Pseudochrobactrum algeriensis sp. nov., isolated from lymph nodes of Algerian cattle.

Three Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile strains (C130915_07T, C150915_16 and C150915_17) were isolated from lymph nodes of Algerian cows. On the basis of 16S rRNA gene and whole genome similarities, the isolates were almost identical and clearly grouped in the genus Pseudochrobactrum. This allocation was confirmed by the analysis of fatty acids (C19:cyclo, C18 : 1, C18 : 0, C16 : 1 and C16 : 0) and of polar lipids (major components: phosphatidylethanolamine, ornithine-lipids, phosphatidylglycerol, cardiolipin and phosphatidylcholine, plus moderate amounts of phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine and other aminolipids). Genomic, physiological and biochemical data differentiated these isolates from previously described Pseudochrobactrum species in DNA relatedness, carbon assimilation pattern and growth temperature range. Thus, these organisms represent a novel species of the genus Pseudochrobactrum, for which the name Pseudochrobactrum algeriensis sp. nov. is proposed (type strain C130915_07T=CECT30232T=LMG 32378T).

Falsochrobactrum shanghaiense sp. nov., isolated from paddy soil and emended description of the genus Falsochrobactrum.

A non-spore-forming, motile, Gram-stain-negative, short rod-shaped strain, designated HN4T, was isolated from a paddy soil sample collected in Shanghai, China. A comparative analysis o-f 16S rRNA gene sequences showed that strain HN4T fell within the genus Falsochrobactrum, forming a clear cluster with the type strain of Falsochrobactrum ovis, with which it exhibited a 16S rRNA gene sequence similarity value of 98.2 %. Strain HN4T grew optimally at pH 7.0, 30-35 °C and in the presence of 1 % (w/v) NaCl. It was positive for oxidase activity. Chemotaxonomic analysis showed that strain HN4T contained ubiquinone-10 as the predominant respiratory quinone and possessed summed feature 8(C18 : 1ω7c and/or C18 : 1ω6c) and C19 : 0cyclo ω8c as predominant fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G+C content was 56.9 mol%. Strain HN4T exhibited a DNA-DNA relatedness level of 18±1 % with Falsochrobactrum ovis CCM 8460T. Based on the data obtained in this study, strain HN4T represents a novel species of the genus Falsochrobactrum, for which the name Falsochrobactrumshanghaiense sp. nov. is proposed. The type strain is HN4T (=JCM 32785T=CCTCC AB 2018063T).

Brucella spp. of amphibians comprise genomically diverse motile strains competent for replication in macrophages and survival in mammalian hosts.

Twenty-one small Gram-negative motile coccobacilli were isolated from 15 systemically diseased African bullfrogs (Pyxicephalus edulis), and were initially identified as Ochrobactrum anthropi by standard microbiological identification systems. Phylogenetic reconstructions using combined molecular analyses and comparative whole genome analysis of the most diverse of the bullfrog strains verified affiliation with the genus Brucella and placed the isolates in a cluster containing B. inopinata and the other non-classical Brucella species but also revealed significant genetic differences within the group. Four representative but molecularly and phenotypically diverse strains were used for in vitro and in vivo infection experiments. All readily multiplied in macrophage-like murine J774-cells, and their overall intramacrophagic growth rate was comparable to that of B. inopinata BO1 and slightly higher than that of B. microti CCM 4915. In the BALB/c murine model of infection these strains replicated in both spleen and liver, but were less efficient than B. suis 1330. Some strains survived in the mammalian host for up to 12 weeks. The heterogeneity of these novel strains hampers a single species description but their phenotypic and genetic features suggest that they represent an evolutionary link between a soil-associated ancestor and the mammalian host-adapted pathogenic Brucella species.

Paenochrobactrum pullorum sp. nov. isolated from a chicken.

A Gram-stain-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (strain 280(T)) isolated from a chicken was studied for its taxonomic allocation. 16S rRNA gene sequence analyses clearly allocated the isolate in the genus Paenochrobactrum group with a 16S rRNA gene sequence similarity of 98.8% to the currently recognized species, Paenochrobactrum gallinarii and Paenochrobactrum glaciei. This allocation was confirmed by the fatty acid data (major fatty acids: C18:1ω7c and C19:0 cyclo ω8c) and a polyamine pattern with the major compound putrescine and relatively high amounts of spermidine. Also, the polar lipid profile with phosphatidylethanolamine, phosphatiylmonomethylethanolamine, phosphatidylglycerol, phosphatidylcholine and the genus-specific 'stretched aminolipid' was well in line with the description of the genus Paenochrobactrum. The quinone system consisted predominantly of ubiquinone Q-10 with traces of Q-9 and Q-11. DNA-DNA hybridization of strain 280T with Paenochrobactrum gallinarii Sa25T and Paenochrobactrum glaciei KMM 3858T showed relatedness values of 38.8% (reciprocal 20.2%) and 30.2% (reciprocal 29.8%), respectively. These results in combination with differentiating physiological and biochemical data clearly showed that strain 280T merits species status. We propose the name Paenochrobactrum pullorum sp. nov. to accommodate this strain with the type strain 280T (=LMG 28095T=CIP 110700T).

