- Volume 60, Issue 9, 2010

A Gram-negative, rod-shaped, non-spore-forming bacterial strain, designated LMG 2337T, was isolated from the blood of a patient with endocarditis and characterized. The strain was affiliated with the alphaproteobacterial genus Brevundimonas, with Brevundimonas diminuta LMG 2089T (98.3 % 16S rRNA gene sequence similarity) and Brevundimonas terrae KSL-145T (97.5 %) as its closest relatives. This affiliation was supported by chemotaxonomic data: the G+C content was 66.3 mol %, the major polar lipids were phosphatidyl diacylglycerol, sulfoquinovosyl diacylglycerol and phosphatidyl glucopyranosyl diacylglycerol and the major fatty acids were summed feature 7 (one or more of C18 : 1 ω7c, C18 : 1 ω9t and C18 : 1 ω12t) and C16 : 0. Strain LMG 2337T displayed an unusually broad substrate spectrum. The results from DNA–DNA hybridization and physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain LMG 2337T from all of the type strains of hitherto-described Brevundimonas species. The strain therefore represents a novel species, for which the name Brevundimonas vancanneytii sp. nov. is proposed, with type strain LMG 2337T (=CCUG 1797T =ATCC 14736T).

The alphaproteobacterial strains GRP21T and PH34, which were isolated from coastal sediment of the East Sea, Korea, were subjected to a polyphasic taxonomic investigation. The strains were Gram-negative, non-motile, non-spore-forming, oval-shaped rods that produced creamy-white colonies on tryptic soy agar, required NaCl for growth, contained Q-10 as the predominant ubiquinone, contained 16 : 0, 18 : 1ω7c and 19 : 0 cyclo ω8c as major fatty acids and had polar lipid profiles consisting of phosphatidylcholine, phosphatidylglycerol, an unknown aminolipid, an unknown phospholipid and three unknown lipids. Phylogenetic analysis, based on 16S rRNA gene sequencing, showed that the strains were most closely related to Donghicola eburneus KCTC 12735T, with 94.5 % sequence similarity, but formed a separate lineage within the family Rhodobacteraceae. The combined genotypic and phenotypic data supported the conclusion that the strains represent a novel genus and species, for which the name Pontibaca methylaminivorans gen. nov., sp. nov. is proposed. The type strain of Pontibaca methylaminivorans is GRP21T (=KCTC 22497T =DSM 21219T).

A strictly aerobic, Gram-negative, non-pigmented bacterial strain, designated LMEB 39T, was isolated from a seawater sample collected from the Yangtze River estuary near the East China Sea and was examined physiologically, chemotaxonomically and phylogenetically. The novel isolate was motile by a single polar flagellum and positive for nitrate reduction and decomposition of casein, gelatin, Tween 20 and Tween 80, but negative for indole production. Chemotaxonomic analysis revealed ubiquinone-8 as the predominant respiratory quinone and phosphatidylethanolamine and phosphatidylglycerol as major polar lipids. The major fatty acids were C16 : 1 ω7c/iso-C15 : 0 2-OH, C16 : 0, C18 : 1 ω7c, C12 : 0 3-OH, C17 : 1 ω8c and C17 : 0. The genomic DNA G+C content was 42.3 mol%. Comparative 16S rRNA gene sequence analysis revealed that the isolate belongs to the genus Pseudoalteromonas. Strain LMEB 39T exhibited the closest phylogenetic affinity to Pseudoalteromonas byunsanensis JCM 12483T (97.4 % sequence similarity). The DNA–DNA reassociation values between strain LMEB 39T and P. byunsanensis JCM 12483T and Pseudoalteromonas undina DSM 6065T (97.2 % sequence similarity) were 31.7 and 30.3 %, respectively. On the basis of phenotypic and genotypic data, strain LMEB 39T represents a novel species of the genus Pseudoalteromonas, for which the name Pseudoalteromonas lipolytica sp. nov. is proposed; the type strain is LMEB 39T (=CGMCC 1.8499T=JCM 15903T).

Strain BL06T was isolated from landfill soil in Pohang, Korea. Strain BL06T is Gram-negative, aerobic, non-motile and rod-shaped. For growth, the NaCl range is 0–6 % (w/v), the temperature range is 10–44 °C and the pH range is 5.5–12.0. Based on the 16S rRNA gene and gyrase B (gyrB) gene sequences, phylogenetic analysis showed that strain BL06T is associated with the genus Alishewanella and related closely to the type strains of Alishewanella species (98.8 % 16S rRNA gene sequence similarity to Alishewanella aestuarii, 98.7 % to Alishewanella fetalis and 98.5 % to Alishewanella jeotgali). Physiological and biochemical tests verified that strain BL06T is genotypically and phenotypically different from previously described species in the genus Alishewanella. DNA–DNA hybridization experiments showed that relatedness between the genomic DNA of strain BL06T and type strains of other Alishewanella species is <41 %. These findings suggest strongly that the strain represents a novel species, despite high 16S rRNA gene sequence similarity between strain BL06T and related strains. Therefore, strain BL06T (=KCTC 22400T=JCM 15597T) is proposed to represent a novel species in the genus Alishewanella, named Alishewanella agri sp. nov.

