Phys.org February 13, 2024 Majority of the Bacteriophages are uncharacterized, and their hosts are unknown. A team of researchers in the US (Pacific Northwest National Laboratory, Oregon Health & Science University, Iowa State University) applied high-throughput chromosome conformation capture (Hi–C) to directly capture phage-host relationships. Some hosts had high centralities in bacterial community co-occurrence networks, suggesting phage infections have an important impact on the soil bacterial community interactions. They observed increased average viral copies per host (VPH) and decreased viral transcriptional activity following a two-week soil-drying incubation, indicating an increase in lysogenic infections. Soil drying also altered the observed phage […]
Category Archives: Bacteria
Magnetic bacteria point the way
Science Daily June 27, 2023 Magnetotactic bacteria contain magnetosomes, iron crystals wrapped in a membrane, which arrange themselves to align with the Earth’s magnetic field, causing the bacteria to travel in the direction of Earth’s magnetic field lines leading north or south. Magnetosome-producing microorganisms can sense and move toward the redox gradient. Researchers in Japan collected a deep-sea hydrothermal vent chimney. The mineralogical and geochemical characterization of the vent chimney sample showed an internal iron redox gradient. The electron microscopy of particles collected from the chimney sample revealed magnetotactic bacteria (MTB) cells with bullet-shaped magnetosomes, and there were minor occurrences […]
Magnetic bacteria: Microorganisms can help to extract dangerous heavy metals from wastewater
Phys.org May 8, 2023 Researchers in Germany purified water containing uranium using a special kind of bacteria known as magnetotactic bacteria which can accumulate dissolved heavy metal in their cell walls. The bacteria form nanoscopic magnetic crystals within the cell which are arranged like a row of beads. Each individual magnetic crystal is embedded in a protective membrane. The crystals and membrane form the magnetosome which the bacteria use to align themselves with the Earth’s magnetic field and orientate themselves in their habitat. It also makes them suitable for simple separation processes. The cell walls of magnetotactic bacteria are surrounded […]
Physics meets biology: How bacteria synchronize to build complex structures
Phys.org August 29, 2022 Observable characteristics—phenotypes—at the cellular scale underpins homeostasis and the fitness of living systems. However, how they shape properties at the population level remains poorly understood. An international team of researchers (Luxembourg, the Netherlands) found that phenotypic noise self-regulates with growth and coordinates collective structural organization, the kinetics of topological defects and the emergence of active transport around confluent colonies. They cataloged key phenotypic traits in bacteria growing under diverse conditions. The results revealed a statistically precise critical time for the transition from a monolayer biofilm to a multilayer biofilm, despite the strong noise in the cell […]
Study shows how some bacteria withstand antibiotic onslaught
Phys.org April 20, 2021 Bacteria that survive antibiotics, called persisters. Researchers at Princeton University explored how the number of DNA copies in a cell affects whether a cell persists despite exposure to DNA-damaging antibiotics called fluoroquinolones. The study confirmed the researchers’ expectation that bacteria with backup chromosomal copies of DNA proved to be persisters at a much greater rate than cells with just one copy. The experiments revealed a second and separate pathway to persistence in cells with a lone DNA copy. Unlike fully antibiotic resistant “superbugs,” persisters do not possess mutated genes; in fact, persisters are genetically identical to […]