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The anaerobic glycerol pathway was studied in seven enterobacterial species selected as representative of different behaviours in terms of anaerobic glycerol dissimilation. The presence of oxidative and reductive pathways of the dha regulon in Klebsiella pneumoniae enabled the cells to grow fermentatively on glycerol. The first two enzymes of the dha regulon (glycerol dehydrogenase type I and dihydroxyacetone kinase) represent the oxidative branch, while the latter two (glycerol dehydratase and 1,3-propanediol dehydrogenase) represent the reductive branch of glycerol fermentation. The slower utilization of glycerol by K. oxytoca was attributed to low production of 1,3-propanediol. K. oxytoca lacked glycerol dehydratase and demonstrated low 1,3-propanediol dehydrogenase activity. K. planticola and K. ozaenae differed from K. pneumoniae and K. oxytoca in lacking the ability to grow on glycerol. K. planticola lacked both enzymes of the reductive branch of glycerol fermentation, and K. ozaenae possessed glycerol dehydrogenase only. K. rhinoscleromatis and Hafnia alvei, like Escherichia coli, did not possess a dha regulon. The glycerol dehydrogenase type II of H. alvei was distinct from that of E. coli. The phenotypic diversity of anaerobic glycerol dissimilation may have taxonomic applications.

Summary It is admitted that one of the characteristics of pseudomonads is their inability to accumulate poly(3-hydroxybutyrate). In this paper, we show that poly(3-hydroxyoctanoate) synthesis is restricted to Pseudomonas rRNA homology group I, which includes both fluorescent and nonfluorescent species. However, within the genus Pseudomonas, the P. aeruginosa complex can be subdivided into two groups : the “P. aeruginosa group”, which includes P. aeruginosa, P. alcaligenes, P. citronellolis, P. mendocina, produce poly(3-hydroxyoctanoate) from octanoate and the “P. oleovorans group” which includes the type strain of P. oleovorans, P. pseudoalcaligenes and two Pseudomonas sp., produce poly(3-hydroxybutyrate) during cultivation on octanoate. Strain GPo1 (ATCC 29347) formely identified as P. oleovorans and known to produce various mediumside-chain PHAs such as poly(3-hydroxyoctanoate) has been reclassified in the P. putida complex.

DNA chip technology has greatly evolved over the last decade and, associated with complete genome sequencing, is in the process of introducing a revolution into biological research. It is providing new and unique tools for studying emerging diseases outbreaks and epidemics. Nevertheless, microbiological surveillance, medical diagnosis, and field work involve a number of difficulties for which these new techniques have not yet been validated. Currently available chips are still limited in their application, but offer a powerful and economical alternative to former methods and will undoubtedly offer a range of unexplored applications in coming years.

As part of the European Copernicus programme, the Sentinel-1 mission, based on a constellation of two SAR satellites, ensures continuity for Europe of C-band SAR observations. Sentinel-1A and Sentinel-1B were respectively launched from Kourou on 3rd April 2014 and 25th April 2016. Full Operations Capacity (FOC) of the mission is expected to be achieved following the completion of the operational qualification of the Sentinel-1 constellation (Sentinel-1A and Sentinel-1B), early 2017 indicatively. The presentation will give an overview of the overall mission status and will focus on the Sentinel-1A routine operations activities and the start of the Sentinel-1B operations. Topics including mission achievements, mission observation scenario of the constellation, ground segment operations performance, throughput and data access will be presented.

The reassociation properties of DNA provide invaluable taxonomic tools. Different methods may give different reassociation values. However, the thermal stability of reassociated DNA strands (a measurement that seems independent of method) is useful in delineating genomic species. Although many phenotypically defined species have been confirmed by DNA reassociation, some medically important genomic species previously had been split into several nomenspecies on the basis of a few characteristics whereas some environmental genomic species had been lumped into unidentifiable aggregates. It might take some time before the nomenclature can be adapted to new taxonomic findings.

Recent work describing six named species and two unnamed genomospecies within Citrobacter has enlarged the genus to 11 species. DNA relatedness and phenotypic tests were used to determine how well these species can be identified. One hundred thirty-six strains were identified to species level by DNA relatedness and then identified phenotypically in a blinded fashion. By using conventional tests, 119 of the 136 strains (88%) were correctly identified to species level. Three additional strains (2%) were identified as citrobacteria but were not identified to species level, and 14 strains (10%) were misidentified as other Citrobacter species. Carbon source utilization tests were used to identify 86 of the strains. Eighty-four strains (98%) were correctly identified, and two strains (2%) were misidentified as other Citrobacter species. Additional strains of Citrobacter genomospecies 10 and Citrobacter genomospecies 11 were identified, allowing these species to be formally named as Citrobacter gillenii sp. nov. and Citrobacter murliniae sp. nov., respectively.

We screened the La Plata drinking water distribution network for fecal and total coliform bacterial indicator by purification procedures, cultivating 66 membrane-filtered samples from the two networks on m-T7 agar. Subterranean and river-derived water yielded 13 and 18 confirmed gram-negative bacillus isolates, with 54% and 72% representing total coliforms, respectively. Those from the former source were Klebsiella oxytoca, Enterobacter agglomerans, and Enterobacter aerogenes and from the latter Klebsiella oxytoca, Enterobacter agglomerans, and Enterobacter cloacae, genomic group 3. Since 58% of the samples were positive using m-T7 medium it is suggested that the inclusion in standard quality control protocols should be implemented.

International audience; Cell-wall-deficient forms from nine rapidly growing mycobacteria were prepared by treating the cells during exponential growth with D-cycloserine, glycine, lysozyme, EDTA, and lithium chloride for the time corresponding to three cell divisions. The cell-wall-deficient forms were then converted to spheroplasts in the presence of lysozyme and EDTA. The spheroplasts were characterized by their susceptibility to lysis by 0.5% (wt/vol) sodium dodecyl sulfate (SDS), as well as by their response to eight biochemical tests commonly used for mycobacterial identification. Intact cells, on the other hand, could not be lysed even with 2.5% (wt/vol) SDS and, moreover, gave negative responses to certain biochemical tests that turned positive once the cell wall was removed. This implied an exclusion mechanism at the level of the mycobacterial wall. The present method of spheroplast formation was found applicable to various mycobacterial species.