10 research outputs found
Safety assessment of dairy microorganisms: Geotrichum candidumâ
International audienc
Genetic diversity among Geotrichum candidum strains from various substrates studied using RAM and RAPD-PCR.
International audienceAssessment of genetic diversity within the species Geotrichum candidum and development of tools to trace the strains that play an important role in the agro food industry
Relationships between Exposure to Bioaerosols, Moldy Surface and Symptoms in French Mold- Damaged Homes
International audienc
Interest of the qPCR method calibrated with flow cytometry to quantify Aspergillus versicolor in mold-damaged homes and comparison with the cultural approach
International audienc
Development of primers for detecting dominant yeasts in smear-ripened cheeses
International audiencePCR primers were developed for the specific detection of Clavispora lusitaniae, Debaryomyces hansenii var hansenii, Geotrichum candidum, Kluyveromyces lactis and K. marxianus and Yarrowia lipolytica, yeast species commonly found on the surface of smear cheese. Forty eight representative strains frequently found in smear cheeses or taxonomically related to the target yeasts were used as templates, to validate the designed primers. The specific and selective detection of these yeasts was effective in situ, in Livarot smear, without yeast isolation and culture and was comparable with data obtained with a conventional method. The primers described here have thus potential for PCR studies applied to cheese. It should also be possible to use some of these primers with other substrates
Intra-species chromosome-length polymorphism in Geotrichum candidum revealed by pulsed field gel electrophoresis.
International audienceGeotrichum candidum is an ascomycetous anamorph yeast-like fungus found in various habitats. It is a component of the natural flora of milk and is used as a maturing agent for both soft and hard cheeses. This microorganism displays phenotypic variability and may act as an opportunist pathogen, causing geotrichosis. Cytological analysis of G. candidum strain ATCC 204307 showed this strain to have eight chromosomes. We prepared chromosomal DNA from 13 strains of G. candidum differing in habitat and morphotype. We used pulsed field gel electrophoresis (PFGE) in two sets of conditions to determine the size of the chromosomal DNA molecules. The strains investigated had five to eight chromosomes, 0.6 to 4.5 Mb in size. We estimated genome size in these 13 strains to be between 11 and 19 Mb. Pulsed-field gel electrophoresis profiles showed a high degree of polymorphism, indicating considerable variability between strains. Genome size and the presence of large chromosomes appeared to be correlated with morphotype. Strains with a mold-like or intermediate morphotype tended to have larger genomes than strains with a yeast-like morphotype did
Suivi de la qualitĂ© de lâair dans un centre de lutte contre le cancer : Ă©valuation et caractĂ©risation de lâexposition aux contaminants fongiques (Biohospitalair)
National audienceContexte. La qualitĂ© de lâair dans un Ă©tablissement de soins est une prĂ©occupation importante en termes de santĂ© publique, en particulier chez les patients immunodĂ©primĂ©s qui peuvent ĂȘtre exposĂ©s Ă des contaminants dâorigine microbiologique tels que les moisissures, les endotoxines, les (1,3)-Ă-D-glucanes et les mycotoxines. MĂ©thodes. Le projet Biohospitalair, soutenu par lâAdeme (Agence de lâenvironnement et de la maĂźtrise de lâĂ©nergie), a consistĂ©, durant deux ans, Ă prĂ©lever mensuellement et Ă caractĂ©riser des bioaĂ©rosols et des isolats fongiques collectĂ©s dans un centre de lutte contre le cancer (centre F. Baclesse), dans des zones ne possĂ©dant pas de traitement dâair spĂ©cifique. RĂ©sultats. Parmi plus de cent espĂšces fongiques diffĂ©rentes identifiĂ©es, certaines peuvent ĂȘtre retenues en raison de leur frĂ©quence, de leur concentration et/ou de leur capacitĂ© Ă produire in vitro des mycotoxines : Aspergillus fumigatus, Aspergillus melleus, Aspergillus niger, Aspergillus versicolor, Cladosporium herbarum, Paecilomyces lilacinus, Penicillium brevicompactum. Dâun point de vue quantitatif, les niveaux moyens en particules fongiques viables restent infĂ©rieurs Ă 30 CFU/m3 dâair et sont corrĂ©lĂ©s au nombre de particules totales de 0,30 Ă 20 ”m. Cette Ă©tude met Ă©galement en Ă©vidence des variations saisonniĂšres avec lâapparition de pics de particules fongiques en Ă©tĂ© et en automne. De plus, lâanalyse statistique rĂ©vĂšle que lâhumiditĂ© relative est une variable explicative du nombre de CFU/m3 dâair, ce qui pourrait faire de ce paramĂštre un indicateur de contamination fongique pertinent