Paenibacillus puerhi sp. nov., isolated from the rhizosphere soil of Pu-erh tea plants (Camellia sinensis var. assamica).

An aerobic, Gram-staining-positive, rod-shaped, endospore-forming and motile bacterial strain, designated SJY2T, was isolated from the rhizosphere soil of tea plants (Camellia sinensis var. assamica) collected in the organic tea garden of the Jingmai Pu-erh tea district in Pu'er city, Yunnan, southwest China. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Paenibacillus. The closest phylogenetic relative was Paenibacillus filicis DSM 23916T (98.1% similarity). The major fatty acids (> 10% of the total fatty acids) were anteiso-C15:0 and isoC16:0. The major respiratory quinone was MK-7 and the major polar lipid was diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylmonomethylethanolamine. The peptidoglycan contained glutamic acid, serine, alanine and meso-diaminopimelic acid. Genome sequencing revealed a genome size of 6.71 Mbp and a G + C content of 53.1%. Pairwise determined whole genome average nucleotide identity (gANI) values and digital DNA-DNA hybridization (dDDH) values suggested that strain SJY2T represents a new species, for which we propose the name Paenibacillus puerhi sp. nov. with the type strain SJY2T (= CGMCC 1.17156T = KCTC 43242T).

Paenibacillus flagellatus sp. nov., isolated from selenium mineral soil.

Strain DXL2T, a Gram-stain-negative, rod-shaped, endospore-forming, motile, aerobic bacterium, was isolated from selenium mineral soil. DXL2T had the highest 16S rRNA gene sequence similarities with those of Paenibacillus ginsengarviGsoil 139T (96.8 %), Paenibacillushemerocallicola DLE-12T (95.5 %) and Paenibacillus hodogayensisSGT (95.4 %). The genome size of DXL2T was 7.24 Mb, containing 6243 predicted protein-coding genes, with a DNA G+C content of 60.2 mol%. DXL2T contained meso-diaminopimelic acid in the cell-wall peptidoglycan. The major cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0 and iso-C15 : 0. The major quinone was menaquinone 7. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two aminophospholipids, an unidentified aminolipid, phosphatidylmethylethanolamine, an unidentified glycolipid and an unidentified phospholipid. Compared with the other strains, DXL2T had a specific phospholipid and a specific aminolipid, it hydrolyzed Tween 40 and could not assimilate potassium gluconate. On the basis of the phenotypic, chemotaxonomic and phylogenetic results, strain DXL2T represents a novel species within the genus Paenibacillus, for which the name Paenibacillusflagellatus sp. nov. is proposed. The type strain is DXL2T (=KCTC 33976T=CCTCC AB 2018054T).

Paenibacillus panacihumi sp. nov., a potential plant growth-promoting bacterium isolated from ginseng-cultivated soil.

A novel bacterium, designated DCY114T, was isolated from ginseng-cultivated soil in Gochang-gun, Republic of Korea. This isolate was assigned to the genus Paenibacillus and is closely related to Paenibacillus amylolyticus NRRL NRS-290T (98.3%), P. dongdonensis KUDC0114T (98.0%), P. tylopili MK2T (97.9%), P. tundrae A10bT (97.8%), and P. xylanexedens B22aT (97.5%) based on 16S rRNA gene sequence analysis. Strain DCY114T is a Gram-reaction positive, catalase and oxidase positive, facultatively aerobic rod that is motile by peritrichous flagella. Strain DCY114T produces siderophores and indole-3-acetic acid (IAA) and is able to solubilize phosphate as a plant growth-promoting bacterium. MK-7 was the diagnostic menaquinone. The major cellular fatty acids were anteiso-C15:0, C16:0, and C18:0, and the major polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), and an unknown amino lipid (AL1,2). The genomic DNA G + C content was 46.0 mol%. Phenotypic and chemotaxonomic results also placed strain DCY114T within the genus Paenibacillus. DNA-DNA homology values between strain DCY114T and closely related reference strains were lower than 43%. The low DNA relatedness data in combination with phylogenetic and biochemical tests indicated that strain DCY114T could not be assigned to a recognized species. The results of this study support that the DCY114T strain is a novel species belonging to the genus Paenibacillus, for which the name Paenibacillus panacihumi is proposed. The type strain is DCY114T (= KCTC 33915T = JCM 32073T).

