Rhodanobacter rhizosphaerae sp. nov., isolated from soil of ginseng rhizosphere.

A Gram-stain-negative, aerobic, non-motile, non-spore-forming, yellow and rod-shaped bacterium, designated strain CR164T, was isolated from the rhizosphere soil of a ginseng field at Geumsan in Korea. CR164T grew at between 15 and 37 °C (optimal growth at 28 °C), between pH 6.0 and 9.0 (optimal growth at pH 7.0) and at salinities of 0-1.0 % (w/v) NaCl, growing optimally in the absence of NaCl. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that CR164T represents a member of the genus Rhodanobacter, showing the highest sequence similarity to Rhodanobactercaeni MJ01T (98.5 %), Rhodanobacter ginsenosidimutans Gsoil 3054T (98.4 %), Rhodanobacter thiooxydans LCS2T (98.3 %), Rhodanobacter lindaniclasticus RP5557T (98.1 %), Rhodanobacter denitrificans 2APBS1T (98.0 %), Rhodanobacter fulvus Jip2T (97.6 %), Rhodanobacter soli DCY45T (97.3 %) and 'Rhodanobacterxiangquanii' BJQ-6 (97.0 %). The major fatty acids were iso-C17 : 1ω9c (21.8 %), iso-C15 : 0 (12.1 %), iso-C11 : 0 (11.9 %) and iso-C16 : 0 (11.1 %). The predominant ubiquinone was Q-8. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The G+C content of the genomic DNA was 62.3 mol%. DNA-DNA relatedness between CR164T and the type strains of eight other species of the genus ranged from 51 to 9 %. On the basis of the polyphasic analysis, CR164T represents a novel species of the genus Rhodanobacter, for which the name Rhodanobacter rhizosphaerae sp. nov. is proposed. The type strain is CR164T (=KACC 18699T=NBRC 111845T).

Terrimonas rhizosphaerae sp. nov., isolated from ginseng rhizosphere soil.

The novel isolate belonging to the genus Terrimonas, designated CR94T, was isolated from rhizosphere soil of a ginseng field in Geumsan, Korea. Cells of strain CR94T were strictly aerobic, Gram-stain-negative, non-motile, non-filamentous single rods. Growth was observed at 10-37 °C (optimum 28 °C) and at pH 4.0-10.0 (optimum pH 6.0). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain CR94T belonged to the genus Terrimonas, showing highest sequence similarity to Terrimonas lutea DYT (97.3 %), Terrimonas pekingensis QHT (97.1 %), Terrimonas aquatica RIB1-6T (95.6 %), Terrimonas rubra M-8T (94.7 %) and Terrimonas ferruginea ATCC 13524T (93.8 %). DNA-DNA relatedness values between strain CR94T and T. lutea KACC 13047T, T. pekingensis KACC 18795T, T. ferruginea KACC 11310T and T. aquatica LMG 24825T were 30.5, 28.9, 17.8 and 13.5 %, respectively. The DNA G+C content was 46.5 mol% and the major respiratory quinone was menaquinone-7 (MK-7). The major cellular fatty acids of strain CR94T were iso-C15:1 G and iso-C15 : 0. On the basis of the polyphasic analysis, strain CR94T represents a novel species of the genus Terrimonas, for which the name Terrimonas rhizosphaerae sp. nov. is proposed. The type strain is CR94T (=KACC 17564T=NCAIM B 025317T).

Streptomyces panaciradicis sp. nov., a ß-glucosidase-producing bacterium isolated from ginseng rhizoplane.

