Kikue Hirota

Alkalibacterium indicireducens sp. nov., an obligate alkaliphile that reduces indigo dye.

Indigo-reducing, obligately alkaliphilic strains A11T, F11 and F12 were isolated from indigo fermentation liquor obtained from Tokushima Prefecture, Shikoku, Japan. The isolates grew at pH 9.0-12.3, but not at pH 7.0-8.0. The optimum pH range for growth was 9.5-11.5. They were Gram-negative, facultatively anaerobic, rod-shaped strains with peritrichous flagella. The isolates grew in 0-14 % (w/v) NaCl, with optimum growth at 1-11 %. They grew at temperatures of 15-35 degrees C with optimum growth at around 20-30 degrees C. dl-Lactate was the major end product from d-glucose. No quinones were detected. The peptidoglycan type was A4 alpha, l-Lys (l-Orn)-d-Asp. The major cellular fatty acids were C16 : 0, C16 : 17c and C18 : 19c. The DNA G+C contents were 47.0-47.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequence data indicated that the isolates belong to the genus Alkalibacterium. DNA-DNA hybridization revealed low relatedness values between the isolates and the three phylogenetically most closely related species, Alkalibacterium olivapovliticus, Alkalibacterium psychrotolerans and Alkalibacterium iburiense (<41 %). On the basis of phenotypic characteristics, including hydrolysis of cellulose and fermentation of carbohydrates, and chemotaxonomic characteristics, phylogenetic data and DNA-DNA relatedness data, it is concluded that the isolates merit classification as representatives of a novel species of the genus Alkalibacterium, for which the name Alkalibacterium indicireducens sp. nov. is proposed. The type strain of this species is A11T (=JCM 14232T=NCIMB 14253T).

Bacillus polygoni sp. nov., a moderately halophilic, non-motile obligate alkaliphile isolated from indigo balls.

A moderately halophilic, obligate alkaliphile (growth range pH 8-12), designated strain YN-1(T), was isolated from indigo balls obtained from Ibaraki, Japan. The cells of the isolate stained Gram-positive, and were aerobic, non-motile, sporulating rods which grew optimally at pH 9. The strain grew in 3-14% NaCl with optimum growth in 5% NaCl. It hydrolysed casein and Tweens 20, 40 and 60, but not gelatin, starch, DNA or pullulan. Its major isoprenoid quinone was MK-7 and its cellular fatty acid profile mainly consisted of anteiso-C(15:0), anteiso-C(17:0) and anteiso-C(17:1). 16S rRNA phylogeny suggested that strain YN-1(T) was a member of group 7 (alkaliphiles) of the genus Bacillus, with the closest relative being Bacillus clarkii DSM 8720(T) (similarity 99.5%). However, DNA-DNA hybridization showed a low DNA-DNA relatedness (7%) of strain YN-1(T) with B. clarkii DSM 8720(T). Owing to the significant differences in phenotypic and chemotaxonomic characteristics, and phylogenetic and DNA-DNA relatedness data, the isolate merits classification as a new species, for which the name Bacillus polygoni is proposed. The type strain of this species is YN-1(T) (=JCM 14604(T)=NCIMB 14282(T)).

Oceanobacillus indicireducens sp. nov., a facultative alkaliphile that reduces an indigo dye

An indigo-reducing facultatively alkaliphilic and halophilic strain, designated strain A21(T), was isolated from a fermented Polygonum indigo (Polygonum tinctorium Lour.) liquor sample aged for 4 days prepared in a laboratory. 16S rRNA gene sequence phylogeny suggested that strain A21(T) was a member of the genus Oceanobacillus with the closest relative being the type strain of Oceanobacillus chironomi (similarity: 96.0 %). The cells of the isolate stained Gram-positive and were facultatively anaerobic straight rods that were motile by peritrichous flagella. The strain grew between 18 and 48 °C with optimum growth at 39 °C. It grew in the pH range of 7-12. It hydrolysed casein, gelatin and Tween 20 but not Tweens 40, 60 and 80, starch or DNA. No isoprenoid quinone was detected and the DNA G+C content was 39.7 mol%. The whole-cell fatty acid profile mainly consisted of iso-C15 : 0, anteiso-C15 : 0 and C16 : 0. DNA-DNA hybridization experiments with O. chironomi revealed 13 % relatedness. Owing to the differences in phenotypic and chemotaxonomic characteristics, and phylogenetic analyses based on 16S rRNA gene sequences and DNA-DNA relatedness data from reported Oceanobacillus species, the isolate merits classification as a representative of a novel species, for which the name Oceanobacillus indicireducens sp. nov. is proposed. The type strain is A21(T) ( = JCM 17251(T)  = NCIMB 14685(T)). The description of the genus Oceanobacillus is also emended.