Paenibacillus eucommiae sp. nov., isolated from a traditional Chinese medicinal herbal plant, Eucommia ulmoides Oliver.

The taxonomic status of a novel bacterium, designated strain CPCC 100226T, isolated from a traditional Chinese medicinal herbal plant, Eucommia ulmoides Oliver, was characterized by using a polyphasic approach. The aerobic isolate formed pale white colonies on tryptic soy agar. Cells were Gram-stain-positive, rod-shaped, motile and endospore-forming. Chemotaxonomic investigations revealed the presence of meso-diaminopimelic acid as the diagnostic diamino acid, MK-7 as the predominant menaquinone, anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0 and C16 : 0 as the major fatty acids, and the strain had a phospholipid pattern of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and unidentified aminophospholipids. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the isolate was closely related to Paenibacillus aestuarii DSM 23861T with 95.1 % similarity. The G+C content of the genomic DNA was 47.9 mol%. On the basis of the genotypic and phenotypic data, the isolate is considered to represent a novel species of the genus Paenibacillus. The name proposed for this taxon is Paenibacillus eucommiae sp. nov. with CPCC 100226T (=DSM 26048T=KCTC 33054T) as the type strain.

Paenibacillus solani sp. nov., isolated from potato rhizosphere soil.

A novel Gram-stain-positive, endospore-forming bacterium, designated FJAT-22460T, was isolated from a soil sample of a potato field in Xinjiang Autonomous Region, China. Cells were rods that were catalase-positive and motile by peritrichous flagella. The strain was found to grow at temperatures ranging from 10 to 40 °C (optimum 30 °C) and at pH 5.0-12.0 (optimum pH 7) with 0-5 % (w/v) NaCl (optimum 0 % NaCl). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain FJAT-22460T belonged to the genus Paenibacillus and exhibited 16S rRNA gene sequence similarities of 97.3, 97.2, 97.2 and 97.0 % with Paenibacillus glucanolyticus DSM 5162T, Paenibacillus lautus DSM 3035T, Paenibacillus lactis MB 1871T and Paenibacillus chibensis JCM 9905T, respectively. DNA-DNA relatedness of strain FJAT-22460T with Paenibacillus glucanolyticusDSM 5162T and Paenibacillus lautus DSM 3035T was 62.6 % and 33.3 %, respectively, lower than the 70 % accepted for species delineation. The menaquinone was identified as MK-7. The major fatty acids detected were anteiso-C15 : 0 (51.4 %), iso-C15 : 0 (5.3 %), C16 : 0 (12.1 %), iso-C16 : 0 (10.7 %) and anteiso-C17 : 0 (6.9 %). The DNA G+C content was determined to be 50.9 mol%. Phenotypic, chemotaxonomic and genotypic properties clearly indicated that isolate FJAT-22460T represents a novel species within the genus Paenibacillus, for which the name Paenibacillus solani sp. nov. is proposed. The type strain is FJAT-22460T (=DSM 100999T=CCTCC AB 2015207T).

Screening and characterization of endophytic Bacillus and Paenibacillus strains from medicinal plant Lonicera japonica for use as potential plant growth promoters.

