Taxonomic identification, phenol biodegradation and soil remediation of the strain Rhodococcus sacchari sp. nov. Z13T.

Phenols are highly toxic chemicals that are extensively used in industry and produce large amounts of emissions. Notably, phenols released into the soil are highly persistent, causing long-term harm to human health and the environment. In this study, a gram-positive, aerobic, and rod-shaped bacterial strain, Z13T, with efficient phenol degradation ability, was isolated from the soil of sugarcane fields. Based on the physiological properties and genomic features, strain Z13T is considered as a novel species of the genus Rhodococcus, for which the name Rhodococcus sacchari sp. nov. is proposed. The type strain is Z13T (= CCTCC AB 2022327T = JCM 35797T). This strain can use phenol as its sole carbon source. Z13T was able to completely degrade 1200 mg/L phenol within 20 h; the maximum specific growth rate was µmax = 0.93174 h-1, and the maximum specific degradation rate was qmax = 0.47405 h-1. Based on whole-genome sequencing and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, strain Z13T contains a series of phenol degradation genes, including dmpP, CatA, dmpB, pcaG, and pcaH, and can metabolize aromatic compounds. Moreover, the potential of strain Z13T for soil remediation was investigated by introducing Z13T into simulated phenol-contaminated soil, and the soil microbial diversity was analyzed. The results showed that 100% of the phenol in the soil was removed within 7.5 d. Furthermore, microbial diversity analysis revealed an increase in the relative species richness of Oceanobacillus, Chungangia, and Bacillus.

Fumigaclavine C ameliorates liver steatosis by attenuating hepatic de novo lipogenesis via modulation of the RhoA/ROCK signaling pathway.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) has been well defined as a common chronic liver metabolism disorder. Statins as a first-line therapeutic treatment had some side effects. Here, we found that Fumigaclavine C (FC) was collected from endophytic Aspergillus terreus via the root of Rhizophora stylosa (Rhizophoraceae), had potential anti-adipogenic and hepatoprotective effects both in vitro and in vivo without obvious adverse side effects. However, the mechanisms of the prevention and management of FC for hepatic steatosis are incompletely delineated. METHODS: The pharmacodynamic effects of FC were measured in high-fat diet (HFD)-induced obese mice. Liver index and blood biochemical were examined. Histopathological examination in the liver was performed by hematoxylin & eosin or oil red O. The levels of serum TG, TC, LDL-c, HDL-c, FFA, T-bili, ALT, AST, creatinine, and creatine kinase were estimated via diagnostic assay kits. The levels of hepatic lipid metabolism-related genes were detected via qRT-PCR. The expression levels of hepatic de novo lipogenesis were quantitated with Western blot analysis.  RESULTS: FC-treatment markedly reduced hepatic lipid accumulation in HFD-induced obese mice. FC significantly attenuated the hepatic lipid metabolism and ameliorated liver injury without obvious adverse side effects. Moreover, FC also could dose-dependently modulate the expressions of lipid metabolism-related transcription genes. Mechanically, FC notably suppressed sterol response element binding protein-1c mediated de novo lipogenesis via interfering with the RhoA/ROCK signaling pathway by decreasing the levels of geranylgeranyl diphosphate and farnesyl diphosphate. CONCLUSIONS: These findings suggested that FC could improve hepatic steatosis through inhibiting de novo lipogenesis via modulating the RhoA/ROCK signaling pathway.

Metabolome analysis of the response and tolerance mechanisms of Saccharomyces cerevisiae to formic acid stress.

