Abstract Temporal and spatial variation of soil bacterial communities was evaluated with both molecular and metabolic profiling techniques. Soil cores (20 cm deep) were taken from an upland grassland in the Scottish Borders (UK) over 3 days in July 1999, and on single days in October 1999, April 2000, and August 2000. Cores were separated into four 5-cm depths to examine vertical spatial distribution. The 0-5-, 5-10- and 10-15-cm samples represented organic horizons whilst the 15-20-cm depths were from a mineral horizon. The potential metabolic activities were analysed using BIOLOG-GN plates, whereas genotypic diversity was evaluated using molecular profiling of amplified 16S rRNA and 16S rDNA gene fragments (denaturing gradient gel electrophoresis (DGGE)). BIOLOG-GN analysis revealed decreased substrate utilisation in the lowest depths, which was coupled with changes in the DNA and RNA DGGE profiles. Seasonal variation was pronounced in the 5-10-cm and 10-15-cm organic horizons for the July samplings whilst the 15-20-cm depths appeared more stable. Potential factors influencing the observed changes in bacterial communities resulting from soil depth and sampling time are discussed.
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http://dx.doi.org/10.1111/j.1574-6941.2003.tb01043.x | DOI Listing |
Appl Environ Microbiol
January 2025
Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration, Laurel, Maryland, USA.
As a diverse and complex food matrix, the animal food microbiota and repertoire of antimicrobial resistance (AMR) genes remain to be better understood. In this study, 16S rRNA gene amplicon sequencing and shotgun metagenomics were applied to three types of animal food samples (cattle feed, dry dog food, and poultry feed). ZymoBIOMICS mock microbial community was used for workflow optimization including DNA extraction kits and bead-beating conditions.
View Article and Find Full Text PDFAppl Environ Microbiol
January 2025
Department of Earth, Environmental and Planetary Sciences, Washington University in St. Louis, St. Louis, Missouri, USA.
Microorganisms adapted to high hydrostatic pressures at depth in the oceans and within the subsurface of Earth's crust represent a phylogenetically diverse community thriving under extreme pressure, temperature, and nutrient availability conditions. To better understand the microbial function, physiological responses, and metabolic strategies at conditions requires high-pressure (HP) continuous culturing techniques that, although commonly used in bioengineering and biotechnology applications, remain relatively rare in the study of the Earth's microbiomes. Here, we focus on recent developments in the design of HP chemostats, with particular emphasis on adaptations for delivery and sampling of dissolved gases.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China.
The lunar soil samples returned by China's Chang'e-5 (CE-5) contain valuable information on geological evolutions on the Moon. Herein, by employing high-resolution time-of-flight secondary ion mass spectrometry (TOF-SIMS), five rock chip samples from the CE-5 lunar soil are characterized in-depth, which reveal micro-morphological and compositional features. From the elemental/molecular ion distribution images, minerals such as pyroxene, ilmenite, feldspar, K-rich glass, silica, and silicate minerals are identified, along with their occurrence states and distribution results.
View Article and Find Full Text PDFGout Urate Cryst Depos Dis
December 2024
Electrical and Computer Engineering Department, University of California, Los Angeles, CA 90095, USA.
Background: The gold standard for crystal arthritis diagnosis relies on the identification of either monosodium urate (MSU) or calcium pyrophosphate (CPP) crystals in synovial fluid. With the goal of enhanced crystal detection, we adapted a standard compensated polarized light microscope (CPLM) with a polarized digital camera and multi-focal depth imaging capabilities to create digital images from synovial fluid mounted on microscope slides. Using this single-shot computational polarized light microscopy (SCPLM) method, we compared rates of crystal detection and raters' preference for image.
View Article and Find Full Text PDFVirus Evol
January 2025
MRC-University of Glasgow Centre for Virus Research, The University of Glasgow, Glasgow G61 1QH, United Kingdom.
Anelloviruses are a group of small, circular, single-stranded DNA viruses that are found ubiquitously across mammalian hosts. Here, we explored a large number of publicly available human microbiome datasets and retrieved a total of 829 anellovirus genomes, substantially expanding the known diversity of these viruses. The majority of new genomes fall within the three major human anellovirus genera: , and , while we also present new genomes of the under-sampled , and genera.
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