Pleionea litopenaei sp. nov., isolated from the gastric tract of juvenile Pacific white shrimp Litopenaeus vannamei.

A Gram-stain-negative, aerobic, rod-shaped and motile strain HL-JVS1T, was isolated from the gastric tract of a juvenile Pacific white shrimp. Molecular phylogenetic analysis based on 16S rRNA gene sequences of strain HL-JVS1T revealed its affiliation with the genus Pleionea, with close relatives including Pleionea mediterranea MOLA115T (97.5%) and Pleionea sediminis S1-5-21T (96.2%). The complete genome of strain HL-JVS1T consisted of a circular 4.4 Mb chromosome and two circular plasmids (6.6 and 35.0 kb) with a G + C content of 43.1%. The average nucleotide identity and digital DNA-DNA hybridization values between strain HL-JVS1T and the type strains of described Pleionea species were 69.7-70.4% and 18.3-18.6%, respectively. Strain HL-JVS1T grew at 10-40 °C (optimum, 30 °C) in the presence of 0.5 - 9.0% (w/v) sea salts (optimum, 2.0 - 2.5%), and at pH range of 5.5 - 10.0 (optimum, pH 6.5). The major fatty acids (> 10%) were summed feature 9 (iso-C17:1 ω9c and/or C16:0 10-methyl) (23.3%), iso-C16:0 (14.5%), iso-C11:0 3-OH (13.8%) and iso-C15:0 (11.0%). The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminophospholipid, two unidentified aminolipids, and two unidentified lipids. The respiratory quinone was ubiquinone-8. The comprehensive phylogenetic, phylogenomic, phenotypic and chemotaxonomic results showed that strain HL-JVS1T is distinct from other Pleionea species. Hence, we propose strain HL-JVS1T as a novel species belonging to the genus Pleionea, for which the name Pleionea litopenaei sp. nov. is proposed with HL-JVS1T (= KCCM 90514T = JCM 36490T) as the type strain.

Quorum Quenching Potential of Reyranella sp. Isolated from Riverside Soil and Description of Reyranella humidisoli sp. nov.

Quorum quenching refers to any mechanism that inhibits quorum sensing processes. In this study, quorum quenching activity among bacteria inhabiting riverside soil was screened, and a novel Gram-stain-negative, rod shaped bacterial strain designated MMS21-HV4-11T, which showed the highest level of quorum quenching activity, was isolated and subjected to further analysis. Strain MMS21-HV4-11T could be assigned to the genus Reyranella of Alphaproteobacteria based on the 16S rRNA gene sequence, as the strain shared 98.74% sequence similarity with Reyranella aquatilis seoho-37T, and then 97.87% and 97.80% sequence similarity with Reyranella soli KIS14-15T and Reyranella massiliensis 521T, respectively. The decomposed N-acyl homoserine lactone was restored at high concentrations under acidic conditions, implying that lactonase and other enzyme(s) are responsible for quorum quenching. The genome analysis indicated that strain MMS21-HV4-11T had two candidate genes for lactonase and one for acylase, and expected protein structures were confirmed. In the quorum sensing inhibition assay using a plant pathogen Pectobacterium carotovorum KACC 14888, development of soft rot was significantly inhibited by strain MMS21-HV4-11T. Besides, the swarming motility by Pseudomonas aeruginosa PA14 was significantly inhibited in the presence of strain MMS21-HV4-11T. Since the isolate did not display direct antibacterial activity against either of these species, the inhibition was certainly due to quorum quenching activity. In an extended study with the type strains of all known species of Reyranella, all strains were capable of degrading N-acyl homoserine lactones (AHLs), thus showing quorum quenching potential at the genus level. This is the first study on the quorum quenching potential and enzymes responsible in Reyranella. In addition, MMS21-HV4-11T could be recognized as a new species through taxonomic characterization, for which the name Reyranella humidisoli sp. nov. is proposed (type strain = MMS21-HV4-11 T = KCTC 82780 T = LMG 32365T).

