Search results for "microbiologie"
showing 10 items of 42 documents
La fermentation en milieu solide : une innovation de rupture à (re)découvrir
2015
Référence : 201511123537; National audience; Le principal challenge de l’industrie des biotechnologies est lié au développement d’un procédé qui est à la fois économique et efficace en utilisant des matières premières renouvelables pour délivrer des produits à haute valeur ajoutée. La fermentation en milieu solide (FMS) qui met en œuvre des microorganismes sur des matières premières biologiques est un procédé pouvant répondre à ces problématiques.
Escherichia coli cytolethal distending toxin blocks the HeLa cell cycle at the G2/M transition by preventing cdc2 protein kinase dephosphorylation an…
1997
Cytolethal distending toxins (CDT) constitute an emerging heterogeneous family of bacterial toxins whose common biological property is to inhibit the proliferation of cells in culture by blocking their cycle at G2/M phase. In this study, we investigated the molecular mechanisms underlying the block caused by CDT from Escherichia coli on synchronized HeLa cell cultures. To this end, we studied specifically the behavior of the two subunits of the complex that determines entry into mitosis, i.e., cyclin B1, the regulatory unit, and cdc2 protein kinase, the catalytic unit. We thus demonstrate that CDT causes cell accumulation in G2 and not in M, that it does not slow the progression of cells th…
Production of halogenated compounds by Bjerkandera adusta.
1994
International audience; The white-rot fungusBjerkandera adusta produces volatile chlorinated phenyl compounds. The main compounds identified were 3-chloro-4-methoxybenzaldehyde (3-chloro-p-anisaldehyde), 3-chloro-4-methoxybenzyl alcohol (3-chloro-p-anisyl alcohol), 3,5-dichloro-4-methoxybenzaldehyde (3,5-dichloro-p-anisaldehyde), and 3,5-dichloro, 4-methoxybenzyl alcohol (3,5-dichloro-p-anisyl alcohol).p-Anisaldehyde, veratraldehyde and the corresponding alcohols,p-anisyl alcohol and veratryl alcohol were produced simultaneously. Even with a very low concentration of chloride in the medium (<>–5 m), chlorinated aromatic compounds were still observed. Addition of bromide to the culture mediu…
Clinicopathological profile of gastrointestinal tuberculosis: a multinational ID-IRI study
2020
Data are relatively scarce on gastro-intestinal tuberculosis (GITB). Most studies are old and from single centers, or did not include immunosuppressed patients. Thus, we aimed to determine the clinical, radiological, and laboratory profiles of GITB. We included adults with proven GITB treated between 2000 and 2018. Patients were enrolled from 21 referral centers in 8 countries (Belgium, Egypt, France, Italy, Kazakhstan, Saudi Arabia, UK, and Turkey). One hundred four patients were included. Terminal ileum (n = 46, 44.2%), small intestines except terminal ileum (n = 36, 34.6%), colon (n = 29, 27.8%), stomach (n = 6, 5.7%), and perianal (one patient) were the sites of GITB. One-third of all p…
Portraying infective endocarditis
2019
Infective endocarditis is a growing problem with many shifts due to ever-increasing comorbid illnesses, invasive procedures, and increase in the elderly. We performed this multinational study to depict definite infective endocarditis. Adult patients with definite endocarditis hospitalized between January 1, 2015, and October 1, 2018, were included from 41 hospitals in 13 countries. We included microbiological features, types and severity of the disease, complications, but excluded therapeutic parameters. A total of 867 patients were included. A total of 631 (72.8%) patients had native valve endocarditis (NVE), 214 (24.7%) patients had prosthetic valve endocarditis (PVE), 21 (2.4%) patients …
Truncated internalin A and asymptomatic Listeria monocytogenes carriage: in vivo investigation by allelic exchange
2004
ABSTRACT Allelic exchange of the region coding for the C terminus of InlA between one epidemic (with an 80-kDa InlA) and one asymptomatic (with a 47-kDa InlA) carriage Listeria monocytogenes strain confirmed the need for this region for internalin entry in vitro. Interestingly, restoration of internalin A functionality did not result in full virulence in chicken embryo assays.
Identification of the Weevil immune genes and their expression in the bacteriome tissue
2008
Abstract Background Persistent infections with mutualistic intracellular bacteria (endosymbionts) are well represented in insects and are considered to be a driving force in evolution. However, while pathogenic relationships have been well studied over the last decades very little is known about the recognition of the endosymbionts by the host immune system and the mechanism that limits their infection to the bacteria-bearing host tissue (the bacteriome). Results To study bacteriome immune specificity, we first identified immune-relevant genes of the weevil Sitophilus zeamais by using suppressive subtractive hybridization (SSH) and then analyzed their full-length coding sequences obtained b…
Modeling the effect of ethanol vapor on the germination time of Penicillium chrysogenum.
2005
The influence of ethanol vapor on germination of Penicillium chrysogenum was determined on yeast nitrogen base plus glucose agar medium at 25 degrees C. Ethanol vapors were generated by 0 to 6% (wt/wt) ethanol solutions at the bottom of hermetically closed petri dishes. The logistic equation was used to describe the data as the percentage of germination versus time and to estimate the germination time. The effect of ethanol concentration on germination time was described by a new reparameterized equation, resulting in an estimated limiting ethanol concentration of 4.3%. Up to 3% ethanol, all spores germinated, and the germination time increased with increasing ethanol concentration. At 3.5 …
Genomics based approach to identify the genes involved in ipu mineralization in sphingomonas sp.sh
2010
Phenylurea herbicide isoproturon, 3-(4-isopropylphenyl)-1,1-dimethylurea (IPU), was found to be rapidly mineralised in aFrench agricultural soil previously exposed to IPU. A bacterial strain able to metabolise IPU was isolated from this soil adapted toIPU mineralization.
Isoproturon
2010
Frequent use of phenylurea herbicide isoproturon (IPU) in agricultural fields has resulted not only in the contamination of the natural resources including soil and water but also in the adaptation of the soil microflora to its rapid degradation. However, up to now, the mechanisms underlying this microbial adaptation are not well elucidated. The aim of this study was to explore the processes and factors implicated in IPU degradation from the agricultural field to the genes coding for catabolic genes. The study carried out at the experimental field of Epoisses cropped with a winter wheat / barley / rape seed crop rotation indicated that as a result of its periodically repeated use, the soil …