Various inhibitors are produced during the hydrolysis of lignocellulosic biomass that can interfere with the growth of yeast cells and the production of bioethanol. Formic acid is a common weak acid inhibitor present in lignocellulosic hydrolysate that has toxic effects on yeast cells. However, the mechanism of the response of Saccharomyces cerevisiae to formic acid is not fully understood. In this study, liquid chromatography-mass spectrometry (LC-MS) was used to investigate the effects of formic acid treatment on cell metabolites of S. cerevisiae. Treatment with different concentrations of formic acid significantly inhibited the growth of yeast cells, reduced the yield of ethanol, prolonged the cell fermentation cycle, and increased the content of malondialdehyde. Principal component analysis and orthogonal partial least squares discriminant analysis showed that 55 metabolites were significantly altered in S. cerevisiae after formic acid treatment. The metabolic relevance of these compounds in the response of S. cerevisiae to formic acid stress was investigated. Formic acid can cause oxidative stress, inhibit protein synthesis, and damage DNA in S. cerevisiae, and these are possible reasons for the inhibition of S. cerevisiae cell growth. In addition, the levels of several aromatic amino acids identified in the cells of formic acid-treated yeast were increased; the biosynthesis of nucleotides was slowed, and energy consumption was reduced. These mechanisms may help to improve the tolerance of yeast cells to formic acid. The results described herein highlight our current understanding of the molecular mechanism of the response of S. cerevisiae to formic acid. The study will provide a theoretical basis for research on the tolerance mechanisms of S. cerevisiae.

Transcriptomic analysis of formic acid stress response in Saccharomyces cerevisiae.

Formic acid is a representative small molecule acid in lignocellulosic hydrolysate that can inhibit the growth of Saccharomyces cerevisiae cells during alcohol fermentation. However, the mechanism of formic acid cytotoxicity remains largely unknown. In this study, RNA-Seq technology was used to study the response of S. cerevisiae to formic acid stress at the transcriptional level. Scanning electron microscopy and Fourier transform infrared spectroscopy were conducted to observe the surface morphology of yeast cells. A total of 1504 genes were identified as being differentially expressed, with 797 upregulated and 707 downregulated genes. Transcriptomic analysis showed that most genes related to glycolysis, glycogen synthesis, protein degradation, the cell cycle, the MAPK signaling pathway, and redox regulation were significantly induced under formic acid stress and were involved in protein translation and synthesis amino acid synthesis genes were significantly suppressed. Formic acid stress can induce oxidative stress, inhibit protein biosynthesis, cause cells to undergo autophagy, and activate the intracellular metabolic pathways of energy production. The increase of glycogen and the decrease of energy consumption metabolism may be important in the adaptation of S. cerevisiae to formic acid. In addition, formic acid can also induce sexual reproduction and spore formation. This study through transcriptome analysis has preliminarily reveal the molecular response mechanism of S. cerevisiae to formic acid stress and has provided a basis for further research on methods used to improve the tolerance to cell inhibitors in lignocellulose hydrolysate.

High-expression keratinase by Bacillus subtilis SCK6 for enzymatic dehairing of goatskins.

An extracellular keratinase gene from Bacillus sp. LCB12, isolated from saline-alkali soil, was cloned and high-effectively expressed in Bacillus subtilis SCK6. The enzyme was purified by ammonium sulphate precipitation and cation-exchange chromatography. Its molecular mass was estimated to be 30.95 kDa by SDS-PAGE. The optimum conditions for catalytic activity of the enzyme were pH 10.0 and 60 °C. The enzyme activity was completely inhibited by PMSF, while it was slightly inhibited by EDTA. Moreover, the surfactants Tween 20, Tween 80 and Triton X-100, showed little effect on enzyme activity respectively. The crude enzyme was used as an alternative to sodium sulfide for dehairing of goat skins. The goatskin was dehaired by the enzyme at 33-35 °C in 6 h. The enzymatic dehaired pelt showed better general appearance and better whiteness by visual tests, and the grain surface of enzymatic dehaired pelt revealed absence of hair shaft with empty follicles by stereoscopic observation. Meanwhile, the epidermis was completely removed and the collagen fiber structure of enzymatic dehaired pelt was more opened, regular and even in dermis comparing with conventional dehaired pelt by histological analysis.

Glycine betaine enhances biodegradation of phenol in high saline environments by the halophilic strain Oceanobacillus sp. PT-20.

