Plant and soil types are usually considered as the two main drivers of the rhizosphere microbial communities. The aim of this work was to study the effect of both N availability and plant genotype on the plant associated rhizosphere microbial communities, in relation to the nutritional strategies of the plant-microbe interactions, for six contrasted Medicago truncatula genotypes. The plants wer...

In Inner Mongolia, steppe grasslands face desertification or degradation because of human over activity. One of the reasons for this condition is that croplands have been abandoned after inappropriate agricultural management. The soils in these croplands present heterogeneous environments in which conditions affecting microbial growth and diversity fluctuate widely in space and time. In this st...

Connecting molecular information directly to microbial transformation rates remains a challenge, despite the availability of molecular methods to investigate microbial biogeochemistry. By combining information on gene abundance and expression for key genes with quantitative modeling of nitrogen fluxes, we can begin to understand the scales on which genetic signals vary and how they relate to ke...

Microbial reverse electrodialysis cells (MRECs) combine power generation from salinity gradient energy using reverse electrodialysis (RED), with power generation from organic matter using a microbial fuel cell. Waste heat can be used to distill ammonium bicarbonate into high (HC) and low salt concentration (LC) solutions for use in the RED stack, but nitrogen crossover into the anode chamber mu...

For engineers, it is interesting to gain insight in the effect of control strategies on microbial communities, on their turn influencing the process behavior and its stability. This contribution assesses the influence of process dynamics on the microbial community in a biofilm reactor for nitrogen removal, which was controlled according to several strategies aiming at nitrite accumulation. The ...

Biological nitrogen fixation is an essential function of acid mine drainage (AMD) microbial communities. However, most acidophiles in AMD environments are uncultured microorganisms and little is known about the diversity of nitrogen-fixing genes and structure of nif gene cluster in AMD microbial communities. In this study, we used metagenomic sequencing to isolate nif genes in the AMD microbial...

Moisture play a crucial role in vermicomposting of pressmud (filter cake) (P). Five levels of moisture contents of pressmud (55-57%, 60-62%, 65-67%, 70-72% and 75-77%) at 31±2°C on earthworm activities (growth, reproduction and recovery rate of vermicompost) of Perionyx excavatus (Perrier)-an indigenous species and total microbial population, activity and nitrogen, phosphorous, potassium conten...

Title: Enantiomer-specific isotope analysis (ESIA) of D-and L-alanine: nitrogen isotopic hetero-and homogeneity by microbial process and chemical process. Abstract Nitrogen isotopic hetero-and homogeneity of D-α-alanine and L-α-alanine were investigated in microbial processes in the domain Bacteria and in chemical processes in symmetric organic synthesis. D-alanine is an enantiomer that is phys...

Nitrogen bioavailability is considered to limit the productivity of oceanic oligotrophic gyres, the largest biomes on Earth. In order to assess the microbial requirement for small organic nitrogen molecules in these and other waters, the microbial uptake rates of amino acids (leucine, methionine and tyrosine) and amino sugars (glucosamine and N-acetyl-glucosamine) as well as glucose were compar...

The acetylene reduction assay was used to determine nitrogenase activity in a waterlogged soil-straw system. Nitrogenase activity was related to the number of nitrogen-fixing clostridia. The patterns of respiration, microbial numbers, and nitrogenase activity indicated a change in the microbial activity at about the 8th day of incubation. This was attributed to the sequential use of the differe...