A total of 48 endophytic bacteria were isolated from surface-sterilized tissues of the medicinal plant Lonicera japonica, which is grown in eastern China; six strains were selected for further study based on their potential ability to promote plant growth in vitro (siderophore and indoleacetic acid production). The bacteria were characterized by phylogenetically analyzing their 16S rRNA gene similarity, by examining their effect on the mycelial development of pathogenic fungi, by testing their potential plant growth-promoting characteristics, and by measuring wheat growth parameters after inoculation. Results showed that the number of endophytic bacteria in L. japonica varied among different tissues, but it remained relatively stable in the same tissues from four different plantation locations. Among the three endophytic strains, strains 122 and 124 both had high siderophore production, with the latter showing the highest phosphate solubilization activity (45.6 mg/L) and aminocyclopropane-1-carboxylic acid deaminase activity (47.3 nmol/mg/h). Strain 170 had the highest indoleacetic acid (IAA) production (49.2 mg/L) and cellulase and pectinase activities. After inoculation, most of the six selected isolates showed a strong capacity to promote wheat growth. Compared with the controls, the increase in the shoot length, root length, fresh weight, dry weight, and chlorophyll content was most remarkable in wheat seedlings inoculated with strain 130. The positive correlation between enzyme (cellulose and pectinase) activity and inhibition rate on Fusarium oxysporum, the IAA production, and the root length of wheat seedlings inoculated with each tested endophytic strain was significant in regression analysis. Deformity of pathogenic fungal mycelia was observed under a microscope after the interaction with the endophytic isolates. Such deformity may be directly related to the production of hydrolytic bacterial enzymes (cellulose and pectinase). The six endophytic bacterial strains were identified to be Paenibacillus and Bacillus strains based on the results of 16S rRNA gene sequencing analysis and their physiological and biochemical characteristics. Results indicate the promising application of endophytic bacteria to the biological control of pathogenic fungi and the improvement of wheat crop growth.

Screening and characterization of endophytic Bacillus and Paenibacillus strains from medicinal plant Lonicera japonica for use as potential plant growth promoters

Abstract A total of 48 endophytic bacteria were isolated from surface-sterilized tissues of the medicinal plant Lonicera japonica, which is grown in eastern China; six strains were selected for further study based on their potential ability to promote plant growth in vitro (siderophore and indoleacetic acid production). The bacteria were characterized by phylogenetically analyzing their 16S rRNA gene similarity, by examining their effect on the mycelial development of pathogenic fungi, by testing their potential plant growth-promoting characteristics, and by measuring wheat growth parameters after inoculation. Results showed that the number of endophytic bacteria in L. japonica varied among different tissues, but it remained relatively stable in the same tissues from four different plantation locations. Among the three endophytic strains, strains 122 and 124 both had high siderophore production, with the latter showing the highest phosphate solubilization activity (45.6 mg/L) and aminocyclopropane-1-carboxylic acid deaminase activity (47.3 nmol/mg/h). Strain 170 had the highest indoleacetic acid (IAA) production (49.2 mg/L) and cellulase and pectinase activities. After inoculation, most of the six selected isolates showed a strong capacity to promote wheat growth. Compared with the controls, the increase in the shoot length, root length, fresh weight, dry weight, and chlorophyll content was most remarkable in wheat seedlings inoculated with strain 130. The positive correlation between enzyme (cellulose and pectinase) activity and inhibition rate on Fusarium oxysporum, the IAA production, and the root length of wheat seedlings inoculated with each tested endophytic strain was significant in regression analysis. Deformity of pathogenic fungal mycelia was observed under a microscope after the interaction with the endophytic isolates. Such deformity may be directly related to the production of hydrolytic bacterial enzymes (cellulose and pectinase). The six endophytic bacterial strains were identified to be Paenibacillus and Bacillus strains based on the results of 16S rRNA gene sequencing analysis and their physiological and biochemical characteristics. Results indicate the promising application of endophytic bacteria to the biological control of pathogenic fungi and the improvement of wheat crop growth.

The coffee-machine bacteriome: biodiversity and colonisation of the wasted coffee tray leach.

Microbial communities are ubiquitous in both natural and artificial environments. However, microbial diversity is usually reduced under strong selection pressures, such as those present in habitats rich in recalcitrant or toxic compounds displaying antimicrobial properties. Caffeine is a natural alkaloid present in coffee, tea and soft drinks with well-known antibacterial properties. Here we present the first systematic analysis of coffee machine-associated bacteria. We sampled the coffee waste reservoir of ten different Nespresso machines and conducted a dynamic monitoring of the colonization process in a new machine. Our results reveal the existence of a varied bacterial community in all the machines sampled, and a rapid colonisation process of the coffee leach. The community developed from a pioneering pool of enterobacteria and other opportunistic taxa to a mature but still highly variable microbiome rich in coffee-adapted bacteria. The bacterial communities described here, for the first time, are potential drivers of biotechnologically relevant processes including decaffeination and bioremediation.

