleum hydrocarbons from a simulated oil spill. We utilized the natural difference in carbon isotopic abundance between a salt marsh ecosystem supported by the 13C-enriched C4 grass Spartina alterniflora and 13C-depleted petroleum to...

Neisseria meningitidis is a commensal of human nasopharynx. In some circumstances, this bacteria can invade the bloodstream and, after crossing the blood brain barrier, the meninges. A filamentous phage, designated MDAΦ for Meningococcal Disease Associated, has been associated with invasive disease. In this work we show that the prophage is not associated with a higher virulence during the bloo...

Copper contamination on China's arable land could pose severe economic, ecological and healthy consequences in the coming decades. As the drivers in maintaining ecosystem functioning, the responses of soil microorganisms to long-term copper contamination in different soil ecosystems are still debated. This study investigated the impacts of copper gradients on soil bacterial communities in two a...