Search results for "Coccus"
showing 10 items of 1002 documents
Expression of Staphylococcus saprophyticus surface properties is modulated by composition of the atmosphere.
1995
Expression of two major surface proteins of Staphylococcus saprophyticus, the haemagglutinin and the Staphylococcus saprophyticus surface-associated protein (Ssp), requires carefully defined culture conditions. The Ssp is produced when bacteria are grown on agar, whereas expression of the haemagglutinin requires growth in broth. We sought to identify the environmental signals that are responsible for this modulation. Varying the pH, the osmolarity of the growth medium or the temperature did not influence expression of the proteins. In contrast, growth in an anaerobic atmosphere increased haemagglutination titres and fibronectin binding (both mediated by the haemagglutinin) but suppressed pr…
In vitro activity of LY333328, a new glycopeptide, against extracellular and intracellular vancomycin-resistant enterococci.
2000
The objectives of the study were to observe the activity of LY333328, a new semisynthetic glycopeptide, compared to that of vancomycin against six strains of Enterococcus faecium and Enterococcus faecalis, including four vancomycin-resistant strains. Bacteria ingested by polymorphonuclear leukocytes (PMN) as well as extracellular bacteria were studied using a colony count method. The activity against intracellular bacteria was tested with the drugs present in the extracellular medium, as well as after preincubating the PMN and removal of the drugs. LY333328 is active against the tested enterococci, regardless of their susceptibility to vancomycin, with MICs of 1-2 mg/l. It is bacteriostatic…
Rifampin-impregnated silicone catheters: a potential tool for prevention and treatment of CSF shunt infections.
2003
Background: Infection continues to be one of the major complications of cerebro-spinal fluid shunting procedures. Recent insights in the pathophysiological mechanism of these foreign body infections have elucidated the difficulty of achieving successful treatment without device removal. The development of a rifampin-impregnated silicone catheter yielded excellent results in infection prevention and treatment in vitro as well as in an animal model. Patients and Methods: Here, we describe the application of this device in two patients with a complicated course of shunt infection. Results: In one patient the rifampin-impregnated shunt system was implanted after external drainage to prevent fur…
New Insights Into the Skin Microbial Communities and Skin Aging
2020
Although it is well-known that human skin aging is accompanied by an alteration in the skin microbiota, we know little about how the composition of these changes during the course of aging and the effects of age-related skin microbes on aging. Using 16S ribosomal DNA and internal transcribed spacer ribosomal DNA sequencing to profile the microbiomes of 160 skin samples from two anatomical sites, the cheek and the abdomen, on 80 individuals of varying ages, we developed age-related microbiota profiles for both intrinsic skin aging and photoaging to provide an improved understanding of the age-dependent variation in skin microbial composition. According to the landscape, the microbial composi…
Profiling of Protein Degraders in Cultures of Human Gut Microbiota
2019
Unabsorbed proteins reach the colon and are fermented by the microbiota, yielding a variety of harmful metabolites. In the present study, a 16S rRNA gene survey identified the bacterial taxa flourishing in 11 batch fermentations with proteins and peptones as the sole fermentable substrates, inoculated with the feces of six healthy adults. Organic acids, ammonia, and indole resulting from protein breakdown and fermentation accumulated in all of the cultures. Analysis of differential abundances among time-points identified Enterobacteriaceae, Burkholderiaceae, and Desulfovibrionaceae (including Esherichia-Shigella, Sutterella, Parasutterella, and Bilophila) among the bacteria that especially …
Regional Variation of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Enterobacterales, Fluoroquinolone-Resistant Salmonella enterica and Methicill…
2020
Background: Antimicrobial resistance (AMR) thwarts the curative power of drugs and is a present-time global problem. We present data on antimicrobial susceptibility and resistance determinants of bacteria the WHO has highlighted as being key antimicrobial resistance concerns in Africa, to strengthen knowledge of AMR patterns in the region. Methods: Blood, stool, and urine specimens of febrile patients, aged between ≥ 30 days and ≤ 15 years and hospitalized in Burkina Faso, Gabon, Ghana, and Tanzania were cultured from November 2013 to March 2017 (Patients > 15 years were included in Tanzania). Antimicrobial susceptibility testing was performed for all Enterobacterales and Staphylococcus aur…
Interactions in dual species biofilms between Listeria monocytogenes EGD-e and several strains of Staphylococcus aureus.
2008
International audience; Six environmental isolates of Staphylococcus aureus and one collection strain were investigated for their ability to form monospecies biofilms and dual species biofilms with Listeria monocytogenes EGD-e on stainless steel coupons. All isolates were able to grow as biofilms but their ability to form monospecies biofilms differed. The population of L. monocytogenes EGD-e in dual species biofilms was not affected by the presence of S. aureus isolates except for strain CIP 53.156. The effect of L. monocytogenes EGD-e on the population of S. aureus was strain dependent: S. aureus population either increased or decreased or was not affected in the presence of L. monocytoge…
Increase of sulfite tolerance in Oenococcus oeni by means of acidic adaptation
1998
International audience; Sulfite is an antimicrobial agent used at the beginning of winemaking to avoid development of undesirable microorganisms. However, Oenococcus oeni, which is mainly responsible for the malolactic fermentation, has to grow in wine and therefore has to be resistant to sulfite. This study showed that acid-adapted cells of O. oeni survived better than non-adapted cells in the presence of a high sulfite concentration (30 mg l-1). Addition of a sub-lethal concentration of sulfite (15 mg l31) during the adaptation step in acidic medium increases the sulfite tolerance. Moreover, sulfite appeared to be able to induce a heat shocklike response. Our results suggest that pH homeo…
UV‐Vis Spectroscopy Reveals a Correlation Between Y263 and BV Protonation States in Bacteriophytochromes
2019
Red-light photosensory proteins, phytochromes, link light activation to biological functions by interconverting between two conformational states. For this, they undergo large-scale secondary and tertiary changes which follow small-scale Z to E bond photoisomerization of the covalently bound bilin chromophore. The complex network of amino acid interactions in the chromophore-binding pocket plays a central role in this process. Highly conserved Y263 and H290 have been found to be important for the photoconversion yield, while H260 has been identified as important for bilin protonation and proton transfer steps. Here, we focus on the roles these amino acids are playing in preserving the chemi…
Structural photoactivation of a full-length bacterial phytochrome
2016
Time-resolved x-ray solution scattering reveals the conformational signaling mechanism of a bacterial phytochrome.