Paenibacillus panaciterrae sp. nov., isolated from ginseng-cultivated soil.

A novel bacterium, designated DCY95T, was isolated from ginseng-cultivated soil in Quang Nam province, Vietnam. On the basis of 16S rRNA and gyrB gene sequence analysis, this isolate was assigned to the genus Paenibacillus and found to be closely related to Paenibacillus sacheonensis SY01T (97.1 % 16S rRNA gene sequence similarity) and Paenibacillus taihuensis THMBG22T (96.4 %). The partial gyrB gene of DCY95T possessed 69.6-83.9 % sequence identity to those of other members of the genus Paenibacillus. Strain DCY95T was Gram-reaction-negative, catalase-negative, oxidase-positive, strictly aerobic, rod-shaped and motile by means of peritrichous flagella. Ellipsoidal free spores or subterminal endospores were produced in sporangia. MK-7 was the diagnostic menaquinone. The cell-wall peptidoglycan contained meso-diamonopimelic acid as the diamino acid. Whole-cell sugars comprised ribose, mannose and glucose. The major cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0 and C16 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminophospholipids, and two unidentified phospholipids. The genomic DNA G+C content was 60.7 ± 0.9 mol%. Phenotypic and chemotaxonomic results placed strain DCY95T within the genus Paenibacillus. However, DNA-DNA relatedness values between strain DCY95T and P. sacheonensis KACC 14895T or P. taihuensis NBRC 108766T were lower than 36 %. The low DNA relatedness data in combination with phylogenetic and (GTG)5-PCR analyses, as well as biochemical tests, indicated that strain DCY95T could not be assigned to any recognized species. In conclusion, the results in this study support the classification of strain DCY95T as a representative of a novel species within the genus Paenibacillus, for which the name Paenibacillus panaciterrae is proposed. The type strain is DCY95T ( = KCTC 33581T = DSM 29477T).

Paenibacillus enshidis sp. nov., Isolated from the Nodules of Robinia pseudoacacia L.

A Gram-positive, motile, endospore-forming, rod-shaped bacterium, designated RP-207(T), was isolated from the nodules of Robinia pseudoacacia L. plants planted in Enshi District, Hubei, PR China. Phylogenetic analyses based on the 16S rRNA gene sequence showed that the novel strain was affiliated to the genus Paenibacillus, with its closest relatives being Paenibacillus xylanilyticus XIL14(T) (95.6%), Paenibacillus peoriae DSM8320(T) (95.3%) and Paenibacillus polymyxa DSM 36(T) (95.3%). The DNA G+C content was 47.0 mol%. DNA-DNA hybridization value between strain RP-207(T) and P. xylanilyticus XIL14(T) was 40.1%. The diamino acid found in the cell wall peptidoglycan was meso-diaminopimelic. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, an unidentified amino-phospholipid and an unknown phospholipid. The predominant menaquinone was menaquinone-7 (MK-7), and the major fatty acid was anteiso-C15:0 and C16:0. On the basis of its physiological and biochemical characteristics and the level of DNA-DNA hybridization, strain RP-207(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus enshidis sp. nov. is proposed. The type strain is RP-207(T) (=CCTCC AB 2013275(T) = KCTC 33519(T)).

Novel bioemulsifier produced by a Paenibacillus strain isolated from crude oil.

BACKGROUND: Surface active compounds produced by microorganisms are attracting a pronounced interest due to their potential advantages over their synthetic counterparts, and to the fact that they could replace some of the synthetics in many environmental and industrial applications. RESULTS: Bioemulsifier production by a Paenibacillus sp. strain isolated from crude oil was studied. The bioemulsifier was produced using sucrose with and without adding hydrocarbons (paraffin or crude oil) under aerobic and anaerobic conditions at 40°C. It formed stable emulsions with several hydrocarbons and its emulsifying ability was not affected by exposure to high salinities (up to 300 g/l), high temperatures (100°C-121°C) or a wide range of pH values (2-13). In addition, it presented low toxicity and high biodegradability when compared with chemical surfactants. A preliminary chemical characterization by Fourier Transform Infrared Spectroscopy (FT-IR), proton and carbon nuclear magnetic resonance (1H NMR and 13C CP-MAS NMR) and size exclusion chromatography indicated that the bioemulsifier is a low molecular weight oligosaccharide-lipid complex. CONCLUSION: The production of a low molecular weight bioemulsifier by a novel Paenibacillus strain isolated from crude oil was reported. To the best of our knowledge, bioemulsifier production by Paenibacillus strains has not been previously reported. The features of this novel bioemulsifier make it an interesting biotechnological product for many environmental and industrial applications. Graphical Abstract Novel bioemulsifier from Paenibacillus sp.

