Amnimonas aquatica gen. nov., sp. nov., Isolated from a Freshwater River.

A gram-stain-negative and strictly aerobic bacterium, designated strain HR-ET, was isolated from a water sample of the Han River in South Korea. Cells were catalase-negative and oxidase-positive motile rods with a flagellum. The strain grew at 10-37 °C and pH 7-8 and in the presence of 0-2% (w/v) NaCl. Ubiquinone-8 and summed features 3 (comprising C16:1ω7c and/or C16:1ω6c) and 8 (comprising C18:1ω7c and/or C18:1ω6c), C16:0, iso-C10:0 and C12:0 3-OH were identified as the major respiratory quinone and fatty acids (>5%), respectively. The 16S rRNA gene sequence of strain HR-ET shared the highest similarities with Perlucidibaca piscinae IMCC 1704T (98.1%), Perlucidibaca aquatica BK296T (96.8%), Paraperlucidibaca baekdonensis RL-2T (95.8%) and Paraperlucidibaca wandonensis WT-RY4T (95.7%). However, strain HR-ET formed a phylogenetic lineage distinct from members of the family Moraxellaceae, and a taxonomic analysis by RDP Naïve Bayesian rRNA Classifier classified strain HR-ET as a new genus of the family Moraxellaceae. In addition, analyses based on rpoD, secA and gyrB gene sequences also showed that strain HR-ET formed a lineage distinct from those of the genera Perlucidibaca and Paraperlucidibaca. Average nucleotide identity and in silico DNA-DNA hybridization values between strain HR-ET and the type strains of P. piscinae and P. aquatica were very low with 80.1 and 23.6% and 75.7 and 21.2%, respectively. The DNA G+C content was 67.0 mol%. Based on the phenotypic, genotypic and chemotaxonomic analyses, strain HR-ET represents a novel genus of the family Moraxellaceae, for which the name Amnimonas aquatica gen. nov., sp. nov. is proposed. The type strain of the type species is HR-ET (=KACC 19408T=JCM 32266T).

Paraperlucidibaca baekdonensis gen. nov., sp. nov., isolated from seawater.

A Gram-negative, non-spore-forming, rod-shaped bacterial strain, RL-2(T), was isolated from seawater of the East Sea in Korea and was subjected to a polyphasic taxonomic study. Strain RL-2(T) grew optimally at pH 7.5-8.0, at 20 °C and in the absence of NaCl. Phylogenetic trees based on 16S rRNA gene sequence analysis showed that strain RL-2(T) forms a cluster with Perlucidibaca piscinae IMCC1704(T) and various uncultured and unidentified gammaproteobacteria. Strain RL-2(T) exhibited 16S rRNA gene sequence similarity values of 96.1 % to Perlucidibaca piscinae IMCC1704(T) and 93.7-99.7 % to the uncultured bacterial clones belonging to the cluster and an unidentified gammaproteobacterium. The fatty acid profile of strain RL-2(T) was similar to that of Perlucidibaca piscinae IMCC1704(T), but the predominant ubiquinone type (Q-11) of strain RL-2(T) was different from that (Q-8) of Perlucidibaca piscinae IMCC1704(T). The DNA G+C content of strain RL-2(T) was 61.3 mol%. On the basis of phylogenetic, chemotaxonomic and phenotypic data, strain RL-2(T) is considered to represent a novel species of a new genus in the family Moraxellaceae, for which the name Paraperlucidibaca baekdonensis gen. nov., sp. nov. is proposed. The type strain of Paraperlucidibaca baekdonensis is RL-2(T) ( = KCTC 23145(T)  = CCUG 59307(T)).

Exploration of Csp genes from temperate and glacier soils of the Indian Himalayas and in silico analysis of encoding proteins.

The metagenomic Csp library was constructed from the temperate and glacier soils of central Himalaya, India followed by polymerase chain reaction (PCR) amplification. The library was further screened for low-temperature adaptation, and the positive recombinants were sorted out by determining changes in the melting temperature (Tm). A homology search of cloned sequence showed their identity with the Csp genes of Pseudomonas fluorescens, Psychrobacter cryohalolentis K5, and Shewanella spp MR-4. Amino acid sequence analysis annotated the presence of conserved aromatic and basic amino acids as well as RNA binding motifs from the cold shock domain. Furthermore, a PROSITE scan showed a moderate identity of less than 60% with the known cold shock-inducible proteins (ribosomal proteins, rbfA, DEAD-box helicases), cold acclimation protein, and temperature-induced protein (SRP1/TIP1). This study highlighted the prevalence of Csp genes from cold Himalayan environments that can be explored for tailor-made crop constructions in future.

