- Volume 61, Issue 8, 2011

A novel actinomycete, designated strain KLBMP 1256T, was isolated from a surface-sterilized stem of the oil-seed plant Jatropha curcas L. collected from Sichuan Province, south-west China, and was characterized to determine its taxonomic position. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the isolate was closely related to members of the genus Nocardia in the family Nocardiaceae, being most closely related to Nocardia callitridis CAP 290T (98.4 % similarity) and Nocardia nova JCM 6044T (97.5 %). Levels of 16S rRNA gene sequence similarity between strain KLBMP 1256T and the type strains of other recognized species of the genus Nocardia were less than 97 %. Chemotaxonomic data supported the affiliation of the new isolate to the genus Nocardia. However, the novel strain could be distinguished from its closest phylogenetic neighbour, N. callitridis CAP 290T, by a range of phenotypic properties. The combination of low DNA–DNA relatedness values and phenotypic differences from N. callitridis CAP 290T indicated that strain KLBMP 1256T represents a novel species of the genus Nocardia, for which the name Nocardia endophytica sp. nov. is proposed. The type strain is KLBMP 1256T ( = KCTC 19777T  = CCTCC AA 2010004T).

A previously undescribed, rapid-growing, non-chromogenic Mycobacterium isolate from a goat lung lesion in Algeria is reported. Biochemical and molecular tools were used for its complete description and showed its affiliation to the Mycobacterium terrae complex. 16S rRNA, rpoB and hsp65 gene sequences were unique. Phylogenetic analyses showed a close relationship with M. terrae sensu stricto and Mycobacterium senuense. Culture and biochemical characteristics were generally similar to those of M. terrae and M. senuense. However, in contrast to M. terrae and M. senuense, the isolate was positive for urease production and had faster growth. The mycolic acid profile was distinct from those of M. terrae and M. senuense, thus further supporting the new taxonomic position of the isolate. We propose the name Mycobacterium algericum sp. nov. for this novel species. The type strain is TBE 500028/10T ( = BejaiaT = CIP 110121T = DSM 45454T).

Seven isolates of a slowly growing, non-chromogenic Mycobacterium species were obtained from sputum and bronchial lavage fluid samples from elderly patients in different regions of Japan. These isolates were distinguished from related non-tuberculous species by colony morphology, positive results for Tween hydrolysis, catalase at 68 °C, nitrate reductase and pyrazinamidase and negative results for semi-quantitative catalase, urease and arylsulfatase. The mycolic acid pattern obtained by HPLC revealed a single cluster of late-eluting mycolic acids similar to but different from those of Mycobacterium malmoense ATCC 29571T. The 16S rRNA gene, 16S–23S internal transcribed spacer (ITS), rpoB and hsp65 sequences were unique in comparison with those of other mycobacteria. Comparison of 16S rRNA gene sequences showed that the isolates were most closely related to Mycobacterium tuberculosis H37RvT (21 base differences in 1508 bp; 98.6 % 16S rRNA gene sequence similarity). A representative strain, GTC 2738T, showed 91.9 % rpoB sequence similarity with Mycobacterium marinum strain M, 95 % hsp65 sequence similarity with Mycobacterium kansasii CIP 104589T and 81.1 % 16S–23S ITS sequence similarity with Mycobacterium gordonae ATCC 14470T. Phylogenetic analysis of concatenated sequences of the 16S rRNA, rpoB and hsp65 genes showed that strain GTC 2738T was located on a distinct clade adjacent to M. tuberculosis, M. ulcerans and M. marinum, with bootstrap values of 81 %. DNA–DNA hybridization demonstrated less than 70 % reassociation with type strains of genetically related species and supported the novel species status of the isolates. On the basis of this evidence, a novel species with the name Mycobacterium shinjukuense sp. nov. is proposed. The type strain, isolated from a sputum sample, is strain GTC 2738T( = JCM 14233T = CCUG 53584T).