Paenibacillus ginsengiterrae sp. nov., a ginsenoside-hydrolyzing bacteria isolated from soil of ginseng field.

A novel bacterial strain DCY89(T) was isolated from soil sample of ginseng field and was characterized using a polyphasic approach. Cells were Gram-reaction-positive, rod-shaped, spore-forming and motile with flagella. The strain was aerobic, esculin and starch positive, catalase- and oxidase-negative, optimum growth temperature, and pH were 25-30 °C and 6.0-7.5, respectively. On the basis of 16S rRNA gene sequence analysis, strain DCY89(T) was shown to belong to the genus Paenibacillus and the closest phylogenetic relatives were Paenibacillus cellulosilyticus KACC 14175(T) (98.2%), Paenibacillus kobensis KACC 15273(T) (98.1%), Paenibacillus xylaniclasticus KCTC 13719(T) (96.9%), and Paenibacillus curdlanolyticus KCTC 3759(T) (96.64%). The DNA G+C content was 52.5 mol%, and the predominant respiratory quinone was MK-7. The major fatty acids were iso-C15:0, iso-C16:0, and anteiso-C15:0. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol. The results of the genotypic analysis in combination with chemotaxonomic and physiological data demonstrated that DCY89(T) represented a novel species within the genus Paenibacillus, for which we propose the name Paenibacillus ginsengiterrae. The type strain is DCY89(T) (JCM 19887(T) = KCTC 33430(T)).

Feasibility of EPS-producing bacterial inoculation to speed up the sand aggregation in the Gurbantunggut Desert, Northwestern China.

Exopolymers are known to be useful in improving sand aggregation and the development of biological soil crusts (BSCs). A facultative bacterium KLBB0001 was isolated from BSCs in the Gurbantunggut Desert in northwestern China. With the strong effective production of extracellular polymeric substances (EPS), this strain exhibits a multifunctional role for sand stabilization and maintenance of water under laboratory conditions. Practical testing of the feasibility of its inoculation to speed up BSC recovery in the field was also conducted in this experiment. This strain stimulated the heterotrophic community assembly in the topsoil layer (0-2 cm) before the commencement of autotrophic cyanobacteria, while also significantly increasing the number of bacteria, actinomycetes, and content of total phosphorus, available nitrogen, and available phosphorus. However, the low nitrogenase activity (NA) (0.57 µmol/h) that was observed caused us to doubt the previous identification as Azotobacter Beijerinck that was based on physiological and biochemical properties. A phylogenetic analysis based on 16S rRNA gene sequences revealed that this strain was a member of the genus Paenibacillus. It exhibited the closest phylogenetic affinity and highest sequence similarity to the strain Paenibacillus mucilaginosus VKPM B-7519 (sequence similarity 99.698%), which is well known as a typical silicate-weathering bacteria that releases lots of nutritional ions from minerals and the soil. Because P. mucilaginosus can excrete carbonic anhydrase (CA) to capture atmospheric CO2 through hydration of CO2 , it is possible that KLBB0001 might use a similar strategy for heterotrophs in the BSCs to sequester CO2 from the air. Because of its potential role in the reestablishment of the BSC ecosystem due to its ability to improve water relations, sand stabilization, and chemical erosion, EPS-producing bacterial inoculation was concluded to be a suitable and effective treatment for BSC recovery, especially in environments with limited water and nutrients.

Paenibacillus yonginensis sp. nov., a potential plant growth promoting bacterium isolated from humus soil of Yongin forest.