Rummeliibacillus suwonensis: First Time Isolation from Human Feces by Culturomics.

Gut microbiota is a complex ecosystem composed by trillions of microorganisms that are crucial for human health or disease status. Currently, there are two methodological options to explore its complexity: metagenomics and culturomics. Culturomics is an approach that uses multiple culture conditions (days of incubation, enrichment factors and growth temperature) and MALDI-TOF mass spectrometry for the identification of bacterial species and sequencing when this method fails. In this paper, we describe how Colturomic's protocol has allowed the first isolation in human sample of Rummeliibacillus suwonensis, a Gram positive, facultative anaerobe bacterium. The bacterium was isolated from feces of a 69 years old male with amyotrophic lateral sclerosis (ALS) recruited for a clinical trial assessing safety and efficacy of fecal microbiota transplantation in ALS. The first isolation of the microorganism dates back to 2013 from the soil of a South Korean mountain area. In this report, morphological description, biochemical characterization and antibiotic susceptibility tests were performed to outline the bacterial properties.

Genomic insights revealed the environmental adaptability of Planococcus halotolerans Y50 isolated from petroleum-contaminated soil on the Qinghai-Tibet Plateau.

The Tibetan Plateau niche provides unprecedented opportunities to find microbes that are functional and commercial significance. The present study investigated the physiological and genomic characteristics of Planococcus halotolerans Y50 that was isolated from a petroleum-contaminated soil sample from the Qinghai-Tibet Plateau, and it displayed psychrotolerant, antiradiation, and oil-degraded characteristics. Whole genome sequencing indicated that strain Y50 has a 3.52 Mb genome and 44.7% G + C content, and it possesses 3377 CDSs. The presence of a wide range of UV damage repair genes uvrX and uvsE, DNA repair genes radA and recN, superoxide dismutase, peroxiredoxin and dioxygenase genes provided the genomic basis for the adaptation of the plateau environment polluted by petroleum. Related experiments also verified that the Y50 strain could degrade n-alkanes from C11-C23, and approximately 30% of the total petroleum at 25 °C within 7 days. Meanwhile, strain Y50 could withstand 5 × 103 J/m2 UVC and 10 KGy gamma ray radiation, and it had strong antioxidant and high radical scavengers for superoxide anion, hydroxyl radical and DPPH. In addition, pan-genome analysis and horizontal gene transfers revealed that strains with different niches have obtained various genes through horizontal gene transfer in the process of evolution, and the more similar their geographical locations, the more similar their members are genetically and ecologically. In conclusion, P. halotolerans Y50 possesses high potential of applications in the bioremediation of alpine hydrocarbons contaminated environment.

Diet and gut microbiome enterotype are associated at the population level in African buffalo.

Studies in humans and laboratory animals link stable gut microbiome "enterotypes" with long-term diet and host health. Understanding how this paradigm manifests in wild herbivores could provide a mechanistic explanation of the relationships between microbiome dynamics, changes in dietary resources, and outcomes for host health. We identify two putative enterotypes in the African buffalo gut microbiome. The enterotype prevalent under resource-abundant dietary regimes, regardless of environmental conditions, has high richness, low between- and within-host beta diversity, and enrichment of genus Ruminococcaceae-UCG-005. The second enterotype, prevalent under restricted dietary conditions, has reduced richness, elevated beta diversity, and enrichment of genus Solibacillus. Population-level gamma diversity is maintained during resource restriction by increased beta diversity between individuals, suggesting a mechanism for population-level microbiome resilience. We identify three pathogens associated with microbiome variation depending on host diet, indicating that nutritional background may impact microbiome-pathogen dynamics. Overall, this study reveals diet-driven enterotype plasticity, illustrates ecological processes that maintain microbiome diversity, and identifies potential associations between diet, enterotype, and disease.

Planococcus maritimus ML1206 Isolated from Wild Oysters Enhances the Survival of Caenorhabditis elegans against Vibrio anguillarum.