Two novel Gram-reaction-positive, rod-shaped actinobacterial strains, designated RP-B26T and RP-B30T, were isolated from rhizosphere soil of a cliff-associated plant (Peucedanum japonicum Thunb.) which was collected from Mara Island, Republic of Korea. The colonies of the isolates were circular, smooth, convex and moderately yellow–light-yellow in colour. 16S rRNA gene sequence analysis revealed that the isolates belonged to the family Nocardioidaceae and formed two distinct sublineages within the radiation of the genus Nocardioides. 16S rRNA gene sequence similarity between the isolates was 98.2 %. The closest phylogenetic neighbours of strain RP-B26T were Nocardioides humi DCY24T and Nocardioides kongjuensis A2-4T with 97.4 and 97.0 % 16S rRNA gene sequence similarity, respectively, whereas 16S rRNA gene sequence similarities between strain RP-B30T and N. humi DCY24T and N. kongjuensis A2-4T were 96.5 and 96.0 %, respectively. Both of the isolates contained ll-diaminopimelic acid as the diagnostic diamino acid in the cell walls. The predominant menaquinone was MK-8(H4). The polar lipids were phosphatidylinositol and phosphatidylglycerol. The fatty acid profiles of the isolates were characterized by the presence of saturated, unsaturated, 10-methyl and hydroxyl fatty acids, with small amounts of branched fatty acids. The DNA G+C contents of strains RP-B26T and RP-B30T were 73.0 and 71.7 mol%, respectively. Levels of DNA–DNA relatedness between the isolates were 44.9±1.5 % (thermal renaturation method) and 43.2 % (photobiotin-labelled method); the isolates showed low DNA–DNA relatedness values (<11 %) to the most closely related strain, N. humi KCTC 19265T. On the basis of the phenotypic, genotypic and DNA–DNA hybridization data presented here, the isolates are considered to represent two novel species of the genus Nocardioides, for which the names Nocardioides ultimimeridianus sp. nov. (type strain RP-B26T  = KCTC 19368T  = DSM 19768T) and Nocardioides maradonensis sp. nov. (type strain RP-B30T  = KCTC 19384T  = DSM 19769T) are proposed.

A cold-tolerant, yellow-pigmented, Gram-positive, motile, facultatively anaerobic bacterial strain, LI1T, was isolated from a moss-covered soil from Livingston Island, Antarctica, near the Bulgarian station St. Kliment Ohridski. Comparative 16S rRNA gene sequence-based phylogenetic analysis placed the strain in a clade with the species Leifsonia kafniensis KFC-22T, Leifsonia pindariensis PON10T and Leifsonia antarctica SPC-20T, with which it showed sequence similarities of 99.0, 97.9 and 97.9 %, respectively. DNA–DNA hybridization revealed a reassociation value of 2.7 % with L. kafniensis LMG 24362T. The DNA G+C content of strain LI1T was 64.5 mol%. The growth temperature range was −6 to 28 °C, with optimum growth at 16 °C. Growth occurred in 0–5 % NaCl and at pH 4.5–9.5, with optimum growth in 1–2 % NaCl and at pH 5.5–6.5. The predominant fatty acids were anteiso-C15 : 0, C18 : 0 and iso-C15 : 0. The polar lipids were phosphatidylglycerol and diphosphatidylglycerol. Physiological and biochemical tests clearly differentiated strain LI1T from L. kafniensis. Therefore, a novel cold-tolerant species within the genus Leifsonia is proposed: Leifsonia psychrotolerans sp. nov. (type strain LI1T = DSM 22824T = NCCB 100313T).