A novel Gram-negative, orange-pigmented, slightly halophilic, rod-shaped bacterium, strain T30T, was isolated from sediment from the South China Sea. Phylogenetic analysis showed that strain T30T was a member of the genus Erythrobacter, sharing highest 16S rRNA gene sequence similarities with Erythrobacter aquimaris JCM 12189T (99.5 %) and Erythrobacter vulgaris DSM 17792T (99.0 %). Levels of DNA–DNA relatedness between strain T30T and closely related strains of Erythrobacter species ranged from 14.5 to 56.9 %.The isolate lacked bacteriochlorophyll a and contained ubiquinone-10 as the predominant respiratory lipoquinone. The major fatty acids of this strain were C18 : 1 ω7c (38.2 %) and C16 : 1 ω7c /C16 : 1 ω6c (17.4 %). The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine and phosphatidylglycerol. The DNA G+C content of strain T30T was 59.5 mol%. On the basis of phenotypic and phylogenetic data, a novel species, Erythrobacter nanhaisediminis sp. nov., is proposed; the type strain is T30T (=CGMCC 1.7715T=JCM 16125T).

Monoxenous trypanosomatid Herpetomonas trimorpha sp. nov. was isolated from the digestive tract of the biting midge Culicoides truncorum (Ceratopogonidae, Diptera). This species forms three distinct morphotypes in culture: the microflagellate promastigote, the small promastigote and the long promastigote. The last form is unique for the newly described species. Phylogenetic analyses of SSU rRNA and glycosomal glyceraldehyde phosphate dehydrogenase genes showed that H. trimorpha sp. nov. is the closest relative of Herpetomonas ztiplika, another monoxenous trypanosomatid isolated from biting midges. However, morphological and randomly amplified polymorphic DNA analyses confirmed that H. trimorpha sp. nov. is distinct from H. ztiplika.

Six strains of a novel yeast species were isolated from Nothofagus species trees in native forests in Patagonia, Argentina. The strains were isolated from bark, fluxes and the ectomycorrhizospheric soil fraction of Nothofagus antarctica, Nothofagus nervosa and Nothofagus pumilio. Analysis of the D1/D2 large-subunit rDNA sequences indicated that the novel species belonged to the genus Lachancea and is closely related to Lachancea meyersii. The name Lachancea nothofagi sp. nov. is proposed to accommodate these strains. The type strain is UWOPS 99-807.3T (=CBS 11611T=NRRL Y-48670T).

A basidiomycetous yeast, strain CRUB 1032T, which formed salmon-pink colonies, was isolated from glacial meltwater in Patagonia, Argentina. Morphological, physiological and biochemical characterization indicated that this strain belonged to the genus Rhodotorula. Molecular taxonomic analysis based on the 26S rDNA D1/D2 domain and internal transcribed spacer region sequences showed that strain CRUB 1032T represents an undescribed yeast species, for which the name Rhodotorula meli sp. nov. is proposed (type strain is CRUB 1032T=CBS 10797T=JCM 15319T). Phylogenetic analysis showed that Rhodotorula lamellibrachii was the closest known species, which, together with R. meli, formed a separate cluster related to the Sakaguchia clade within the Cystobasidiomycetes. Additional Patagonian yeast isolates of the class Cystobasidiomycetes are also investigated in the present work.

Partial sequences of the recN gene (1249 bp), which encodes a recombination and repair protein, were analysed to determine the phylogenetic relationship and identification of streptococci. The partial sequences presented interspecies nucleotide similarity of 56.4–98.2 % and intersubspecies similarity of 89.8–98 %. The mean DNA sequence similarity of recN gene sequences (66.6 %) was found to be lower than those of the 16S rRNA gene (94.1 %), rpoB (84.6 %), sodA (74.8 %), groEL (78.1 %) and gyrB (73.2 %). Phylogenetically derived trees revealed six statistically supported groups: Streptococcus salivarius, S. equinus, S. hyovaginalis/S. pluranimalium/S. thoraltensis, S. pyogenes, S. mutans and S. suis. The ‘mitis’ group was not supported by a significant bootstrap value, but three statistically supported subgroups were noted: Streptococcus sanguinis/S. cristatus/S. sinensis, S. anginosus/S. intermedius/S. constellatus (the ‘anginosus’ subgroup) and S. mitis/S. infantis/S. peroris/S. oralis/S. oligofermentans/S. pneumoniae/S. pseudopneumoniae. The partial recN gene sequence comparison highlighted a high percentage of divergence between Streptococcus dysgalactiae subsp. dysgalactiae and S. dysgalactiae subsp. equisimilis. This observation is confirmed by other gene sequence comparisons (groEL, gyrB, rpoB and sodA). A high percentage of similarity was found between S. intermedius and S. constellatus after sequence comparison of the recN gene. To study the genetic diversity among the ‘anginosus’ subgroup, recN, groEL, sodA, gyrB and rpoB sequences were determined for 36 clinical isolates. The results that were obtained confirmed the high genetic diversity within this group of streptococci.