The halophilic bacterial strain PT-20, isolated from saline alkali soil samples and identified as a member of the genus Oceanobacillus, exhibited a robust ability to degrade phenol under high salt conditions. It was determined that strain PT-20 was capable of degrading 1000 mg L-1 phenol completely in the presence of 10% NaCl within 120 h. Under the optimal degradation conditions, pH 8.0, 3% NaCl and 30 °C, 1000 mg L-1 phenol could be completely degraded in 48 h. Interestingly, the biodegradation rate of phenol was dramatically improved in the presence of glycine betaine. When glycine betaine was added, the time required to degrade 1000 mg L-1 phenol completely was significantly reduced from 120 h to 72 h, and the corresponding average degradation rate increased from 8.43 to 14.28 mg L-1 h-1 with 10% NaCl. Furthermore, transcriptome analysis was performed to investigate the effects of phenol and glycine betaine on the transcriptional levels of strain PT-20. The results indicated that the addition of glycine betaine enhanced the resistance of cells to phenol, increased the growth rate of strain PT-20 and upregulated the expression of related enzyme genes. In addition, the results of enzyme activity assays indicated that strain PT-20 degraded phenol mainly through a meta-fission pathway.

Enhanced extracellular recombinant keratinase activity in Bacillus subtilis SCK6 through signal peptide optimization and site-directed mutagenesis.

Keratinase has a great commercial value owing to its applications in the enzymatic dehairing of goatskins. In this study, we adopted a combined strategy to enhance the extracellular recombinant keratinase activity in Bacillus subtilis SCK6. First, nine signal peptides were screened to enhance the expression of extracellular keratinase. The recombinant strain with SPLipA exhibited the highest extracellular keratinase activity of 739.03 U per mL, which was two-fold higher activity of the wild type. Second, based on the multiple sequence alignment with the bacterial alkaline proteases, the mutant (M123L/V149I/A242N) was introduced into the keratinase. Comparing with the wild type of keratinase, the mutant M123L/V149I/A242N showed an increase in the extracellular keratinase activity, which was about 1.2-fold higher activity of the wild type. Finally, the keratinase expression vector with SPLipA and mutant M123L/V149I/A242N was constructed, and the extracellular keratinase activity reported at 830.91 U per mL was a 2.2-fold activity of the wild type. Then, the mutant keratinase was purified and characterized. The mutant exhibited properties similar to those of the wild type at an optimal temperature of 60 °C and pH 10.0. Conclusively, the extracellular expression of keratinase was enhanced via a combined strategy, and the mutant keratinase demonstrated properties similar to that of the wild type of keratinase.

Streptomyces geranii sp. nov., a novel endophytic actinobacterium isolated from root of Geranium carolinianum L.

A novel endophytic actinomycete, designated A301T, was isolated from the root of Geranium carolinianum Linn collected from Mount Emei in China and characterized using a polyphasic approach. Growth occurred at 10-37 °C, pH 6-11 and in the presence of 0-5 % NaCl (w/v). Strain A301T contained ll-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The whole-cell hydrolysates included galactose and ribose. The predominant menaquinones were MK-9(H6) and MK-9(H8). The major cellular fatty acids were C15 : 0, C16 :  0, anteiso-C15 : 0 and iso-C16 : 0. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, two unidentified phospholipids, three unidentified lipids and two unidentified aminophospholipids. Strain A301T shared the highest 16S rRNA gene sequence similarity to Streptomyces cinereorubersubsp. fructofermentans NBRC 15396T (98.1 %) and Streptomyces turgidiscabies ATCC 700248T (98.1 %). The DNA-DNA relatedness values between strain A301T and the two above-mentioned members of the genus Streptomyces were 42.6 % and 47.2 %, respectively. The G+C content of the DNA was 70.5 mol%. On the basis of the polyphasic approach and DNA-DNA hybridization data, strain A301T represents a novel species within the genus Streptomyces, for which the name Streptomyces geranii sp. nov. is proposed. The type strain is A301T (=CGMCC 4.7422T=JCM 32177T).

Streptomyces populi sp. nov., a novel endophytic actinobacterium isolated from stem of Populus adenopoda Maxim.