Cr(VI) resistance and removal by indigenous bacteria isolated from chromium-contaminated soil.

The removal of toxic Cr(VI) by microorganisms is a promising approach for Cr(VI) pollution remediation. In the present study, four indigenous bacteria, named LY1, LY2, LY6, and LY7, were isolated from Cr(VI)-contaminated soil. Among the four Cr(VI)-resistant isolates, strain LY6 displayed the highest Cr(VI)-removing ability, with 100 mg/l Cr(VI) being completely removed within 144 h. It could effectively remove Cr(VI) over a wide pH range from 5.5 to 9.5, with the optimal pH of 8.5. The amount of Cr(VI) removed increased with initial Cr(VI) concentration. Data from the time-course analysis of Cr(VI) removal by strain LY6 followed first-order kinetics. Based on the 16S rRNA gene sequence, strain LY6 was identified as Pseudochrobactrum asaccharolyticum, a species that had never been reported for Cr(VI) removal before. Transmission electron microscopy and energy dispersive X-ray spectroscopy analysis further confirmed that strain LY6 could accumulate chromium within the cell while conducting Cr(VI) removal. The results suggested that the indigenous bacterial strain LY6 would be a new candidate for potential application in Cr(VI) pollution bioremediation.

Paenochrobactrum gallinarii gen. nov., sp. nov., isolated from air of a duck barn, and reclassification of Pseudochrobactrum glaciei as Paenochrobactrum glaciei comb. nov.

A Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (Sa25(T)) was isolated from air of a duck barn. 16S rRNA gene and recA sequence analyses clearly placed the isolate in the vicinity of the Brucella-Ochrobactrum-Pseudochrobactrum group, with the closest relative being Pseudochrobactrum glaciei KMM 3858(T). This allocation was confirmed by analyses of the quinone system (ubiquinone Q-10), fatty acid data (major fatty acids C(18 : 1)omega7c and C(19 : 0) cyclo omega8c) and polar lipid profile (major components diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and unknown aminolipid AL1; moderate amounts of three unknown polar lipids, L1-L3, an unknown aminolipid and an unknown aminophospholipid APL2). The polyamine pattern of Sa25(T) exhibited the major compound putrescine and moderate amounts of spermidine; a similar polyamine pattern with the major compound putrescine was also detected in Pseudochrobactrum glaciei KMM 3858(T). DNA-DNA hybridization of strain Sa25(T) with Pseudochrobactrum glaciei KMM 3858(T) and the type strains of the other Pseudochrobactrum species showed values ranging from 50.3 to 24.8 %, and physiological and biochemical data clearly differentiated this isolate from the described Pseudochrobactrum species. Since Sa25(T) and Pseudochrobactrum glaciei KMM 3858(T) form a distinct lineage in the 16S rRNA gene sequence-based phylogenetic tree, and this separate position is supported by unique characteristics of their polyamine patterns and polar lipid profiles, we propose the novel genus Paenochrobactrum gen. nov., with the type species Paenochrobactrum gallinarii sp. nov. (type strain Sa25(T) =CCUG 57736(T) =CCM 7656(T)) and the reclassification of Pseudochrobactrum glaciei as Paenochrobactrum glaciei comb. nov. (type strain Pi26(T) =KMM 3858(T) =NRIC 0733(T) =JCM 15115(T)).

Brevundimonas naejangsanensis sp. nov., a proteolytic bacterium isolated from soil, and reclassification of Mycoplana bullata into the genus Brevundimonas as Brevundimonas bullata comb. nov.

A Gram-negative, motile and rod-shaped bacterial strain, BIO-TAS2-2(T), of the class Alphaproteobacteria, was isolated from a soil in Korea and studied using a polyphasic taxonomic approach. Strain BIO-TAS2-2(T) grew optimally at pH 7.5-8.5 and 30 degrees C and in the presence of 0-1.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain BIO-TAS2-2(T) fell within the clade comprising species of the genus Brevundimonas, forming a coherent cluster with Brevundimonas terrae KSL-145(T) and Brevundimonas diminuta LMG 2089(T). It exhibited 16S rRNA gene sequence similarity values of 96.0-98.7 % to members of the genus Brevundimonas and Mycoplana bullata IAM 13153(T). Strain BIO-TAS2-2(T) contained Q-10 as the predominant ubiquinone and cyclo-C(18 : 1)omega7c and C(16 : 0) as the major fatty acids. The DNA G+C content was 67.0 mol%. Strain BIO-TAS2-2(T) exhibited DNA-DNA relatedness levels of 12-19 % with the type strains of phylogenetically related Brevundimonas species and M. bullata. The novel strain could be differentiated from Brevundimonas species and M. bullata by differences in phenotypic characteristics. On the basis of phenotypic, phylogenetic and genetic data, strain BIO-TAS2-2(T) is considered to represent a novel species of the genus Brevundimonas, for which the name Brevundimonas naejangsanensis sp. nov. is proposed. The type strain is BIO-TAS2-2(T) (=KCTC 22631(T)=CCUG 57609(T)). In this study, it is also proposed that Mycoplana bullata be transferred to the genus Brevundimonas as Brevundimonas bullata comb. nov. (type strain TK0051(T)=ATCC 4278(T)=DSM 7126(T)=JCM 20846(T)=LMG 17157(T)).