With the widespread occurrence of aquaculture diseases and the broad application of antibiotics, drug-resistant pathogens have increasingly affected aquatic animals' health. Marine probiotics, which live under high pressure in a saltwater environment, show high potential as a substitute for antibiotics in the field of aquatic disease control. In this study, twenty strains of non-hemolytic bacteria were isolated from the intestine of wild oysters and perch, and a model of Caenorhabditis elegans infected by Vibrio anguillarum was established. Based on the model, ML1206, which showed a 99% similarity of 16S rRNA sequence to Planococcus maritimus, was selected as a potential marine probiotic, with strong antibacterial capabilities and great acid and bile salt tolerance, to protect Caenorhabditis elegans from being damaged by Vibrio anguillarum. Combined with plate counting and transmission electron microscopy, it was found that strain ML1206 could significantly inhibit Vibrio anguillarum colonization in the intestinal tract of Caenorhabditis elegans. Acute oral toxicity tests in mice showed that ML1206 was safe and non-toxic. The real-time qPCR results showed a higher expression level of genes related to the antibacterial peptide (ilys-3) and detoxification (ugt-22, cyp-35A3, and cyp-14A3) in the group of Caenorhabditis elegans protected by ML1206 compared to the control group. It is speculated that ML1206, as a potential probiotic, may inhibit the infection caused by Vibrio anguillarum through stimulating Caenorhabditis elegans to secrete antibacterial effectors and detoxification proteins. This paper provides a new direction for screening marine probiotics and an experimental basis to support the potential application of ML1206 as a marine probiotic in aquaculture.

Genome sequencing of cold-adapted Planococcus bacterium isolated from traditional shrimp paste and protease identification.

BACKGROUND: Psychrophiles have evolved to adapt to freezing environments, and cold-adapted enzymes from these organisms can maintain high catalytic activity at low temperature. The use of cold-adapted enzymes has great potential for the revolution of food and molecular biology industries. RESULTS: In this study, four different strains producing protease were isolated from traditional fermented shrimp paste, one of which, named Planococcus maritimus XJ11 by 16S rRNA nucleotide sequence analysis, exhibited the largest protein hydrolysis clear zone surrounding the colonies. Meanwhile, the strain P. maritimus XJ11 was selected for further investigation because of its great adaptation to low temperature, low salinity and alkaline environment. The enzyme activity assay of P. maritimus XJ11 indicated that the optimum conditions for catalytic activity were pH 10.0 and 40 °C. Moreover, the enzyme also showed an increasing activity with temperatures from 10 to 40 °C and retained more than 67% activity of the maximum over a broad range of salinity (50-150 g L-1 ). Genome sequencing analysis revealed that strain XJ11 possessed one circular chromosome of 3 282 604 bp and one circular plasmid of 67 339 bp, with a total number of 3293 open reading frames (ORFs). Besides, 21 genes encoding protease, including three serine proteases, were identified through the NR database. CONCLUSION: Cold-adapted bacterium P. maritimus XJ11 was capable of producing alkaline proteases with high catalytic efficiency at low or moderate temperatures. Furthermore, the favorable psychrophilic and enzymatic characters of strain P. maritimus XJ11 seem to have a promising potential for industrial application. © 2020 Society of Chemical Industry.

Indiicoccus explosivorum gen. nov., sp. nov., isolated from an explosives waste contaminated site.