A novel endophytic actinobacterium strain, designated A249T, was isolated from the stem of Populus adenopoda collected at Mount Qingcheng in south-west China. Its taxonomic position was determined by using a polyphasic approach. The cultural and morphological characteristics of isolate A249T were consistent with members of the genus Streptomyces. Growth occurred at 10-37 °C, pH 6.0-12.0 and in the presence of 0-4 % (w/v) NaCl. Analysis of the 16S rRNA gene sequence and phylogenetic trees showed the closest phylogenetic relatives to strain A249T were Streptomyces shaanxiensis JCM 16925T (98.0 % 16S rRNA gene sequence similarity) and Streptomyces lanatus JCM 4332T (97.9 %). The DNA-DNA hybridization values between the strain A249T and the two reference strains ranged from 41.4 to 49.4 %. The DNA G+C content was 71.7 mol%. The range of average nucleotide identity values was 81.5-86.7 %. Chemical analysis of cellular components indicated that strain A249T contained ll-diaminopimelic acid, xylose and galactose. The predominant menaquinones were MK-9(H6) and MK-9(H8). The polar lipids were diphosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylethanolamine, two unidentified lipids, one unidentified phospholipid, one unidentified aminolipid and one unidentified aminophospholipid. The major fatty acids comprised C16 : 0, iso-C14 : 0, iso-C15 : 0, iso-C16 : 0, anteiso-C15 : 0 and C16 : 1ω7c. On the basis of the phenotypic and genotypic differentiation of the three tested strains, isolate A249T is proposed to represent a novel species of the genus Streptomyces, named Streptomyces populi sp. nov. The type strain is A249T (=CGMCC 4.7417T=JCM 32175T).

Halomonas saliphila sp. nov., a moderately halophilic bacterium isolated from a saline soil.

A novel, Gram-stain-negative, aerobic, rod-shaped, motile and moderately halophilic bacterium, designated strain LCB169T, was isolated from a saline soil sample from Gansu Province, PR China. The cells of LCB169T grew at 10-52 °C (optimum 30 °C), at pH 6.0-10.0 (optimum pH 8.0) and in the presence of 0-17 % (w/v) NaCl (optimum 10-15 %). Phylogenetic analysis based on 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD genes sequences revealed that LCB169T represented a member of the genus Halomonas in the class Gammaproteobacteria. The most closely related species were Halomonas daqingensis DQD2-30T (98.0 % 16S rRNA gene sequence similarity), Halomonas kenyensis AIR-2T (97.8 %) and Halomonas desiderata FB2T (97.5 %). DNA-DNA relatedness values between LCB169T and H. daqingensis CGMCC 1.6443T, H. desiderata DSM 9502T and H. kenyensis DSM 17331T were 33, 35 and 38 %, respectively. The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and three unidentified phospholipids. The major fatty acids were C18 : 1ω7c, C16 : 0, C16 : 1ω7c and C12 : 0 3-OH. The genomic DNA G+C content was 66.1 mol% and the predominant respiratory quinone was Q-9. On the basis of the results of phenotypic, phylogenetic and chemotaxonomic analyses and DNA-DNA hybridization relatedness values, LCB169T is considered to represent a novel species of the genus Halomonas, for which the name Halomonas saliphila sp. nov. is proposed. The type strain is LCB169T (=CGMCC 1.15818T=KCTC 52618T).

Screening cyhalothrin degradation strains from locust epiphytic bacteria and studying Paracoccus acridae SCU-M53 cyhalothrin degradation process.

All locust epiphytic bacteria were screened and a total of 62 epiphytic bacteria were obtained from samples of Acrida cinerea. Via phylogenetic analysis, the 62 epiphytic bacteria were allocated to 27 genera, 18 families, 13 orders, six classes, and four phylums. Then, cyhalothrin degradation experiments were conducted, and the 10 strains that degraded more than 30% cyhalothrin and Paracoccus acridae SCU-M53 showed the highest cyhalothrin degradation rate of 70.5%. Furthermore, Paracoccus acridae SCU-M53 was selected for optimal cyhalothrin biodegradation conditions via the response surface method (Design-Expert). Under the optimum conditions (28 °C, 75 mg/L, and 180 rpm), the cyhalothrin degradation rate reached 79.84% after 2 days. This suggests the possibility that isolating biodegradation cyhalothrin strains from Acrida cinerea is feasible.

Ornithinibacillus salinisoli sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.

