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Culture Collection Strains (culture + collection_strain)
Selected AbstractsDNA BARCODING OF CHLORARACHNIOPHYTES USING NUCLEOMORPH ITS SEQUENCES,JOURNAL OF PHYCOLOGY, Issue 4 2010Gillian H. Gile Chlorarachniophytes are a small group of marine photosynthetic protists. They are best known as examples of an intermediate stage of secondary endosymbiosis: their plastids are derived from green algae and retain a highly reduced nucleus, called a nucleomorph, between the inner and outer pairs of membranes. Chlorarachniophytes can be challenging to identify to the species level, due to their small size, complex life cycles, and the fact that even genus-level diagnostic morphological characters are observable only by EM. Few species have been formally described, and many available culture collection strains remain unnamed. To alleviate this difficulty, we have developed a barcoding system for rapid and accurate identification of chlorarachniophyte species in culture, based on the internal transcribed spacer (ITS) region of the nucleomorph rRNA cistron. Although this is a multicopy locus, encoded in both subtelomeric regions of each chromosome, interlocus variability is low due to gene conversion by homologous recombination in this region. Here, we present barcode sequences for 39 cultured strains of chlorarachniophytes (>80% of currently available strains). Based on barcode data, other published molecular data, and information from culture records, we were able to recommend names for 21 out of the 24 unidentified, partially identified, or misidentified chlorarachniophyte strains in culture. Most strains could be assigned to previously described species, but at least two to as many as five new species may be present among cultured strains. [source] Conditions for conjugative transposon transfer in Lactococcus lactisLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2000G. Blaiotta Three different techniques for bacterial mating were applied to wild type and culture collection strains of Lactococcus lactis harbouring transposons: direct plate conjugation, filter mating and mating on milk agar. Efficiencies and frequencies of transfer were compared. Transconjugants were characterized by marker properties and molecular assays. Transposon-coded Suc+ Nis+ phenotype as well as Suc+ Bac+ Nis, phenotype were transferred with frequencies ranging between 10,9 and 10,6. Milk agar plate mating was the best technique for obtaining gene transfer events involving wild type lactococci. [source] Phenotypic and genotypic characterization of reference strains of the genus AspergillusMYCOSES, Issue 3-4 2001P.-M. Rath Aspergillus; Genotypisierung; Biotypisierung; SDS-PAGE; RAPD Summary. Twenty-five culture collection strains from four Aspergillus species (A. fumigatus n = 8, A. flavus n = 8, A. niger n= 4, A. nidulans n = 5) were characterized by four methods: (i) determination of patterns in an assimilation assay; (ii) protein pattern of whole mycelial cell lysates in the sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE); (iii) reactivity of a pool serum obtained from cystic fibrosis patients with mycelial lysates in the immunoblot; and (iv) random amplification of polymorphic DNA (RAPD) with eight primers having arbitrary or repetitive sequences. In the assimilation assay the A. fumigatus strains showed identical patterns in contrast to the strains of the species A. flavus, A. niger, and A. nidulans, which each showed four patterns. In the SDS-PAGE no differences in the band patterns in the A. fumigatus strains were found, in contrast to the A. flavus (three patterns), A. nidulans (five patterns) and A. niger strains (two patterns). The immunoblot patterns were characteristic for each species with bands at 62 and 17/18 kDa in the A. fumigatus strains, at 51 and 18 kDa in the A. flavus strains, at 51 kDa in the A. niger strains, and at 51, 40 and 17/18 kDa in the A. nidulans strains allowing, however, no intraspecies typing. In the RAPD assay four out of eight primers gave interpretable patterns with 3,20 bands. None of the primers showed sufficient discriminatory power when used alone. However, when combining the results of two of the primers (5,-GTA TTG CCC T-3, and 5,-GAT AGA TAG ATA GAT A-3,) all strains except two A. fumigatus strains could be clearly separated from each other. It is concluded that the the RAPD assay showed the most discriminatory power in all Aspergillus species investigated. In contrast to the phenotypically similar A. fumigatus strains, the strains of the species A. flavus, A. nidulans and A. niger differed in their phenotypic characteristics. The presented data of strains from international culture collections may serve as basis for interlaboratory standardization of typing methods. Zusammenfassung. Fünfundzwanzig Aspergillus -Stämme aus internationalen Stammsammlungen (A. fumigatus n = 8, A. flavus n = 8, A. niger n = 4, A. nidulans n = 5) wurden mit vier Methoden charakterisiert: (1) Reaktionsmuster in einem Assimilationstest (2) Proteinmuster von Ganzzell-Lysaten in der SDS-PAGE (3) Reaktionsmuster eines Poolserums von Patienten mit Mukoviszidose mit Zellextrakten im Immunoblot und (4) random amplification of polymorphic DNA (RAPD) mit acht Primern zufälliger oder repetitiver Sequenz. Im Assimilationstest zeigten die A. fumigatus -Stämme identische Muster, während die Stämme der Spezies A.flavus, A. niger und A. nidulans je vier Reaktionsmuster aufwiesen. In der SDS-PAGE wiesen die A. fumigatus -Stämme identische Muster auf, während die A. flavus -Stämme drei, die A. niger -Stämme zwei, und die A. nidulans -Stämme fünf verschiedene Muster zeigten. Im Immunoblot waren die Muster für jede Spezies charakteristisch mit Banden bei 62 kDa und 17/18 kDa bei A. fumigatus, bei 51 kDa und 18 kDa bei A. flavus, bei 51 kDa bei A. niger und bei 51, 40 und 17/18 kDa bei A. nidulans. Eine Intraspezies-Typisierung gelang jedoch nicht. In der RAPD ergaben vier der acht Primer interpretierbare Muster mit 3 bis 20 Banden. Keiner der Primer alleine zeigte eine ausreichende Diskriminationskapazität. Wurden die Resultate von zwei Primern (5,-GTA TTG CCC T-3, and 5,-GAT AGA TAG ATA GAT A-3,) kombiniert, konnten mit Ausnahme von zwei A. fumigatus -Stämmen alle Isolate voneinander abgegrenzt werden. Die Ergebnisse zeigen, daß die RAPD die größte Diskriminationskapazität aufweist. Im Gegensatz zu den phänotypisch ähnlichen A. fumigatus -Stämmen unterschieden sich die Stämme der Spezies A. flavus, A. nidulans und A. niger voneinander. Die gezeigten Daten von Stämmen internationaler Stammsammlungen können als Grundlage für die Standardisierung von Typisierungsmethoden dienen. [source] Identification of medically important Aspergillus species by single strand conformational polymorphism (SSCP) of the PCR-amplified intergenic spacer region Identifizierung humanmedizinisch relevanter Aspergillus-Arten durch Analyse der Einzelstrang-Konformations-Polymorphismen der amplifizierten Intergenic-Spacer-RegionMYCOSES, Issue 11-12 2000P.-M. Rath Aspergillus; Identifizierung; ITS-Region; PCR; SSCP Summary., The amplified 5.8S RNA coding DNA with the neighbouring internal transcribed spacers ITS I and ITS II (ITS I,5.8S rDNA , ITS II) of 27 culture collection strains of Aspergillus fumigatus, Aspergillus flavus, Aspergillus nidulans, Aspergillus niger, and Aspergillus terreus were investigated by single strand conformational polymorphism (SSCP) analysis. All strains showed a polymerase gel electrophoresis (PCR) product of 0.6 kb. Separation of DNA single strands of the PCR product in an acrylamide-bisacrylamide gel containing formamide SSCP resulted in individual patterns for each of the species. A minor variability within the species A. fumigatus and A. flavus did not affect the correct species identification. The results were confirmed when investigating 55 wild strains from patients and the environment. It is concluded that the analysis of the amplified ITS I,5.8S rDNA , ITS II region by SSCP allows the differentiation of the medically most relevant aspergilli. As the method does not require morphologically fully developed fungal colonies, it yields species diagnosis faster than the conventional macroscopic and microscopic identification. Zusammenfassung., Die amplifizierte 5,8S RNA kodierende DNA mit den benachbarten Internal Transcribed Spacern ITS I und ITS II (ITS I,5,8S rDNA , ITS II) von 27 Referenzstämmen der Spezies Aspergillus fumigatus, A. flavus, A. nidulans, A. niger und A. terreus wurde durch Analyse der Einzelstrang-Konformations-Polymorphismen (SSCP) untersucht. Alle Stämme zeigten ein PCR-Produkt mit einer Größe von 0,6 kb. Die SSCP-Muster nach Auftrennung der DNA-Einzelstränge dieses Produktes in einem Acrylamid-Bisacrylamid Gel mit Formamid waren für jede der untersuchten Spezies charakteristisch. Eine geringfügige Variabilität der Muster bei den Spezies A. fumigatus und A. flavus schränkte die Interpretation nicht ein. Die Ergebnisse wurden bei der Analyse von 55 Isolaten von Patienten und aus der Umwelt bestätigt. Die SSCP-Analyse der amplifizierten ITS I,5,8S rDNA , ITS II Region erlaubt somit eine Differenzierung der humanmedizinisch wichtigsten Aspergillus -Spezies vor der Ausbildung charakteristischer makro- und mikromorphologischer Strukturen. [source] In-vitro evaluation of the adhesion to polypropylene sutures of non-pigmented, rapidly growing mycobacteriaCLINICAL MICROBIOLOGY AND INFECTION, Issue 9 2007N. Zamora Abstract The ability of non-pigmented, rapidly growing mycobacteria (NPRGM) to attach to polypropylene sutures was evaluated using an in-vitro assay. Thirty clinical isolates and five culture collection strains of NPRGM, together with Staphylococcus epidermidis ATCC 35983, were tested. Mycobacterium fortuitum and Mycobacterium chelonae showed the highest attachment ability, which differed significantly from the results obtained with Mycobacterium peregrinum. According to these results, NPRGM are able to attach to polypropylene sutures, and the species implicated most frequently in human infection showed increased levels of attachment in comparison with the other mycobacteria studied. [source] | |||||||||||||