8 resultados para Leptodactylus ajurauna sp nov.
em Université de Lausanne, Switzerland
Resumo:
A Gram-negative, rod-shaped, aerobic bacterium, designated strain RP007(T), was isolated from a polycyclic aromatic hydrocarbon-contaminated soil in New Zealand. Two additional strains were recovered from a compost heap in Belgium (LMG 18808) and from the rhizosphere of maize in the Netherlands (LMG 24204). The three strains had virtually identical 16S rRNA gene sequences and whole-cell protein profiles, and they were identified as members of the genus Burkholderia, with Burkholderia phenazinium as their closest relative. Strain RP007(T) had a DNA G+C content of 63.5 mol% and could be distinguished from B. phenazinium based on a range of biochemical characteristics. Strain RP007(T) showed levels of DNA-DNA relatedness towards the type strain of B. phenazinium and those of other recognized Burkholderia species of less than 30 %. The results of 16S rRNA gene sequence analysis, DNA-DNA hybridization experiments and physiological and biochemical tests allowed the differentiation of strain RP007(T) from all recognized species of the genus Burkholderia. Strains RP007(T), LMG 18808 and LMG 24204 are therefore considered to represent a single novel species of the genus Burkholderia, for which the name Burkholderia sartisoli sp. nov. is proposed. The type strain is RP007(T) (=LMG 24000(T) =CCUG 53604(T) =ICMP 13529(T)).
Resumo:
From a collection of yeast isolates isolated from patients in Tunisian hospitals between September 2006 and July 2010, the yeast strain JEY63 (CBS 12513), isolated from a 50-year-old male that suffered from oral thrush, could not be identified to the species level using conventional methods used in clinical laboratories. These methods include matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), germ tube formation, and the use of CHROMagar Candida and metabolic galleries. Sequence analysis of the nuclear rRNA (18S rRNA, 5.8S rRNA, and 26S rRNA) and internal transcribed spacer regions (ITS1 and ITS2) indicated that the ribosomal DNA sequences of this species were not yet reported. Multiple gene phylogenic analyses suggested that this isolate clustered at the base of the Dipodascaceae (Saccharomycetales, Saccharomycetes, and Ascomycota). JEY63 was named Candida tunisiensis sp. nov. according to several phenotypic criteria and its geographical origin. C. tunisiensis was able to grow at 42°C and does not form chlamydospores and hyphae but could grow as yeast and pseudohyphal forms. C. tunisiensis exhibited most probably a haploid genome with an estimated size of 10 Mb on at least three chromosomes. Using European Committee for Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) Candida albicans susceptibility breakpoints as a reference, C. tunisiensis was resistant to fluconazole (MIC = 8 μg/ml), voriconazole (MIC = 0.5 μg/ml), itraconazole (MIC = 16 μg/ml), and amphotericin B (MIC = 4 μg/ml) but still susceptible to posaconazole (MIC = 0.008 μg/ml) and caspofungin (MIC = 0.5 μg/ml). In conclusion, MALDI-TOF MS permitted the early selection of an unusual isolate, which was still unreported in molecular databases but could not be unambiguously classified based on phylogenetic approaches.
Resumo:
An amoeba isolated from an aquatic biotope, identified morphologically as Saccamoeba limax, was found harbouring mutualistic rod-shaped gram-negative bacteria. During their cultivation on agar plates, a coinfection also by lysis-inducing chlamydia-like organisms was found in some subpopulations of that amoeba. .Here we provide a molecular-based identification of both the amoeba host and the two bacterial endosymbionts. Analysis of the 18S rRNA gene revealed that this strain is the sister-group to Glaeseria, for which we proposed the name Saccamoeba lacustris. The rod-shaped endosymbiont was identified as a member of Variovorax paradoxus group (Comamonadaceae, Beta-Proteobacteria). No growth on bacteriological agars was recorded, hence this symbiont might be strictly intracellular. The chlamydia-like parasite was unable to infect Acanthamoeba and other amoebae in coculture, showing high host specificity. Phylogenetic analysis based on the 16S rDNA indicated that it is a new member of the family Parachlamydiaceae (order Chlamydiales), for which we proposed the name 'Candidatus Metachlamydia lacustris'.