A pink-pigmented, Gram-stain-positive, aerobic, coccoid-shaped bacterial strain, designated as S5-TSA-19T, was isolated from an explosives contaminated site in Panchkula, Haryana, India. The 16S rRNA gene sequencing blast analysis indicated that the strain is a member of the family Planococcaceae with the highest sequence similarity to Planomicrobium soli XN13T (96.1 %), followed by Planococcus maitriensis S1T (95.6 %), Planococcus plakortidis DSM 23997T (95.6 %), Planomicrobium flavidum ISL-41T (95.6 %), Planococcus rifietoensis M8T (95.5 %), Planococcus salinus LCB217T (95.5 %) and Planococcus maritimus DSM 17275T (95.5 %). Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences (based on a conserved set of 400 proteins) retrieved the strain in a distinct branch indicating a separate lineage within the family Planococcaceae. Strain S5-TSA-19T had a distinctive chemotaxonomic pattern comprising A4α type peptidoglycan based on l-Lys-d-Asp, iso-C15 : 0 as the major fatty acid, absence of phosphatidylethanolamine as a major lipid and MK-7 and MK-6 as the major menaquinones, differentiating it from the genera Planococcus and Planomicrobium, thus supporting the findings of molecular phylogeny. Further, strain S5-TSA-19T was able to biotransform hexahydro-1,3,5,-trinitro-1,2,5-triazine (RDX) into nitrite derivatives under aerobic conditions in 2-4 days, whereas the closest reference strains did not possess this property. On the basis of polyphasic taxonomic characterization and a phylogenomics approach, strain S5-TSA-19T is proposed as the type strain of a novel species in a novel genus for which the name Indiicoccus explosivorum gen. nov., sp. nov. is proposed (=JCM 31737T=KCTC 33871T=MTCC 12608T).

Filibacter tadaridae sp. nov., isolated from within a guano pile from a colony of Mexican free-tailed bats Tadarida brasiliensis.

A Gram-stain-positive, aerobic bacterium, TB-66T, was isolated from a pile of bat guano in a cave of New Mexico, USA. On the basis of 16S rRNA gene sequence similarity comparisons, strain TB-66Tgrouped together with Filibacter limicola showing a 16S rRNA gene sequence similarity of 98.5 % to the type strain. The quinone system of strain TB-66T consisted predominantly of menaquinone MK-7. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylserine and three unidentified phospholipids. The peptidoglycan type was A4α l-Lys-d-Glu (A11.33). The major fatty acids were C15 : 0 anteiso, C16 : 0, and C16 : 1 ω7c. The G+C content of the genomic DNA was 37.6 (±1.8) mol%. On the basis of the genotypic and phenotypic properties it is clear that strain TB-66T represents a member of the genus Filibacter, but is distinct from the only other species in the genus, Filibacter limicola DSM 13886T. We propose a novel species with the name Filibacter tadaridae sp. nov. The type strain is TB-66T (= CIP 111629T= LMG 30660T= CCM 8866T).

The stimulatory effects of plant growth promoting rhizobacteria and plant growth regulators on wheat physiology grown in sandy soil.

The present study was aimed to investigate the effects of plant growth promoting rhizobacteria (PGPR) and plant growth regulators (PGRs) on the physiology and yield of wheat grown in less fertile sandy soil. The isolated PGPR strains were identified by 16S-rRNA gene sequencing as Planomicrobium chinense (P1), Bacillus cereus (P2) and Pseudomonas fluorescens (P3). Wheat varieties (Galaxy-13 and Pak-2013) differing in sensitivity to drought were soaked in fresh cultures of bacterial isolates and the PGRs (salicylic acid and putrescine) were sprayed at 150 mg/L on seedlings at three leaf stage. PGPR and PGRs treated plants showed significant increase in the contents of chlorophyll, sugar and protein even under harsh environmental conditions. Drought stress enhanced the production of proline, antioxidant enzymes and lipid peroxidation but a decrease was noted in the biochemical content (i.e. chlorophyll, protein and sugar) of inoculated plants. PGPR inoculation also significantly enhanced the yield parameters (i.e. plant height, spike length, grain yield and weight) and improved the fertility status of sandy soil. The accumulation of macronutrient, total NO3-N and P concentration and soil moisture content of rhizosphere soil was also enhanced by PGPRs inoculation. It is concluded that the combined effects of PGPR and PGRs have profound effects on the biochemical responses and drought tolerance of wheat grown in sandy soils.

Planomicrobium iranicum sp. nov., a novel slightly halophilic bacterium isolated from a hypersaline wetland.