A taxonomic study was performed on strain LCB256T, which was isolated from a saline-alkali soil sample taken from northwestern China. Cells of strain LCB256T were Gram-stain-positive, aerobic, rod-shaped and grew at 3-17 % (w/v) NaCl (optimum 10-15 %), 10-52 °C (optimum 25-30 °C) and pH 7.0-9.0 (optimum 8.0). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LCB256T was most closely related to the two genera of Ornithinibacillus and Oceanobacillus, showing highest sequence similarity to Oceanobacillus limi KCTC 13823T (97.8 %) and Ornithinibacillus bavariensis WSBC 24001T (97.2 %). The peptidoglycan amino acid type was found to be A4ß and the major respiratory quinone was determined to be MK-7. The polar lipid profile of strain LCB256T contained diphosphatidylglycerol, phosphatidylglycerol, one unidentified phospholipid and two unidentified aminolipids. The dominant cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The G+C content of genomic DNA was 39.3 mol%. DNA-DNA relatedness values between strain LCB256T and Ornithinibacillus halophilus KCTC 13822T and Oceanobacillus limi KCTC 13823T were 46.2 and 34.8 %, respectively. Based on this polyphasic taxonomic study, a novel species of the genus Ornithinibacillus, Ornithinibacillussalinisoli sp. nov. is proposed. The type strain is LCB256T (=CGMCC 1.15809T=KCTC 33862T).

Planococcus salinus sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.

A novel aerobic, Gram-stain-positive, motile, moderately halophilic and coccoid bacterial strain, designated LCB217T, was isolated from a saline-alkali soil in north-western China and identified using a polyphasic taxonomic approach. Growth occurred with 3-15 % (w/v) NaCl (optimum 3-5 %), at 10-45 °C (optimum 30 °C) and at pH 7.0-9.0 (optimum pH 9.0). Strain LCB217T contained MK-7 and MK-8 as the predominant menaquinones and anteiso-C15 : 0, iso-C14 : 0 and iso-C16 : 0 as the major fatty acids. The polar lipids from strain LCB217T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unidentified phospholipid, one unidentified aminophospholipid and one unidentified lipid. The peptidoglycan type was A4α (l-Lys-d-Glu). Phylogenetic analysis of the 16S rRNA gene sequence showed that strain LCB217T belonged to the genus Planococcus and was closely related to the type strains Planococcus plakortidis AS/ASP6 (II)T (98.2 % similarity), Planococcus maitriensis S1T (97.7 %) and Planococcus salinarum ISL-16T (97.2 %). The G+C content of the genomic DNA was 49.4 mol%. DNA-DNA relatedness values between strain LCB217T andPlanococcusplakortidis AS/ASP6 (II)T, Planococcusmaitriensis S1T andPlanococcussalinarum ISL-16T were 29.5, 38.1 and 39.5 %, respectively. On the basis of the phenotypic, phylogenetic and genomic data, strain LCB217T represents a novel species of the genus Planococcus, for which the name Planococcus salinus sp. nov. is proposed. The type strain is LCB217T (=CGMCC 1.15685T=KCTC 33861T).

Adaptations of Bacillus shacheensis HNA-14 required for long-term survival under osmotic challenge: a multi-omics perspective.

Genomic sequence, transcriptomic, metabolomic and fatty acid analyses of strain HNA-14 were performed to understand the mechanism of salt tolerance for long-term survival. The results indicated that strain HNA-14 has different osmotic resistance mechanisms for long-term survival and short-term salt stress. The cells mainly synthesized compatible solutes to resist osmotic pressure when cultured under nutrient deficient conditions, while they can slow down the synthesis rate and uptake from the environment when cultured under a nutritionally rich environment. Also, the amounts of branched and unsaturated fatty acids in the cell membrane are maintained to a high degree (>50%) to maintain the fluidity of the cell membrane; when the cells are cultured in a high osmotic environment for long-term survival, they may increase the content of branched fatty acids and phosphoric fatty acids to increase the fluidity of the cell membrane to resist the high osmotic pressure.

Paracoccusacridae sp. nov., isolated from the insect Acrida cinerea living in deserted cropland.