A Gram-staining-positive actinobacterium, designated strain 1MR-8(T), was isolated from the rhizoplane of ginseng and its taxonomic status was determined using a polyphasic approach. The isolate formed long chains of spores that were straight, cylindrical and smooth-surfaced. Strain 1MR-8(T) grew at 10-37 °C (optimum 28 °C), whilst no growth was observed at 45 °C. The pH range for growth was 4.0-11.0 (optimum pH 6.0-8.0) and the NaCl range for growth was 0-7% (w/v) with optimum growth at 1% (w/v). Strain 1MR-8(T) had cell-wall peptidoglycans based on ll-diaminopimelic acid. Glucose, mannose and ribose were the whole-cell sugars. The predominant isoprenoid quinones were MK-9 (H4), MK-9 (H6) and MK-9 (H8) and the major fatty acids were anteiso-C(15:0), iso-C(15:0), anteiso-C(17:0) and iso-C(16:0). 16S rRNA gene sequencing studies showed that the novel strain was closely related to the type strains of Streptomyces caeruleatus GIMN4(T), Streptomyces curacoi NRRL B-2901(T), Streptomyces capoamus JCM 4734(T) and Streptomyces coeruleorubidus NBRC 12761(T) with similarities of 98.8%. However, DNA-DNA relatedness, as well as physiological and biochemical analyses, showed that strain 1MR-8(T) could be differentiated from its closest phylogenetic relatives. It is proposed that this strain should be classified as a representative of a novel species of the genus Streptomyces, with the suggested name Streptomyces panaciradicis sp. nov. The type strain is 1MR-8(T) ( = KACC 17632(T) = NBRC 109811(T)).

Chitinophaga ginsengihumi sp. nov., isolated from soil of ginseng rhizosphere.

A novel strain designated SR18(T) was isolated from the rhizosphere soil of a ginseng in Korea. Cells were Gram-staining-negative, motile by gliding, catalase-positive and oxidase-negative, non-spore-forming rods. The isolate grew aerobically at 15-45 °C (optimum 28 °C), pH 5.5-7.5 (optimum pH 7.0) and with 0-3.0% (w/v) NaCl (optimum 1.5% NaCl). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SR18(T) belongs to the genus Chitinophaga with sequence similarity of 97.2% and 97.0% to Chitinophaga japonensis 758(T) and Chitinophaga rupis CS5-B1(T), respectively. Similarity to other species of the genus Chitinophaga was 92.8-95.5%. The predominant menaquinone was MK-7. Major fatty acids were iso-C(15 : 0) and C(16 : 1)ω5c. The polar lipids included phosphatidylethanolamine, unidentified phospholipids, unknown aminolipids and unknown lipids. The genomic DNA G+C content was 45.3 mol%. DNA-DNA relatedness between strain SR18(T) and C. japonensis NBRC 16041(T) was 29-32%. On the basis of polyphasic analysis from this study, strain SR18(T) represents a novel species of the genus Chitinophaga, for which the name Chitinophaga ginsengihumi sp. nov. is proposed. The type strain is SR18(T) ( = KACC 17604(T) = NBRC 109832(T)).

Terriglobus tenax sp. nov., an exopolysaccharide-producing acidobacterium isolated from rhizosphere soil of a medicinal plant.

An exopolysaccharide-producing bacterium, designated strain DRP 35(T), was isolated from the rhizosphere soil of a medicinal herb, Angelica sinensis, at Geumsan in Korea. Cells were Gram-staining-negative, non-motile, catalase-positive and oxidase-negative short rods. The isolate grew aerobically from 15 to 45 °C (optimum 30 °C), pH 3.5-7.0 (optimum pH 5.0) and in the presence of 0-1.0% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain DRP 35(T) belongs to the genus Terriglobus in the phylum Acidobacteria with a sequence similarity of 97.2% and 97.0% to Terriglobus saanensis SP1PR4(T) and Terriglobus roseus KBS63(T), respectively. The genomic DNA G+C content was 62.1 mol%. DNA-DNA relatedness between strain DRP 35(T) and the type strains of the other species of the genus Terriglobus, T. saanensis SP1PR4(T) and T. roseus KBS63(T), were 24.6 and 17.2%, respectively. The predominant menaquinone was MK-8. Major fatty acids were iso-C(15 : 0), C(16 : 1)ω7c and C(16 : 0). The polar lipids were phosphatidylethanolamine, unidentified aminophospholipid and unknown phospholipids. On the basis of polyphasic analysis from this study, strain DRP 35(T) represents a novel species of the genus Terriglobus for which the name Terriglobus tenax sp. nov. is proposed. The type strain is DRP 35(T) ( = KACC 16474(T) = NBRC 109677(T)).