A novel strain, designated as MX6T was isolated from Meighan wetland, in the centre of Iran. The cells were Gram-stain-positive, motile, coccoid to rod-shaped, oxidase- and catalase-positive. The strain grew optimally at 35 °C, 3 % (w/v) NaCl and pH 7-7.5. A polyphasic taxonomic study was undertaken in order to characterize the strain in detail. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that MX6T represented a member of the phylum Firmicutes, family Planococcaceae, genus Planomicrobium, and showed the highest similarity with Planomicrobium flavidum ISL-41T (98.2 %) and Planomicrobium psychrophilum CMC 53orT (98.0 %). The main polar lipids of MX6T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and seven unidentified phospholipids and its DNA G+C content was 45.5 mol%. Major cellular fatty acids were anteiso-C15 : 0, C16 : 1ω7c alcohol, iso-C14 : 0, iso-C15 : 0 and iso-C16 : 0 and the predominant respiratory quinone was Q-8 (62 %). Experimental DNA-DNA hybridization between MX6T and Planomicrobium flavidum IBRC-M 11047T was 20 %, supporting the differential taxonomic status of MX6T as representing a different taxon. All these data indicate that MX6T represents a novel species of the genus Planomicrobium, for which the name Planomicrobium iranicum sp. nov. is proposed. The type strain is MX6T (=IBRC M 10928T=LMG 28548T).

Jeotgalibacillus proteolyticus sp. nov., a protease-producing bacterium isolated from ocean sediments.

A Gram-stain-positive, rod-shaped bacterial strain, 22-7T, was isolated from ocean sediment of Laizhou Bay, China, and was characterized by using a polyphasic approach. Optimal growth was observed at 33 °C on a 2216E agar plate of pH 7.5 and with 2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences identified it as a member of the genus Jeotgalibacillus, most similar to Jeotgalibacillus campisalis SF-57T (98.7 % similarity), Jeotgalibacillus marinus DSM 1297T (98.2 %) and Jeotgalibacillus soli P9T (97.1 %). Average nucleotide identity values and digital DNA-DNA hybridization values were less than 74.2 and 18.1 %, respectively, between strain 22-7T and the type strains of closely related species. The major polar lipids were aminophospholipid, phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol; the major fatty acids (>10 %) were anteiso-C15 : 0 and iso-C15 : 0; and the major menaquinone was MK-7. The peptidoglycan type of the cell wall was A1α linked through l-lysine as the diamino acid. Combined data from phenotypic, chemotaxonomic and genotypic characterizations demonstrated that strain 22-7T represents a novel Jeotgalibacillus species, for which the name Jeotgalibacillus proteolyticus sp. nov. is proposed. The type strain is 22-7T(=MCCC 1H00228T=KCTC 33930T).

Simplistic approach in extracellular synthesis of silver nanoparticles via bioreducing potential of Planococcus plakortidis strain BGCC-51 isolated from dye industry effluent soil.

Here, extracellular synthesis of silver nanoparticles (AgNPs) was carried out by Planococcus plakortidis strain BGCC-51 isolated from dye industry effluent soil. The microbes were isolated, screened, and characterised by molecular analysis (accession number KX776160). The optimisation of synthesis of AgNPs to determine the optimum substrate level (1-5 mM), pH (5-9), and temperature (25-55°C) were further carried out. P. plakortidis strain BGCC-51 gave best yield of AgNPs at substrate concentration 5 mM, pH 8, and at 35°C. Synthesised AgNPs were characterised by scanning electron microscope and high-resolution transmission electron microscope. The size of synthesised AgNPs was in the range of 20-40 nm having spherical morphology. The AgNPs were found to show antimicrobial activity against bacteria such as Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), and Staphylococcus aureus (ATCC 29213).

Bhargavaea changchunensis sp. nov. isolated from soil in China.