A rod shaped, Gram-stain-negative, chemo-organotrophic, heterotrophic, strictly aerobic, non-gliding bacterium, designated strain PLRT, was isolated from faeces of the mollusc Aplysia punctata (Mollusca, Gastropoda) that had been fed with green algae belonging to the genus Ulva. The novel strain was able to degrade ulvan, a polysaccharide extracted from green algae (Chlorophyta, Ulvophyceae). The taxonomic position of strain PLRT was investigated by using a polyphasic approach. Strain PLRT was dark orange, oxidase-positive, catalase-positive and grew optimally at 25 °C, at pH 7.5 and in the presence of 2.5 % (w/v) NaCl with an oxidative metabolism using oxygen as the electron acceptor. Nitrate could not be used as the electron acceptor. Strain PLRT had a Chargaff’s coefficient (DNA G+C content) of 35.3 mol%. Phylogenetic analysis based on the sequence of the 16S rRNA gene placed the novel strain in the family Flavobacteriaceae (phylum ‘Bacteroidetes’), within a clade comprising Stenothermobacter spongiae, Nonlabens tegetincola, Sandarakinotalea sediminis, Persicivirga xylanidelens and Persicivirga dokdonensis. The closest neighbours of strain PLRT were P. xylanidelens and P. dokdonensis, sharing 95.2 and 95.5 % 16S rRNA gene sequence similarity, respectively. Phylogenetic inference and differential phenotypic characteristics demonstrated that strain PLRT represents a novel species of the genus Persicivirga, for which the name Persicivirga ulvanivorans sp. nov. is proposed. The type strain is PLRT ( = CIP 110082T = DSM 22727T).

A taxonomic study was carried out on two bacterial strains, PCP11T and PCP104, isolated from a tidal flat of the Yellow Sea, Korea. Comparative 16S rRNA gene sequence studies showed that these strains belonged to the family Cytophagaceae, phylum Bacteroidetes. Strains PCP11T and PCP104 shared 99.4 % sequence similarity and were related most closely to Reichenbachiella agariperforans KMM 3525T (95.8 and 96.0 % sequence similarity, respectively). Members of the genera Fulvivirga, Roseivirga, Fabibacter and Marinoscillum were the next closest relatives of the new isolates, with sequence similarities ≤91 %. The two isolates were Gram-staining-negative, strictly aerobic, gliding bacteria. They grew in the presence of 1–5 % NaCl, at pH 5.5–8.5 and at 4–35 °C. Strains PCP11T and PCP104 shared a number of physiological and biochemical properties with Reichenbachiella agariperforans KMM 3525T, but they differed from this strain in the hydrolysis of biopolymers and in the production of carotenoid and flexirubin-type pigments. Both strains possessed iso-C15 : 0, summed feature 4 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C15 : 0 as major cellular fatty acids. The major respiratory quinone was menaquinone 7 (MK-7). The G+C contents of the genomic DNA of strains PCP11T and PCP104 were 39.6 and 41.9 mol%, respectively. On the basis of phenotypic data and phylogenetic inference, it is proposed that the two isolates represent a novel species, Reichenbachiella faecimaris sp. nov., with strain PCP11T ( = KACC 14523T  = JCM 16588T) as the type strain. Emended descriptions of the genus Reichenbachiella and Reichenbachiella agariperforans are also proposed.

The whole-genome-sequenced rhizobacterium Bacillus amyloliquefaciens FZB42T (Chen et al., 2007) and other plant-associated strains of the genus Bacillus described as belonging to the species Bacillus amyloliquefaciens or Bacillus subtilis are used commercially to promote the growth and improve the health of crop plants. Previous investigations revealed that a group of strains represented a distinct ecotype related to B. amyloliquefaciens; however, the exact taxonomic position of this group remains elusive (Reva et al., 2004). In the present study, we demonstrated the ability of a group of Bacillus strains closely related to strain FZB42T to colonize Arabidopsis roots. On the basis of their phenotypic traits, the strains were similar to Bacillus amyloliquefaciens DSM 7T but differed considerably from this type strain in the DNA sequences of genes encoding 16S rRNA, gyrase subunit A (gyrA) and histidine kinase (cheA). Phylogenetic analysis performed with partial 16S rRNA, gyrA and cheA gene sequences revealed that the plant-associated strains of the genus Bacillus, including strain FZB42T, formed a lineage, which could be distinguished from the cluster of strains closely related to B. amyloliquefaciens DSM 7T. DNA–DNA hybridizations (DDH) performed with genomic DNA from strains DSM 7T and FZB42T yielded relatedness values of 63.7–71.2 %. Several methods of genomic analysis, such as direct whole-genome comparison, digital DDH and microarray-based comparative genomichybridization (M-CGH) were used as complementary tests. The group of plant-associated strains could be distinguished from strain DSM 7T and the type strain of B. subtilis by differences in the potential to synthesize non-ribosomal lipopeptides and polyketides. Based on the differences found in the marker gene sequences and the whole genomes of these strains, we propose two novel subspecies, designated B. amyloliquefaciens subsp. plantarum subsp. nov., with the type strain FZB42T ( = DSM 23117T = BGSC 10A6T), and B. amyloliquefaciens subsp. amyloliquefaciens subsp. nov., with the type strain DSM 7T( = ATCC 23350T = Fukumoto Strain FT), for plant-associated and non-plant-associated representatives, respecitvely. This is in agreement with results of DDH and M-CGH tests and the MALDI-TOF MS of cellular components, all of which suggested that the ecovars represent two different subspecies.