Pseudomonas toyotomiensis sp. nov., a psychrotolerant facultative alkaliphile that utilizes hydrocarbons

A psychrotolerant, facultatively alkaliphilic strain, HT-3(T), was isolated from a sample of soil immersed in hot-spring water containing hydrocarbons in Toyotomi, Hokkaido, Japan. 16S rRNA gene sequence-based phylogeny suggested that strain HT-3(T) is a member of the genus Pseudomonas and belongs to the Pseudomonas oleovorans group. Cells of the isolate were Gram-negative, aerobic, straight rods, motile by a single polar flagellum. The strain grew at 4-42 °C, with optimum growth at 35 °C at pH 7, and at pH 6-10. It hydrolysed Tweens 20, 40, 60 and 80, but not casein, gelatin, starch or DNA. Its major isoprenoid quinone was ubiquinone-9 (Q-9) and the DNA G+C content was 65.1 mol%. The whole-cell fatty acid profile consisted mainly of C(16 : 0), C(16 : 1)ω9c and C(18 : 1)ω9c. Phylogenetic analyses based on gyrB, rpoB and rpoD sequences revealed that the isolate could be discriminated from Pseudomonas species that exhibited more than 97 % 16S rRNA gene sequence similarity and phylogenetic neighbours belonging to the P. oleovorans group including the closest relative of the isolate, Pseudomonas alcaliphila. DNA-DNA hybridization with P. alcaliphila AL15-21(T) revealed 51 ± 5 % relatedness. Owing to differences in phenotypic properties and phylogenetic analyses based on multilocus gene sequence analysis and DNA-DNA relatedness data, the isolate merits classification in a novel species, for which the name Pseudomonas toyotomiensis sp. nov. is proposed. The type strain is HT-3(T) ( = JCM 15604(T)  = NCIMB 14511(T)).

Oceanobacillus polygoni sp. nov., a facultatively alkaliphile isolated from indigo fermentation fluid.

A facultatively alkaliphilic, lactic-acid-producing and halophilic strain, designated SA9(T), was isolated from a fermented Polygonum indigo (Polygonum tinctorium Lour.) liquor sample prepared in a laboratory. The 16S rRNA gene sequence phylogeny suggested that strain SA9(T) was a member of the genus Oceanobacillus with the closest relative being Oceanobacillus profundus KCCM 42318(T) (99.3% 16S rRNA gene sequence similarity). Cells of strain SA9(T) stained Gram-positive and were facultative anaerobic straight rods that were motile by peritrichous flagella. The strain grew between 5 and 48 °C (optimum, 35 °C) and at pH 7-12 (optimum, pH 9). The isoprenoid quinone detected was menaquinone-7 (MK-7) and the DNA G+C content was 40.6 ± 0.9 mol%. The whole-cell fatty acid profile mainly consisted of iso-C(15:0), anteiso-C(15:0), C(16:0) and anteiso-C(17:0). DNA-DNA hybridization with Oceanobacillus profundus DSM 18246(T) revealed a DNA-DNA relatedness value of 23 ± 2%. On the basis of the differences in phenotypic and chemotaxonomic characteristics, and the results of phylogenetic analyses based on 16S rRNA gene sequences and DNA-DNA relatedness data from recognized species of the genus Oceanobacillus, strain SA9(T) merits classification as a representative of a novel species of the genus Oceanobacillus, for which the name Oceanobacillus polygoni sp. nov. is proposed. The type strain is SA9(T) ( =JCM 17252(T) =NCIMB 14684(T)). An emended description of the genus Oceanobacillus is also provided.