A Gram-staining-positive, aerobic, rod-shaped (201802YP6T) bacteria was isolated from soil, Northeast of China. Growth occurred at 10-40 °C (optimum 25-30 °C), at pH 6.0-8.0 (optimum 7.0) and at 0-2% NaCl. Based on 16S rRNA gene sequence analysis, the nearest phylogenetic neighbors of strain 201802YP6T were identified as Bhargavaea cecembensis DSE10T (99.52%), Bhargavaea beijingensis ge10T (99.45%), Bhargavaea indica KJW98T (99.45%), Bhargavaea ullalensis ZMA19T (98.81%), and Bhargavaea ginsengi ge14T (98.76%). Levels of similarity among strain 201802YP6T and other Bhargavaea species were lower than 98.76%. GyrB amino acid sequence-based analysis supported the phylogenetic position and also distinguished strain 201802YP6T from the other species of the genus Bhargavaea. DNA-DNA hybridization values between strain 201802YP6T and B. cecembensis, B. beijingensis, B. indica, B. ullalensis, B. ginsengi were 43.5%, 43%, 32.5%, 30.5% and 20.4%, respectively. The DNA G + C content of strain 201802YP6T was 51.23 mol%. The average nucleotide identity (ANI) of the draft genome was 87.04% to B. cecembensis DSE10T. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, glycolipids, phosphatidylethanolamine, and phosphatidyllipid. The predominant menaquinone was MK-8. The major fatty acids were iso-C15:0 (39.91%), anteiso-C15:0 (28.86%), anteiso-C17:0 (6.30%) and C16:0 (6.13%). On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain 201802YP6T represents a novel species of the genus Bhargavaea, for which the name Bhargavaea changchunensis sp. nov. is proposed. The type strain is 201802YP6T (= CGMCC 1.13508T = KCTC 33975T).

Chryseomicrobium excrementi sp. nov., a Gram-stain-positive rod-shaped bacterium isolated from an earthworm (Eisenia fetida) cast.

A Gram-stain-positive, rod-shaped, slightly halotolerant, nitrate-reducing bacterial strain, designated ET03T, was isolated from the cast of an earthworm (Eisenia fetida) reared at the Centre of Floriculture and Agribusiness Management, University of North Bengal at Siliguri, West Bengal, India. On the basis of 16S rRNA gene sequence phylogeny, the closest relative of strain ET03T was Chryseomicrobium palamuruense PU1T (99.1 % similarity). The DNA G+C content of strain ET03T was 42.9 mol%. Strain ET03T contained menaquinone-8 as the most predominant menaquinone and phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and phosphatidylglycerol as the main polar lipids. The diagnostic diamino acid was meso-diaminopimelic acid. Major cellular fatty acids were iso-C15 : 0, C16 : 1ω7c alcohol and iso-C16 : 0. Other biochemical and physiological analyses supported genotypic and phenotypic differentiation of the strain ET03T from its nearest taxonomic neighbours: Chryseomicrobium palamuruense,Chryseomicrobium amylolyticum, Chryseomicrobium imtechense, Chryseomicrobium aureum and Chryseomicrobium deserti. The draft genome of strain ET03T consisted of 2.64 Mb distributed in 14 scaffolds (N50 894072). A total of 2728 genes were predicted and, of those, 2664 were protein-coding genes including genes involved in the degradation of polychlorinated biphenyl and several aromatic compounds. The isolate, therefore, represents a novel species, for which the name Chryseomicrobium excrementi sp. nov. is proposed. The type strain is ET03T (=KCTC 33943T=LMG 30119T=JCM 32415T).

Characterization of Solibacillus silvestris strain AM1 that produces amyloid bioemulsifier.

Solibacillus silvestris AM1 was the first strain from the genus to be reported for the production of a functional amyloid and its potential use as a surface active agent, a thermostable glycoprotein amyloid bioemulsifier BE-AM1 capable of influencing environment and biofilm formation. Phylogenetic analysis based on 16S rRNA gene, molecular characterization studies on the basis of DNA-DNA hybridization and chemotaxonomic fatty acid methyl ester (FAME) analysis showed that S. silvestris AM1 as a strain matches with the type strain S. silvestris HR3-23. But strain AM1 differs from the type strain HR3-23 in carbon substrate utilization studies along with amyloid bioemulsifier production ability with potential industrial and environmental applications. S. silvestris AM1 exhibited bioemulsifier production at wide range of factors like pH and NaCl concentrations, while temperature influenced the bioemulsifier production indirectly (since it affected the growth). Bioemulsifier production was observed even at oligotrophic conditions (0.5 mg ml-1 ) seen usually in its native environment. In this study, we have characterized the amyloid producing S. silvestris AM1 taxonomically and also analyzed 16S rDNA of 103 sequences of Solibacillus sp. available, which indicated the possibility of new species in this genus and can be studied for industrially and environmentally important biomolecules.