Strain DCY84(T), a Gram-stain positive, rod-shaped, aerobic, spore-forming bacterium, motile by means of peritrichous flagella, was isolated from humus soil from Yongin forest in Gyeonggi province, South Korea. Strain DCY84(T) shared the highest sequence similarity with Paenibacillus barengoltzii KACC 15270(T) (96.86 %), followed by Paenibacillus timonensis KACC 11491(T) (96.49 %) and Paenibacillus phoenicis NBRC 106274(T) (95.77 %). Strain DCY84(T) was found to able to grow best in TSA at temperature 30 °C, at pH 8 and at 0.5 % NaCl. MK-7 menaquinone was identified as the isoprenoid quinone. The major polar lipids were identified as phosphatidylethanolamine, an unidentified aminophospholipid, two unidentified aminolipids and an unidentified polar lipid. The peptidoglycan was found to contain the amino acids meso-diaminopimelic acid, alanine and D-glutamic acid. The major fatty acids of strain DCY84(T) were identified as branched chain anteiso-C15:0, saturated C16:0 and branched chain anteiso-C17:0. The cell wall sugars of strain DCY84(T) were found to comprise of ribose, galactose and xylose. The major polyamine was identified as spermidine. The DNA G+C content was determined to be 62.6 mol%. After 6 days of incubation, strain DCY84(T) produced 52.96 ± 1.85 and 72.83 ± 2.86 µg/ml L-indole-3-acetic acid, using media without L-tryptophan and supplemented with L-tryptophan, respectively. Strain DCY84(T) was also found to be able to solubilize phosphate and produce siderophores. On the basis of the phenotypic characteristics, genotypic analysis and chemotaxonomic characteristics, strain DCY84(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus yonginensis sp. nov. is proposed. The type strain is DCY84(T) (=KCTC 33428(T) = JCM 19885(T)).

Paenibacillus selenii sp. nov., isolated from selenium mineral soil.

Strain W126(T), a Gram-reaction-positive, spore-forming, rod-shaped, facultatively anaerobic bacterium, motile by means of peritrichous flagella, was isolated from selenium mineral soil in Hubei province of China. 16S rRNA gene sequence analysis demonstrated that this isolate belonged to the genus Paenibacillus, with 97.9 % sequence similarity to Paenibacillus anaericanus MH21(T), while compared with the other species of the genus Paenibacillus, the 16S rRNA gene sequence similarities were less than 96.0%. DNA-DNA hybridization between strain W126(T) and Paenibacillus anaericanus DSM 15890(T) was 24%. The major isoprenoid menaquinone was menaquinone-7. Anteiso-C(15 : 0) was the major fatty acid. The DNA G+C content was 42.3 mol%. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unknown aminophospholipids and an unknown lipid. Strain W126(T) contained A1γ-meso-diaminopimelic acid in the cell-wall peptidoglycan. The phenotypic, chemotaxonomic and genotypic data indicate that strain W126(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus selenii sp. nov. is proposed. The type strain is W126(T) ( = KCTC 33420(T) = CCTCC AB 2014003(T)).

Paenibacillus relictisesami sp. nov., isolated from sesame oil cake.

A facultatively anaerobic, Gram-stain-positive, rod-shaped bacterium, designated strain KB0549T, was isolated from sesame oil cake. Cells were motile, round-ended rods, and produced central or terminal spores. The cell wall peptidoglycan contained meso-diaminopimelic acid as the diamino acid. The major fatty acids were anteiso-C15:0 and anteiso-C17:0. The DNA G+C content of strain KB0549T was 51.9 mol%. On the basis of 16S rRNA gene sequence phylogeny, strain KB0549T was affiliated with the genus Paenibacillus in the phylum Firmicutes and was most closely related to Paenibacillus cookii with 97.4% sequence similarity. Strain KB0549T was physiologically differentiated from P. cookii by the high content of anteiso-C17:0, inability to grow at 50 °C, spore position, and negative Voges-Proskauer reaction. Based on these unique physiological and phylogenetic characteristics, it is proposed that the isolate represents a novel species, Paenibacillus relictisesami sp. nov.; the type strain is KB0549T (=JCM 18068T=DSM 25385T).

Paenibacillus selenitireducens sp. nov., a selenite-reducing bacterium isolated from a selenium mineral soil.

