Methylibium subsaxonicum spec. nov., a Betaproteobacterium Isolated from a Hardwater Rivulet

Aquariibacter albus gen. nov., sp. nov., a new member of the order Burkholderiales, isolated from a freshwater aquarium

A novel bacterium, strain SJAQ100^T, was isolated from a freshwater aquarium and was characterized taxonomically and phylogenetically. Strain SJAQ100^T was a Gram-stain-negative, aerobic, rod-shaped and non-motile bacterium. The strain grew optimally with 0 % NaCl and at 25-37 °C on Reasoner's 2A agar. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the strain SJAQ100^T clustered with members of Burkholderiales incertae sedis in the order Burkholderiales, but sequence similarities to known species were less than 96.5 %. The genomic DNA G+C content of strain SJAQ100^T was 71.2 mol%. Genomic comparisons of strain SJAQ100^T with species in the order Burkholderiales were made using the Genome-to-Genome Distance Calculator, average nucleotide identity and average amino acid identity analyses (values indicated ≤22.1, ≤78.1, and ≤68.1 % respectively). Strain SJAQ100^T contained C_16 : 0 and C_16 : 1  ω7c/C_16 : 1  ω6c as major fatty acids and Q-8 as the major quinone. The major polyamines were putrescine and cadaverine. Strain SJAQ100^T contained phosphatidylethanolamine and diphosphatidylglycerol as major polar lipids. Based on the genotypic, chemotaxonomic and phenotypic results, strain SJAQ100^T represents a novel genus and species, Aquariibacter albus gen. nov., sp. nov., which belongs to order Burkholderiales and the class Betaproteobacteria. The type strain is SJAQ100^T (=KCTC 72203^T=CGMCC 1.18869^T=MCC 4385^T).

Dissection of the genus Methylibium: reclassification of Methylibium fulvum as Rhizobacter fulvus comb. nov., Methylibium aquaticum as Piscinibacter aquaticus gen. nov., comb. nov. and Methylibium subsaxonicum as Rivibacter subsaxonicus gen. nov., comb. nov. and emended descriptions of the genera Rhizobacter and Methylibium

16S rRNA gene sequenced-based phylogeny indicates that Rhizobacter dauci ATCC 43778(T) branches within the radiation of Methylibium type strains. A comparative chemotaxonomic study including fatty acid methyl esters, polar lipids and polyamines reveals significant differences that, in combination with the topology of phylogenetic trees, support a dissection of the genus Methylibium. The proposals of this study include the transfer of Methylibium fulvum to the genus Rhizobacter as Rhizobacter fulvus comb. nov. (type strain Gsoil 322(T) =KCTC 12591(T) =DSM 19916(T)) and the reclassification of Methylibium aquaticum as Piscinibacter aquaticus gen. nov., comb. nov. (the type strain of Piscinibacter aquaticus is IMCC1728(T) =KCCM 42364(T) =NBRC 102349(T) =DSM 19915(T)) and of Methylibium subsaxonicum as Rivibacter subsaxonicus gen. nov., comb. nov. (the type strain of Rivibacter subsaxonicus is BF49(T) =DSM 19570(T) =CIP 109700(T)). As a consequence of these reclassifications, emended descriptions of the genera Methylibium and Rhizobacter are provided.

List of new names and new combinations previously effectively, but not validly, published

The purpose of this announcement is to effect the valid publication of the following effectively published new names and new combinations under the procedure described in the Bacteriological Code (1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should send three copies of the pertinent reprint or photocopies thereof, or an electronic copy of the published paper, to the IJSEM Editorial Office for confirmation that all of the other requirements for valid publication have been met. It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries (i.e. documents certifying deposition and availability of type strains). It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below, and these authors' names will be included in the author index of the present issue and in the volume author index. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in bacteriological nomenclature. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.