Nineteen thermophilic, aerobic, endospore-forming bacterial strains were subjected to 16S rRNA gene sequence analysis. Eight of these strains had been received as cultures of Geobacillus kaustophilus, G. lituanicus, G. stearothermophilus, ‘G. thermoleovorans subsp. stromboliensis’, G. vulcani, ‘Bacillus caldolyticus’, ‘B. caldotenax’ and ‘B. caldovelox’, but they showed close relationships with the type strain of G. thermoleovorans, as did two other strains received as G. thermoleovorans. All strains underwent further taxonomic analysis by API and other phenotypic tests and fatty acid methyl ester analysis, and selected strains were analysed for their polar lipids and for DNA relatedness. The 11 strains that formed the G. thermoleovorans 16S rRNA cluster also showed some phenotypic similarities, and DNA relatedness data support the reassignment of the strains received as G. kaustophilus, G. lituanicus, ‘G. thermoleovorans subsp. stromboliensis’, G. vulcani, ‘B. caldolyticus’, ‘B. caldotenax’ and ‘B. caldovelox’, and one of the G. stearothermophilus strains, as members of the species G. thermoleovorans. Four other strains received as G. kaustophilus were misnamed; two were identified as G. stearothermophilus and two appeared to be closely related to Anoxybacillus rupiensis. One strain received as G. stearothermophilus remained unidentified. On the basis of a single strain, Geobacillus thermocatenulatus was shown to represent a distinct species, but study of the type strain of Geobacillus gargensis showed this species to be a later heterotypic synonym of Geobacillus thermocatenulatus. Emended descriptions of Geobacillus thermoleovorans and Geobacillus thermocatenulatus are therefore presented.

A Gram-stain-positive, rod-shaped, yellow, non-motile, non-spore-forming, strictly aerobic bacterial strain, designated MW 10T, was isolated from seawater of the Bay of Bengal, India, and was subjected to a polyphasic taxonomic study. Analysis of the 16S rRNA gene sequence revealed that strain MW 10T showed highest similarity to the type strains of Psychrobacillus psychrodurans (96.15 %) and Psychrobacillus psychrotolerans (96.01 %) and showed less than 96 % similarity to members of the genera Paenisporosarcina, Planococcus, Sporosarcina and Planomicrobium. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain MW 10T formed a clade separate from members of closely related genera. The morphological, physiological and chemotaxonomic characteristics of strain MW 10T differed from those of members of closely related genera. The major fatty acid in strain MW 10T was iso-C15 : 0 and the menaquinones were MK-7 (48.4 %), MK-8 (32.3 %), MK-7(H2) (13.7 %) and MK-6 (5.6 %). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unknown phospholipid, an unknown lipid and an unknown glycolipid. The cell-wall peptidoglycan type was l-Lys–d-Asp. The genomic DNA G+C content (53.4 mol%) of strain MW 10T was significantly different from those of members of closely related genera. On the basis of its morphological, physiological and chemotaxonomic characteristics as well as our phylogenetic analysis, we conclude that strain MW 10T is a member of a novel genus and species, for which the name Chryseomicrobium imtechense gen. nov., sp. nov., is proposed. The type strain of Chryseomicrobium imtechense is MW 10T ( = MTCC 10098T  = JCM 16573T).