A Gram-stain-positive, rod-shaped, facultatively anaerobic bacterium, designated strain ES3-24(T), was isolated from a selenium mineral soil. The isolate was endospore-forming, nitrate-reducing and motile by means of peritrichous flagella. The major menaquinone was menaquinone 7 (MK-7) and the predominant fatty acids (>5%) were anteiso-C15:0, iso-C16:0, C16:0 and anteiso-C17:0. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and two unknown aminophospholipids. Strain ES3-24(T) contained meso-diaminopimelic acid in the cell-wall peptidoglycan and the DNA G+C content was 49.6 mol%. According to phylogenetic analysis based on the 16S rRNA gene sequence, strain ES3-24(T) was most closely related to Paenibacillus terrigena A35(T), with 16S rRNA gene sequence identity of 98.3%, while the other members of the genus Paenibacillus had 16S rRNA gene sequence identities of less than 95.0%. DNA-DNA relatedness between strain ES3-24(T) and P. terrigena CCTCC AB206026(T) was 39.3 %. In addition, strain ES3-24(T) showed obvious differences from closely related species in major polar lipids, nitrate reduction and other physiological and biochemical characteristics. The data from our polyphasic taxonomic study reveal that strain ES3-24(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus selenitireducens sp. nov. is proposed. The type strain is ES3-24(T) ( = KCTC 33157(T) = CCTCC AB2013097(T)).

Optimization of medium for one-step fermentation of inulin extract from Jerusalem artichoke tubers using Paenibacillus polymyxa ZJ-9 to produce R,R-2,3-butanediol.

The medium for one-step fermentation of raw inulin extract from Jerusalem artichoke tubers by Paenibacillus polymyxa ZJ-9 to produce R,R-2,3-butanediol (R,R-2,3-BD) was developed. Inulin, K(2)HPO(4) and NH(4)Cl were found to be the key factors in the fermentation according to the results obtained from the Plackett-Burman experimental design. The optimal concentration range of the three factors was examined by the steepest ascent path, and their optimal concentration was further investigated according to the Box-Behnken design and determined to be 77.14 g/L, 3.09 g/L and 0.93 g/L, respectively. Under the optimal conditions, the concentration of the obtained R,R-2,3-BD was 36.92 g/L, at more than 98% optical purity. Compared with other investigated carbon resources, fermentation of the raw inulin extract afforded the highest yield of R,R-2,3-BD. This process featured one-step fermentation of inulin without further hydrolyzing, which greatly decreased the raw material cost and thus facilitated its practical application.

Effect of bacterial inoculation, plant genotype and developmental stage on root-associated and endophytic bacterial communities in potato (Solanum tuberosum).

Beneficial bacteria interact with plants by colonizing the rhizosphere and roots followed by further spread through the inner tissues, resulting in endophytic colonization. The major factors contributing to these interactions are not always well understood for most bacterial and plant species. It is believed that specific bacterial functions are required for plant colonization, but also from the plant side specific features are needed, such as plant genotype (cultivar) and developmental stage. Via multivariate analysis we present a quantification of the roles of these components on the composition of root-associated and endophytic bacterial communities in potato plants, by weighing the effects of bacterial inoculation, plant genotype and developmental stage. Spontaneous rifampicin resistant mutants of two bacterial endophytes, Paenibacillus sp. strain E119 and Methylobacterium mesophilicum strain SR1.6/6, were introduced into potato plants of three different cultivars (Eersteling, Robijn and Karnico). Densities of both strains in, or attached to potato plants were measured by selective plating, while the effects of bacterial inoculation, plant genotype and developmental stage on the composition of bacterial, Alphaproteobacterial and Paenibacillus species were determined by PCR-denaturing gradient gel-electrophoresis (DGGE). Multivariate analyses revealed that the composition of bacterial communities was mainly driven by cultivar type and plant developmental stage, while Alphaproteobacterial and Paenibacillus communities were mainly influenced by bacterial inoculation. These results are important for better understanding the effects of bacterial inoculations to plants and their possible effects on the indigenous bacterial communities in relation with other plant factors such as genotype and growth stage.