Resumo:
Here, we report the culture and characterization of an alphaproteobacterium of the order Rhizobiales, isolated from the gut of the honey bee Apis mellifera. Strain PEB0122T shares >95 % 16S rRNA gene sequence similarity with species of the genus Bartonella, a group of mammalian pathogens transmitted by bloodsucking arthropods. Phylogenetic analyses showed that PEB0122T and related strains from the honey bee gut form a sister clade of the genus Bartonella. Optimal growth of strain PEB0122T was obtained on solid media supplemented with defibrinated sheep blood under microaerophilic conditions at 35-37 °C, which is consistent with the cultural characteristics of other species of the genus Bartonella. Reduced growth of strain PEB0122T also occurred under aerobic conditions. The rod-shaped cells of strain PEB0122T had a mean length of 1.2-1.8 μm and revealed hairy surface structures. Strain PEB0122T was positive for catalase, cytochrome c oxidase, urease and nitrate reductase. The fatty acid composition was comparable to those of other species of the genus Bartonella, with palmitic acid (C16 : 0) and isomers of 18- and 19-carbon chains being the most abundant. The genomic DNA G+C content of PEB0122T was determined to be about 45.5 mol%. The high 16S rRNA gene sequence similarity with species of Bartonella and its close phylogenetic position suggest that strain PEB0122T represents a novel species within the genus Bartonella, for which we propose the name Bartonella apis sp. nov. The type strain is PEB0122T ( = NCIMB 14961T = DSM 29779T).
Resumo:
Using ameba coculture, we grew a Naegleria endosymbiont. Phenotypic, genetic, and phylogenetic analyses supported its affiliation as Protochlamydia naegleriophila sp. nov. We then developed a specific diagnostic PCR for Protochlamydia spp. When applied to bronchoalveolar lavages, results of this PCR were positive for 1 patient with pneumonia. Further studies are needed to assess the role of Protochlamydia spp. in pneumonia.
Resumo:
A new genus (Triassiphaeodina gen. nov.) and two new species (Medusetta japonica sp. nov. and Triassiphaeodina niyodoensis sp. nov.) of Late Triassic (Rhaetian) phaeodarian Radiolaria are described from a phosphatic nodule found in melange rocks of the Northern Chichibu Belt, Shikoku, Japan. The Rhaetian age of the nodule and of the phaeodarian new taxa is based on co-occurring Polycystina Radiolaria, including Bipedis acrostylus Bragin, Livarella densiporata Kozur and Mostler, Fontinella primitiva Carter, and Ferresium sp. A of Carter (1993). This finding shows that phaeodarian Radiolaria were already represented in Late Triassic oceans, with morphologies similar to those known in the Late Cretaceous and Cenozoic, from which they have previously been reported. The new taxa described herein represent the oldest known phaeodarian fossils.
Resumo:
Conventional methods are sometimes insufficient to identify human bacterial pathogens, and alternative techniques, often molecular, are required. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) identified with a valid score 45.9% of 410 clinical isolates from 207 different difficult-to-identify species having required 16S rRNA gene sequencing. MALDI-TOF MS might represent an alternative to 16S rRNA gene sequencing.
Resumo:
The karyotype, morphology and biology of Crocidura from Fuerteventura (Canary Islands) are described. The species has a diploid chromosome number of 2n = 36, thus differing from all other species of the genus. A detailed morphological comparison of the shrews from Fuerteventura, Lanzarote and other islets with C. russula from Morocco revealed specific characters for both taxa. Differences were also observed in biological parameters. It is concluded that the Canary Island populations of Crocidura form a biological species which is consequently named Crocidura canariensis sp. nov.