Pseudochrobactrum lubricantis sp. nov., isolated from a metal-working fluid.

A Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (KSS 7.8(T)) was isolated from a water-mixed metal-working fluid. On the basis of 16S rRNA gene and recA sequence similarities, the isolate was clearly grouped in the genus Pseudochrobactrum. This allocation was confirmed by fatty acid data (major fatty acids: C(18 : 2)omega7c and C(19 : 0) cyclo omega8c), polar lipid profile (major components: phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine, plus moderate amounts of phosphatidylmonomethylethanolamine and unknown aminolipid AL1), quinone system (ubiquinone Q-10) and polyamine pattern (spermidine and putrescine predominant). DNA-DNA pairing with the most closely related Pseudochrobactrum species showed values ranging from 24.2 to 45.7 %, and physiological and biochemical data clearly differentiated this isolate from described Pseudochrobactrum species. This organism represents a novel species of the genus Pseudochrobactrum, for which the name Pseudochrobactrum lubricantis sp. nov. is proposed, with the type strain KSS 7.8(T) (=CCUG 56963(T)=CCM 7581(T)).

Pseudochrobactrum glaciei sp. nov., isolated from sea ice collected from Peter the Great Bay of the Sea of Japan.

An aerobic, Gram-negative, non-pigmented, non-motile bacterium, KMM 3858(T), was isolated from a sea-ice sample collected from Peter the Great Bay of the Sea of Japan, Russia, and subjected to a phenotypic and phylogenetic study. Comparative analyses based on the 16S rRNA and recA gene sequences placed strain KMM 3858(T) within the genus Pseudochrobactrum. The major chemotaxonomic characteristics were found to be the presence of phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unknown aminolipid and phosphatidylcholine, major fatty acids C(18 : 1)omega7c and C(19 : 0) cyclo, and ubiquinone Q-10, confirming the affiliation of strain KMM 3858(T) to the genus Pseudochrobactrum. On the basis of the phylogenetic analysis and the physiological and biochemical characterization, strain KMM 3858(T) should be classified as representing a novel species of the genus Pseudochrobactrum, for which the name Pseudochrobactrum glaciei sp. nov. is proposed. The type strain is strain Pi26(T) (=KMM 3858(T)=NRIC 0733(T)=JCM 15115(T)).

Daeguia caeni gen. nov., sp. nov., isolated from sludge of a textile dye works.

A Gram-negative, non-spore-forming, rod-shaped bacterial strain, K107(T), was isolated from sludge collected from a textile dye works in Korea and its taxonomic position was investigated by means of a polyphasic analysis. Strain K107(T) contained Q-10 as the predominant ubiquinone. The major fatty acids (>10% of total fatty acids) were C(18:1)omega7c and C(18:1) 2-OH. The DNA G+C content was 57.0 mol%. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain K107(T) was closely related to the genera Mycoplana, Brucella and Ochrobactrum. Strain K107(T) exhibited 16S rRNA gene sequence similarity values of 96.3-97.1% with respect to the type strains of two Mycoplana species and 94.8-96.8% with respect to members of the genera Brucella and Ochrobactrum. A phylogenetic analysis based on recA gene sequences showed that strain K107(T) forms a distinct phylogenetic lineage within the Alphaproteobacteria. The recA gene sequence of strain K107(T) showed similarity values of 84.5% with respect to type strains of Brucella species and values of 77.6-83.1% with respect to members of the genera Pseudochrobactrum, Ochrobactrum and Mycoplana. Strain K107(T) could be differentiated from phylogenetically related genera by differences in phenotypic properties and fatty acid profiles. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain K107(T) represents a novel genus and species, for which the name Daeguia caeni gen. nov., sp. nov. is proposed. The type strain of Daeguia caeni is strain K107(T) (=KCTC 12981(T) =CCUG 54520(T)).

Description of Pseudochrobactrum kiredjianiae sp. nov.

A Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacterium (strain CCUG 49584(T)), isolated from a seafood processing plant sample in New Zealand, was subjected to a polyphasic taxonomic study. On the basis of 16S rRNA and recA gene sequence similarities, the isolate was allocated to the genus Pseudochrobactrum. This was confirmed by fatty acid data (major fatty acids: C(18 : 1)omega7c and C(19 : 0) cyclo omega8c), a polar lipid profile exhibiting major characteristics of Pseudochrobactrum (phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine), quinone system Q-10 and a polyamine pattern with the predominant compounds spermidine and putrescine. DNA-DNA hybridization with the type strains of the two established species of Pseudochrobactrum and physiological and biochemical data clearly differentiated the isolate from established Pseudochrobactrum species. As a consequence, this organism represents a novel species, for which the name Pseudochrobactrum kiredjianiae sp. nov. is proposed, with the type strain CCUG 49584(T) (=CIP 109227(T)).