Using a polyphasic approach, a taxonomic study was performed on seven strains of an unknown Gram-reaction-positive, non-spore-forming, obligately anaerobic coccus-shaped bacterium, isolated from a swine-manure storage pit. Comparative 16S rRNA gene sequencing confirmed that all seven isolates were highly related to each other and formed a hitherto unknown lineage within the clostridial rRNA XI cluster of organisms. Pairwise analysis demonstrated that the novel organism was most closely related to Peptostreptococcus anaerobius CCUG 7835T and Peptostreptococcus stomatis CCUG 51858T with 16S rRNA gene sequence similarities of 95.5 and 93.0 %, respectively. The peptidoglycan type of the cell wall was determined to be A4α l-Lys–d-Asp and glucose, xylose and traces of mannose were detected as the cell–wall sugars. Based on biochemical, chemotaxonomic and phylogenetic evidence the unknown bacterium represents a new species of the genus Peptostreptococcus, for which the name Peptostreptococcus russellii sp. nov, is proposed. The type strain is RT-10BT ( = CCUG 58235T  = NRRL B-59380T  = DSM 23041T).

Alkaliphilic strains characterized by optimal growth at pH 9.0 and 5 % (w/v) NaCl designated K1-25T and H3-93 were isolated from extremely shallow soda ponds located in Hungary. Cells of both strains were Gram-stain-positive, non-motile, straight rods and formed central, ellipsoidal endospores with swollen sporangia. The isolates were aerobic, catalase-positive, oxidase-negative and contained a peptidoglycan of type A1γ based on meso-diaminopimelic acid. In both strains, menaquinone-7 (MK-7) was the predominant isoprenoid quinone and the major cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The DNA G+C contents of strains K1-25T and H3-93 were 39.0 and 36.3 mol%, respectively. 16S rRNA gene sequence-based phylogenetic analysis revealed 99.2 % similarity between strains K1-25T and H3-93 and the novel isolates had the highest similarities to Bacillus akibai 1139T (97.8 and 98.3 %, respectively), Bacillus wakoensis N-1T (97.0 and 97.4 %), Bacillus okhensis Kh10-101T (97.1 and 97.4 %) and Bacillus krulwichiae AM31DT (96.9 and 97.1 %). DNA–DNA hybridization between our strains and the type strains of closely related Bacillus species was lower than 70 %. Although DNA–DNA hybridization between strains K1-25T and H3-93 was 27 %, the phenotypic and chemotaxonomic data did not support the differentiation of these two strains into separate species. Therefore, they represent genomovars of a novel species, for which the name Bacillus alkalisediminis sp. nov. is proposed. The type strain is K1-25T ( = DSM 21670T  = NCAIM B02301T).

The species Lactococcus lactis currently includes three subspecies; L. lactis subsp. lactis and L. lactis subsp. cremoris, isolated from milk sources, and L. lactis subsp. hordniae, isolated from the leafhopper Hordnia circellata. In this study, three strains, designated L105T, I3 and L101, were isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). These strains were closely related to members of the species Lactococcus lactis. Strain L105T showed 99.4 % 16S rRNA gene sequence similarity to that of the type strains L. lactis subsp. lactis NCDO 604T and L. lactis subsp. hordniae NCDO 2181T and showed 99.9 % similarity to the type strain Lactococcus lactis subsp. cremoris NCDO 607T. Analysis of two housekeeping genes, rpoB and recA, confirmed the close relationship between the novel strains and L. lactis subsp. cremoris with similarities of 99.3 and 99.7 %, respectively. The three strains could, however, be differentiated from their closest relatives on the basis of several phenotypic characteristics, as was the case for L. lactis subsp. lactis and L. lactis subsp. hordniae, which were also closely related on the basis of 16S rRNA, rpoB and recA gene sequence similarities. The strains isolated in this study represent a new subspecies, for which the name Lactococcus lactis subsp. tructae subsp. nov. is proposed. The type strain is L105T ( = LMG 24662T  = DSM 21502T).