A Gram-stain-negative, aerobic, rod-shaped, non-motile bacterial strain, designated SCU-M53T, was isolated from the insect Acrida cinerea. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that strain SCU-M53T belonged to the genus Paracoccus, having Paracoccus chinensisNBRC 104937T (97.04 % 16S rRNA gene sequence similarity) and Paracoccus niistensis KCTC 22789T (96.70 %) as the most closely related phylogenetic neighbours. Growth occurred at 10-40 °C (optimum 25-30 °C), pH 5.0-10.0 (optimum pH 6.5-7.5) and with 0-4 % (w/v) NaCl (optimum 0-1 % NaCl). The fatty acids of strain SCU-M53T were C18 : 1ω7c, C18 : 0, C16 : 0, C14 : 0 3-OH, C14 : 0 and C10 : 0 3-OH. The polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, an unknown aminolipid, two unknown phospholipids and two unknown lipids. The isoprenoid quinone was ubiquinone-10. The DNA G+C content was 60.6 mol%. Strain SCU-M53T exhibited 36.5 and 28.6 % DNA-DNA relatedness to P. chinensis NBRC 104937T and P. niistensis KCTC 22789T, respectively. According to these results, strain SCU-M53T represents a novel species of the genus Paracoccus, for which the name Paracoccus acridae sp. nov. is proposed. The type strain is SCU-M53T (=KCTC 42932T=CGMCC 1.15419T).

Comparative analysis of chemical constituents, antimicrobial and antioxidant activities of ethylacetate extracts of Polygonum cuspidatum and its endophytic actinomycete, Streptomyces sp. A0916.

The present study investigated the chemical composition of ethylacetate extracts from an endophytic actinomycete Streptomyces sp. A0916 and its host Polygonum cuspidatum. A comparative analysis of the antimicrobial and antioxidant properties of the extracts was also conducted. 32 compounds of P. cuspidatum and 23 compounds of Streptomyces sp. A0916 were isolated and identified by GC/MS. Antimicrobial activities of the extracts were evaluated using eight microbial strains (3 Gram-positive bacteria, 3 Gram-negative bacteria, and 2 fungi). The Streptomyces sp. A0916 extracts showed a wide range of antimicrobial activities and presented greater antimicrobial effectiveness than the P. cuspidatum extracts. The minimum inhibitory concentration (MIC) of Streptomyces sp. A0916 extracts against the ampicillin-resistant strain Enterococcus faecium SIIA843 was 32 µg·mL(-1). Furthermore, the extracts had greater antimicrobial effect against Gram-positive bacteria than Gram-negative bacteria. Finally, the antioxidant activity of the Streptomyces sp. A0916 extracts was equal to that of the P. cuspidatum extracts. In conclusion, our results suggest that the endophytic actinomycetes of the medicinal plants are an important source of bioactive substances.

Sphingobacterium griseoflavum sp. nov., isolated from the insect Teleogryllus occipitalis living in deserted cropland.

A Gram-stain-negative, aerobic, rod-shaped, non-motile bacterial strain, designated SCU-B140T, was isolated from the insect Teleogryllus occipitalis. Phylogenetic analysis on the basis of 16S rRNA gene sequence showed that strain SCU-B140T belonged to the genus Sphingobacterium. Sphingobacterium bambusae KCTC 22814T (97.87 %) was identified as the most closely related phylogenetic neighbour of strain SCU-B140T. The novel strain was able to grow at salt concentrations of 0-4 % (w/v), at temperatures of 10-40 °C, and at a pH of 6.0-9.0. The major cellular fatty acids were iso-C15 : 0, summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1ω7c), C16 : 0, C16 : 0 3-OH, C18 : 0 and C14 : 0. The major polar lipids consisted of phosphatidylethanolamine, three unknown aminophospholipids, an unknown glycolipid and three unknown polar lipids. MK-7 was the major isoprenoid quinone. The DNA G+C content was 41.2 mol%. The DNA-DNA relatedness value between SCU-B140T and S. bambusae KCTC 22814T was found to be 30.15 %. According to these results, strain SCU-B140T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium griseoflavum sp. nov. is proposed. The type strain is SCU-B140T ( = KCTC 42158T = CGMCC 1.12966T).

Erwinia teleogrylli sp. nov., a Bacterial Isolate Associated with a Chinese Cricket.