Purification, characterization, and properties of an alkaline protease produced by Serratia marcescens S3-R1 inhabiting Korean ginseng rhizosphere.

BACKGROUND: An alkaline protease produced by the Serratia marcescens S3-R1 which inhabits in the Korean ginseng rhizosphere was investigated. The purposes of this study were to characterize and purify the bacterial enzyme by four different purification steps: precipitation of enzyme fraction by ammonium sulfate, loading the enzyme pellets on a DEAE-Sepharose anion-exchange chromatograph, separation of the fraction containing enzyme activity by fast protein liquid Mono Q chromatography and identification of the single-band fraction by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and then quantification of the single-band fraction by reverse-phase high-performance liquid chromatography. RESULTS: The molecular weight of the purified protease was estimated as 50 308 Da by matrix-assisted laser desorption ionization time-of-flight analysis. The N-terminal amino acid sequence of the protease was identified as Ala-Val-Thr-Ile-Glu-Asp-Ala-Val-Asp-Asp, and the enzyme belongs to the metalloprotease family. The optimal activities of the protease occurred at pH 7-9 and a temperature 40 °C. The ranges of pH and thermal stability of the enzyme were at 7-10 and 30-40 °C, respectively. CONCLUSION: The alkaline protease was successfully purified and characterized from the bacterium Serratia marcescens S3-R1, which has potential for industrial application, including milk protein hydrolysates.

Mucilaginibacter herbaticus sp. nov., isolated from the rhizosphere of the medicinal plant Angelica sinensis.

A strictly aerobic, Gram-staining-negative, non-motile and rod-shaped bacterial strain, DR-9(T), was isolated from rhizosphere soil of the medicinal herb Angelica sinensis. Strain DR-9(T) grew at 20-40 °C, at pH 4.0-9.0 and in the presence of 0-1 % (w/v) NaCl. The major fatty acids were iso-C15 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c and/or iso-C15 : 0 2-OH), MK-7 was the major isoprenoid quinone, and phosphatidylethanolamine and an unidentified aminophospholipid were the major polar lipids. A phylogenetic tree based on 16S rRNA gene sequences showed that strain DR-9(T) formed a lineage within the genus Mucilaginibacter and was closely related to Mucilaginibacter polysacchareus DRP28(T) (96.1 % sequence similarity), Mucilaginibacter myungsuensis HMD1056(T) (95.9 % sequence similarity), Mucilaginibacter ximonensis XM-003(T) (95.8 %) and Mucilaginibacter boryungensis BDR-9(T) (95.1 %). The status of strain DR-9(T) as a representative of a separate species was confirmed by DNA hybridization, with 38.6, 36.3 and 29.9 % DNA-DNA relatedness with M. polysacchareus DRP28(T), M. ximonensis XM-003(T) and M. boryungensis BDR-9(T), respectively. The genomic DNA G+C content of strain DR-9(T) was 49.8 %. These data suggest that strain DR-9(T) should be considered as a representative of a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter herbaticus sp. nov. is proposed. The type strain is DR-9(T) ( = KACC 16469(T) = NBRC 108839(T)).

Soybean oil-degrading bacterial cultures as a potential for control of green peach aphids (Myzus persicae).

Microorganisms capable of degrading crude oil were isolated and grown in soybean oil as a sole carbon source. The microbial cultures were used to control green peach aphids in vitro. Approximately 60% mortality of aphids was observed when the cultures were applied alone onto aphids. To examine the cultures as a pesticide formulation mixture, the cultures were combined with a low dose of the insecticide imidacloprid (one-fourth dose of recommended field-application rate) and applied onto aphids. The cultures enhanced significantly the insecticidal effectiveness of imidacloprid, which was higher than imidacloprid alone applied at the low dose. The isolated microorganisms exhibited high emulsifying index values and decreased surface tension values after being grown in soybean oil media. GC/MS analyses showed that microorganisms degraded soybean oil to fatty acids. The cultures were suggested to play the roles of wetting, spreading, and sticking agents to improve the effectiveness of imidacloprid. This is the first report on the control of aphids by using oil-degrading microbial cultures.