Perlucidibaca piscinae gen. nov., sp. nov., a freshwater bacterium belonging to the family Moraxellaceae.

A freshwater bacterium, designated IMCC1704(T), was isolated from a eutrophic pond. The strain was Gram-negative, oxidase-positive, catalase-negative, chemoheterotrophic and facultatively aerobic with cells that were motile rods with a single polar flagellum. Based on 16S rRNA gene sequence similarity analyses, the novel strain was most closely related to the genera Alkanindiges (91.7%), Acinetobacter (89.0-91.2%), Moraxella (87.9-90.1%), Psychrobacter (87.2-89.5%) and Enhydrobacter (87.8%). Phylogenetic trees generated using 16S rRNA gene sequences showed that the novel isolate belonged to the family Moraxellaceae of the class Gammaproteobacteria and formed a distinct phyletic lineage within the family. The DNA G+C content of the strain was 63.1 mol% and the predominant constituents of the cellular fatty acids were C(16:1)omega7c and/or iso-C(15:0) 2-OH (21.2%), C(18:1)omega7c (12.8%) and C(12:0) 3-OH (12.3%). These chemotaxonomic properties, together with several phenotypic characteristics, differentiated the novel strain from other members of the family Moraxellaceae. From the taxonomic data, which revealed the distant relationship of the new strain to the related genera, the strain should be classified as a novel genus and species in the family Moraxellaceae, for which the name Perlucidibaca piscinae gen. nov., sp. nov. is proposed. The type strain of Perlucidibaca piscinae sp. nov. is IMCC1704(T) (=KCCM 42363(T)=NBRC 102354(T)).

Alkanindiges hongkongensis sp. nov. A novel Alkanindiges species isolated from a patient with parotid abscess.

A bacterium was isolated from the abscess pus of a 72-year-old patient with Warthin's tumor and parotid abscess. The cells were aerobic, non-motile, Gram-negative but difficult to be destained, non-sporulating, coccobacillus. The bacterium grew poorly on sheep blood agar and MacConkey agar as non-hemolytic colonies of 0.5 mm in diameter after 24h of incubation at 37 degrees C in ambient air. Growth was enhanced by Tween 80. It produces catalase but not cytochrome oxidase. Sequencing of the cloned 16S rRNA PCR products of the bacterium revealed three different 16S rRNA gene sequences, with 12 - 31 bp differences among them. Phylogenetic analysis showed that the bacterium is closely related to Alkanindiges illinoisensis, with 5.0 - 5.9% differences between the 16S rRNA gene sequence of the bacterium and that of A. illinoisensis. Tryptophan auxotrophic strain of Acinetobacter trpE27 transformed with DNA extracted from the bacterium was unable to grow on tryptophan deficient medium, indicating that the bacterium was not a strain of Acinetobacter. The G+C content of the bacterium (mean +/-SD) was 46.9+4.3%. A new species, Alkanindiges hongkongensis sp. nov., is proposed, for which HKU9T is the type strain. Isolates with "small colonies" that are apparently Acinetobacter-like species should be carefully identified. Growth enhancement with aliphatic hydrocarbons should be looked for and 16S rRNA gene sequencing performed in order to find more potential cases of Alkanindiges infections, as well as to define the epidemiology, clinical spectrum, and outcome of infections associated with this genus.

Psychrobacter nivimaris sp. nov., a heterotrophic bacterium attached to organic particles isolated from the South Atlantic (Antarctica).

An aggregate-attached bacterium, strain 88/2-7, was isolated from samples of the Southern Ocean and investigated in a polyphasic approach. The novel marine isolate is an aerobic, Gram-negative, oxidase- and catalase-positive, non-motile short rod and grows in form of cream-colored colonies. Growth was observed at 5-35 degrees C. The bacterium tolerated concentrations of 0-13% (w/v) NaCl and utilized a relatively restricted spectrum of carbon sources. The analysis of the fatty acids revealed 18:1 cis 9 (18:1omega9c) as main fatty acid. The G+C content of the DNA was approximately 42 mol%. The sequence of the 16S rDNA assigned strain 88/2-7 to the gamma-subclass of Proteobacteria with a similarity of 99.65% to Psychrobacter proteolyticus (DSM 13887T). A DNA-DNA-hybridization study showed only 26.8% renaturation to the respective strain. Based on the morphological, physiological and molecular properties of the new isolate, the name Psychrobacter nivimaris sp. nov. (type strain 88/2-7T) is proposed.