A Gram-positive-staining, aerobic, moderately halophilic bacterium, designated strain Y32T, was isolated from subsurface soil of the Sanwei salt field, Yancheng, Jiangsu province, South-east China. The cell-wall peptidoglycan type of strain Y32T was meso-diaminopimelic acid. The menaquinone was menaquinone-7 (MK-7). The major fatty acids were anteiso-C15 : 0 and iso-C15 : 0 and the DNA G+C content of strain Y32T was 40.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Y32T was closely related to the type strains of the genus Pontibacillus. The 16S rRNA gene sequence similarities of strain Y32T with the type strains of species of the genus Pontibacillus were 97.8 % (Pontibacillus marinus KCTC 3917T), 96.9 % (Pontibacillus chungwhensis BH030062T), 96.8 % (Pontibacillus litoralis JSM 072002T) and 96.0 % (Pontibacillus halophilus JSM 076056T). DNA–DNA relatedness between strain Y32T and P. marinus KCTC 3917T was 42 %. On the basis of phenotypic, chemotaxonomic and phylogenetic evidences, strain Y32T was found to be affiliated to the genus Pontibacillus, but was clearly differentiated from other members of this genus. Strain Y32T represents a novel member of the genus, for which the name Pontibacillus yanchengensis sp. nov. is proposed. The type strain is Y32T ( = CGMCC 1.10680T = CCTCC AB209311T = NRRL B-59408T).

A polyphasic taxonomic study was performed on 22 thermotolerant, aerobic, endospore-forming bacteria from dairy environments. Seventeen isolates were retrieved from raw milk, one from a filter cloth and four from grass, straw or milking equipment. These latter four isolates (R-6546, R-7499, R-7764 and R-7440) were identified as Bacillus thermoamylovorans based on DNA–DNA hybridizations (values above 70 % with Bacillus thermoamylovorans LMG 18084T) but showed discrepancies in characteristics with the original species description, so an emended description of this species is given. According to 16S rRNA gene sequence analysis and DNA–DNA hybridization experiments, the remaining 18 isolates (R-6488T, R-28193, R-6491, R-6492, R-7336, R-33367, R-6486, R-6770, R-31288, R-28160, R-26358, R-7632, R-26955, R-26950, R-33520, R-6484, R-26954 and R-7165) represented one single species, most closely related to Bacillus thermoamylovorans (93.9 % 16S rRNA gene sequence similarity), for which the name Bacillus thermolactis is proposed. Cells were Gram-stain-positive, facultatively anaerobic, endospore-forming rods that grew optimally at 40–50 °C. The cell wall peptidoglycan type of strain R-6488T, the proposed type strain, was A1γ based on meso-diaminopimelic acid. Major fatty acids of the strains were C16 : 0 (28.0 %), iso-C16 : 0 (12.1 %) and iso-C15 : 0 (12.0 %). MK-7 was the predominant menaquinone, and major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and some unidentified phospholipids. DNA G+C content was 35.0 mol%. Phenotypic properties allowed discrimination from other thermotolerant species of the genus Bacillus and supported the description of the novel species Bacillus thermolactis, with strain R-6488T ( = LMG 25569T  = DSM 23332T) as the proposed type strain.

Strain NRRL B-23883T was isolated from retail ground beef as part of a study on the genetic diversity of Clostridium perfringens. The strain was found to be a strictly anaerobic, Gram-positive coccus that was able to utilize peptone as a sole carbon source. Analysis of the 16S rRNA gene sequence revealed that the strain was closely related to species within the genera Peptoniphilus and Anaerosphaera, but it was substantially different from the closest recognized species by nearly 10 % sequence divergence. The strain was also found to be closely related (>99 % sequence similarity) to an uncultured bacterial strain that was sequenced from a 16S rRNA gene clone library constructed to characterize the bacterial community of faeces from a captive spotted hyena. Strain NRRL B-23883T shared the peptidoglycan type A4β, l-Orn–d-Glu with members of the genus Peptoniphilus. Further phenotypic analysis revealed that strain NRRL B-23883T was able to utilize glycyl l-methionine as a sole carbon source, in contrast to other species of the genus Peptoniphilus. Therefore, it is proposed that the isolate represents a novel species, Peptoniphilus methioninivorax sp. nov.; the type strain is NRRL B-23883T ( = DSM 22461T).