A bacterial isolate (SCU-B244T) was obtained in China from crickets (Teleogryllus occipitalis) living in cropland deserted for approximately 10 years. The isolated bacteria were Gram-negative, facultatively anaerobic, oxidase-negative rods. A preliminary analysis of the 16S rRNA gene sequence indicated that the strain belongs to either the genus Erwinia or Pantoea. Analysis of multilocus sequence typing based on concatenated partial atpD, gyrB and infB gene sequences and physiological and biochemical characteristics indicated that the strain belonged to the genus Erwinia, as member of a new species as it was distinct from other known Erwinia species. Further analysis of the 16S rRNA gene showed SCU-B244T to have 94.71% identity to the closest species of that genus, Erwinia oleae (DSM 23398T), which is below the threshold of 97% used to discriminate bacterial species. DNA-DNA hybridization results (5.78±2.52%) between SCU-B244T and Erwinia oleae (DSM 23398T) confirmed that SCU-B244T and Erwinia oleae (DSM 23398T) represent different species combined with average nucleotide identity values which range from 72.42% to 74.41. The DNA G+C content of SCU-B244T was 55.32 mol%, which also differs from that of Erwinia oleae (54.7 to 54.9 mol%). The polyphasic taxonomic approach used here confirmed that the strain belongs to the Erwinia group and represents a novel species. The name Erwinia teleogrylli sp. nov. is proposed for this novel taxon, for which the type strain is SCU-B244T (= CGMCC 1.12772T = DSM 28222T = KCTC 42022T).

Oceanobacillus damuensis sp. nov. and Oceanobacillus rekensis sp. nov., isolated from saline alkali soil samples.

Two moderately halophilic strains, PT-11(T) and PT-20(T), were isolated from saline alkali soil samples collected in Shache County, Xinjiang Province, China. Both strains are aerobic, Gram-positive, motile rods. Strain PT-11(T) grows at 15-40 °C and at pH 6.5-10.0, while PT-20(T) grows at 15-40 °C and at pH 6.5-11.0. The major cellular fatty acids in both strains include anteiso-C15:0, anteiso-C17:0 and iso-C15:0. For both strains, the polar lipids consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and several unidentified lipids. In addition, strain PT-20(T) also contains phosphatidylcholine. The major isoprenoid quinone for both strains is MK-7. The genomic G+C content is 36.7 % for PT-11(T) and 39.2 % for PT-20(T). Phylogenetic analyses of 16S rRNA gene sequences indicated that these two isolates are members of the genus Oceanobacillus. DNA-DNA hybridization indicated that strains PT-11(T) and PT-20(T) should be considered two distinct species. On the basis of both phylogenetic and chemotaxonomic data analyses, therefore, we conclude that PT-11(T) and PT-20(T) represent two novel species within the genus Oceanobacillus, for which we propose the names Oceanobacillus rekensis sp. nov. and Oceanobacillus damuensis sp. nov., respectively. The type strains are PT-11(T) (=KCTC 33144(T) = DSM 26900(T)) and PT-20(T) (=KCTC 33146(T) = DSM 26901(T)).

Speciation analysis of aluminium(III) in natural waters and biological fluids by complexing with various catechols followed by differential pulse voltammetry detection.

The biological effects of aluminium have received much attention in recent years. Speciation of Al is of basic relevance as it concerns its reactivity and bioavailability. A differential pulse voltammetry (DPV) procedure is proposed for speciation analysis of Al(III) in natural waters and biological fluids using six catechols (L-dopa, dopamine, epinephrine, norepinephrine, caffeic acid and o-benzenediol) as electroactive ligands. The decrease of the DPV anodic peak current for each catechol ligand is linear with the increase of Al concentration. This speciation analysis idea is based on the measurement of the complexation capacity, namely, different affinities of Al(III) for catechols and organic ligands under two pH conditions. The labile monomeric Al fraction (mainly inorganic aluminium) is determined at pH 4.6, while the total monomeric Al fraction is determined at pH 8.5. The principle for Al(III) speciation analysis by an electrochemical method is discussed. This sensitive and simple fractionation method is successfully applied to the speciation analysis of Al in natural waters and the results agree well with those of Driscoll's method. The speciation analysis of Al in biological fluids is also explored and the results are compared with those obtained by ultrafiltration and dialysis. Compared with other speciation protocols the electrochemical method possesses some remarkable advantages: rapidity, high sensitivity, cheap instrumentation and a simple operation procedure.