Psychrobacter piscatorii sp. nov., a psychrotolerant bacterium exhibiting high catalase activity isolated from an oxidative environment

A Gram-negative, non-motile, psychrotolerant bacterium exhibiting high catalase activity, designated strain T-3-2(T), was isolated from a drain of a fish-processing plant. Its catalase activity was 12 000 U (mg protein)(-1), much higher than the activity of the other Psychrobacter strains tested. The strain grew at 0-30 degrees C and in the presence of 0-12 % NaCl. The predominant isoprenoid quinone was ubiquinone-8 (Q-8), and C(16 : 1)omega9c and C(18 : 1)omega9c were the predominant cellular fatty acids. The DNA G+C content of strain T-3-2(T) was 43.9 mol%. 16S rRNA gene sequence phylogeny suggested that strain T-3-2(T) is a member of the genus Psychrobacter, with the closest relatives being the type strains of Psychrobacter nivimaris (99.2 % similarity), P. aquimaris (98.7 %) and P. proteolyticus (98.5 %). DNA-DNA hybridization showed less than 65 % relatedness with these strains. A phylogenetic tree based on gyrB gene sequences was more reliable, with higher bootstrap values than the 16S rRNA gene sequence-based tree. The result also differentiated the isolate from previously reported Psychrobacter species. Owing to the significant differences in phenotypic and chemotaxonomic characteristics and the phylogenetic and DNA-DNA relatedness data, the isolate merits classification within a novel species, for which the name Psychrobacter piscatorii sp. nov. is proposed. The type strain is T-3-2(T) (=JCM 15603(T) =NCIMB 14510(T)).

Amphibacillus indicireducens sp. nov., an alkaliphile that reduces an indigo dye.

Two indigo-reducing alkaliphilic strains, designated strain C40(T) and strain N214, were isolated from a fermented Polygonum Indigo (Polygonum tinctorium Lour.) liquor sample aged for 10 months and obtained from Date City, Hokkaido, Japan. 16S rRNA gene sequence phylogeny suggested that strains C40(T) and N214 were members of the genus Amphibacillus with the closest relative being Amphibacillus xylanus JCM 7361(T) (97.5 % 16S rRNA gene sequence similarity with strain C40(T)), which is the only strain having a 16S rRNA gene sequence similarity higher than 97 % with strain C40(T). Cells of strain C40(T) were Gram-stain-positive, facultatively anaerobic, straight rods that were motile by means of peritrichous flagella. The strains grew between 17 and 39 °C (optimum, 35 °C) and in the pH range of 9.0-12.0. No isoprenoid quinone was detected and the DNA G+C content was 37.5-37.7 mol%. The whole-cell fatty acid profile mainly consisted of iso-C(15 : 0) and anteiso-C(15 : 0). DNA-DNA hybridization of strain C40(T) with Amphibacillus xylanus JCM 7361(T) revealed a DNA-DNA relatedness value of 10±3 %. Owing to the differences in phenotypic characteristics and phylogenetic analyses based on 16S rRNA gene sequences, as well as DNA-DNA relatedness data from reported species of the genus Amphibacillus, the isolates merit classification as a novel species in the genus Amphibacillus, for which the name Amphibacillus indicireducens sp. nov. is proposed. The type strain is C40(T) ( = JCM 17250(T) = NCIMB 14686(T)). An additional strain of the species is N214. An emended description of the genus Amphibacillus is provided.

Temperature and nutrient availability control growth rate and fatty acid composition of facultatively psychrophilic Cobetia marina strain L-2

