Quorum sensing (QS) refers to the capacity of bacteria to monitor their population density and regulate gene expression accordingly: the QS-regulated processes deal with multicellular behaviors (e.g. growth and development of biofilm), horizontal gene transfer and host-microbe (symbiosis and pathogenesis) and microbe-microbe interactions. QS signaling requires the synthesis, exchange and percep...

Many Proteobacteria use acyl-homoserine lactone-mediated quorum-sensing (QS) to activate specific sets of genes as a function of cell density. QS often controls the virulence of pathogenic species, and in fact a previous study indicated that QS was important for Burkholderia mallei mouse lung infections. To gain in-depth information on the role of QS in B. mallei virulence, we constructed and c...

Die QS Software-Plattform ist die Datenbank der QS Qualität und Sicherheit GmbH. Es wird ein kurzer Überblick über den modularen Aufbau der Anwendung gegeben und wie QS, die QS-Vertragspartner, Zertifizierungsstellen und Labore auf diese zugreifen können. Abschließend wird kurz auf die Schnittstellen zu anderen Datenbank-Systemen und die Datensicherheit eingegangen.

Bacteria have been widely reported to use quorum sensing (QS) systems, which employ small diffusible metabolites to coordinate gene expression in a population density dependent manner. In Proteobacteria, the most commonly described QS signaling molecules are N-acyl-homoserine lactones (AHLs). Recent studies suggest that members of the abundant marine Roseobacter lineage possess AHL-based QS sys...

BACKGROUND Quality assurance programs in medical education are introduced to gain insight into the quality of such programs and to trigger improvements. Although of utmost importance, research on the implementation of such programs is scarce. The Dutch General Practice (GP) specialty training institutes used an implementation strategy to implement a quality system (QS), and we aimed to study th...

Glucose uptake by isolated diaphragms of both diabetic, following streptozotocin administration, and non-diabetic animals increased in presence of an oleanane-type triterpenoid saponin isolated from the roots of M. cymbalaria. Insulin release was augmented by the presence of the saponin of M. cymbalaria (1 mg/mL) in rat insulinoma cell line (RIN-5F) preexposed to adrenaline (5 microM) and nifed...

Sea cucumbers saponins are triterpenoid glycosides which exert beneficial biomedical effects. This study was performed to assess the effect of saponin extracted from sea cucumber Holothuria leucospilota (H. leucospilota) on maturation of mice oocytes and granulosa cells. The germinal vesicles oocytes were collected from 6-8 weeks old Naval Medical Research Institute (NMRI) mice ovaries, randoml...

Bacteria secrete a variety of public good exoproducts into their environment. These exoproducts are typically produced under the control of quorum sensing (QS), a signaling mechanism by which bacteria sense and respond to changes in their density. QS seems to provide an advantageous strategy to regulate these costly but beneficial exoproducts: it delays production until sufficiently high cell d...

Through production and sensing of small signal molecules, quorum sensing (QS) enables bacteria to detect changes in their density and regulate their functions accordingly. QS systems are tremendously diverse in terms of their specific sensory components, the biochemical and transport properties of signaling molecules, their target functions and the context in which QS-mediated functions are act...

Quorum Sensing (QS) drives coordinated phenotypic outcomes among bacterial populations. Its role in mediating infectious disease has led to the elucidation of numerous autoinducers and their corresponding QS signaling pathways. Among them, the Lsr (LuxS-regulated) QS system is conserved in scores of bacteria, and its signal molecule, autoinducer-2 (AI-2), is synthesized as a product of 1-carbon...