A facultative psychrophilic bacterium, strain L-2, that grows at 0 and 5°C as minimum growth temperatures in complex and defined media, respectively, was isolated. On the basis of taxonomic studies, strain L-2 was identified as Cobetia marina. The adaptability of strain L-2 to cold temperature was higher than that of the type strain and of other reported strains of the same species. When the bacterium was grown at 5–15°C in a defined medium, it produced a high amount of trans-unsaturated fatty acids. By contrast, in a complex medium in the same temperature range it produced a low amount of trans-unsaturated fatty acids. In the complex medium at 5°C, the bacterium exhibited a three-fold higher growth rate than that obtained in the defined medium. Following a temperature shift from 11 to 5°C, strain L-2 grew better in complex than in defined medium. Furthermore, when the growth temperature was shifted from 0 to 5°C both the growth rate and the yield of strain L-2 growing in complex medium was markedly enhanced. These phenomena suggest that an upshift of the growth temperature had a positive effect on metabolism. The effects of adding complex medium components to the defined medium on bacterial growth rate and fatty acid composition at 5°C were also studied. The addition of yeast extract followed by peptone was effective in promoting rapid growth, while glutamate addition was less effective, resulting in a cis-unsaturated fatty acid ratio similar to that of cells grown in the complex medium. These results suggest that the rapid growth of strain L-2 at low temperatures requires a high content of various amino acids rather than the presence of a high ratio of cis-unsaturated fatty acids in the cell membrane.

Amphibacillus iburiensis sp. nov., an alkaliphile that reduces an indigo dye.

An indigo-reducing alkaliphilic strain, designated strain N314(T), was isolated from a fermented polygonum indigo (Polygonum tinctorium Lour.) liquor sample, aged for 10 months, that was obtained from Date City, Iburi Branch, Hokkaido, Japan. The 16S rRNA gene sequence phylogeny suggested that strain N314(T) is a member of the genus Amphibacillus, with the closest relatives being Amphibacillus indicireducens (98.9 % similarity to the type strain) and Amphibacillus xylanus (98.0 % similarity to the type strain), the only species with 16S rRNA gene sequence similarities higher than 97 % to strain N314(T). The cells of the isolate stained Gram-positive and were facultatively anaerobic, straight rods that were motile by means of peritrichous flagella. The strain grew at 26-39 °C with optimum growth at 36 °C. It grew at pH 8.0-9.1, with optimum growth at pH 8.9-9.1. No isoprenoid quinone was detected, and the DNA G+C content was 38.4 mol%. The whole-cell fatty acid profile consisted mainly of iso-C15 : 0 and anteiso-C15 : 0. Analysis of DNA-DNA hybridization with the type strains of A. indicireducens and A. xylanus revealed 29±2 % and 10±2 % relatedness, respectively. Owing to differences in phenotypic characteristics from reported species of the genus A. and results of phylogenetic analyses based on 16S rRNA gene sequences and DNA-DNA relatedness data, the isolate merits classification within a novel species, for which the name Amphibacillus iburiensis sp. nov. is proposed. The type strain is N314(T) ( = JCM 18529(T) = NCIMB 14823(T)).

Brevibacillus nitrificans sp. nov., a nitrifying bacterium isolated from a microbiological agent for enhancing microbial digestion in sewage treatment tanks.

A heterotrophic nitrifying bacterium, designated strain DA2(T), was isolated from a microbiological agent for enhancing microbial digestion in sewage treatment tanks. Cells of strain DA2(T) were Gram-positive, facultatively anaerobic, sporulating rods that were motile by means of peritrichous flagella; they were able to grow at pH 5-8. The major isoprenoid quinone of strain DA2(T) was menaquinone-7 (MK-7) and its cellular fatty acid profile consisted mainly of iso-C(15 : 0) (18.6 %) and anteiso-C(15 : 0) (69.1 %). The DNA G+C content was 54.1 mol%. 16S rRNA gene sequence phylogeny suggested that strain DA2(T) is a member of the genus Brevibacillus, with highest sequence similarities (in parentheses) to the type strains of Brevibacillus choshinensis (99.7 %), B. formosus (99.4 %), B. brevis (99.4 %), B. agri (99.0 %), B. reuszeri (98.8 %), B. parabrevis (98.7 %), B. centrosporus (98.6 %), B. limnophilus (97.4 %), B. panacihumi (97.3 %) and B. invocatus (97.3 %). DNA-DNA hybridization showed less than 60 % relatedness between strain DA2(T) and type strains of the most closely related species given above. Given the significant differences in phenotypic and chemotaxonomic characteristics, and phylogenetic analysis based on the 16S rRNA sequence and DNA-DNA relatedness data, the isolate merits classification as a novel species, for which the name Brevibacillus nitrificans is proposed; the type strain of this species is DA2(T) (= JCM 15774(T) = NCIMB 14531(T)).