A phytobeneficial strain Planomicrobium sp. MSSA-10 triggered oxidative stress responsive mechanisms and regulated the growth of pea plants under induced saline environment.

AIMS: The study was planned to characterize Planomicrobium sp. MSSA-10 for plant-beneficial traits and to evaluate its inoculation impact on physiology of pea plants under different salinity levels. METHODS AND RESULTS: Strain MSSA-10 was isolated from pea rhizosphere and identified by the analysis of 16S rRNA gene sequence. The strain demonstrated phosphate solubilization and auxin production up to 2 mol l-1 NaCl and exhibited 1-aminocyclopropane-1-carboxylic acid deaminase activity up to 1·5 mol l-1 salt. In an inoculation experiment under different salinity regimes, a significant increase in growth was observed associated with decreased levels of reactive oxygen species and enhanced antioxidative enzyme activities. The strain also promoted the translocation of nutrients in plants with subsequent increase in chlorophyll and protein contents as compared to noninoculated plants. It has been observed that rifampicin-resistant derivatives of MSSA-10 were able to survive for 30 days at optimum cell density with pea rhizosphere. CONCLUSION: Growth-stimulating effect of MSSA-10 on pea plants may be attributed to its rhizosphere competence, nutrient mobilization and modulation of plant oxidative damage repair mechanisms under saline environment. SIGNIFICANCE AND IMPACT OF THE STUDY: Planomicrobium sp. MSSA-10 might be used as potent bioinoculant to relieve pea plants from deleterious effects of salinity.

Kurthia ruminicola sp. nov., isolated from the rumen contents of a Holstein cow.

Gram-staining-positive, motile, rod-shaped bacteria, designated as H31022T and H31024 was isolated from rumen contents of a Holstein cow. Optimum growth occurred at 25°C and pH 7.0 on R2A agar medium. Oxidase and catalase activities are positive. The 16S rRNA gene sequence (1,452 bp) of the new isolates revealed they belong to the genus Kurthia of the phylum Firmicutes. Highest gene sequence similarities were assessed to be with Kurthia massiliensis JC30T (98.4%), Kurthia senegalensis JC8ET (97.5%), and Kurthia populi 10y-14T (97.4%). Kurthia sibirica DSM 4747T (97.3%), Kurthia zopfii NBRC 101529T (97.0%), and Kurthia gibsonii NCIMB 9758T (96.7%). DNA G + C content of strains H31022T and H31024 were 34.4% and 39.7%. Strains H31022T and H31024 has the following chemotaxonomic characteristics; the major fatty acids are iso-C15:0, iso-C14:0 and anteiso-C15; polar lipid profile contained diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), unknown aminophospholipids (APL), unknown glycolipids (GL), unknown phospholipids (PL), and unknown polar lipids (L); the major quinone is MK-7. Based on polyphasic taxonomic analysis, strains H31022T (= KCTC 33923T = JCM 19640T) and H31024 (= KCTC 33924T = JCM 19641T) identified a novel species in the genus Kurthia for which the name Kurthia ruminicola sp. nov. is proposed.

Chryseomicrobium deserti sp. nov., isolated from desert soil in South Korea.

A Gram-stain positive, aerobic, non-motile, rod-shaped bacterium (THG-T1.18T) was isolated from desert soil. Growth occurred at 20-35 °C (optimum 28-30 °C), at pH 5-7 (optimum 7) and at 0-4 % NaCl (optimum 0-1 %). Based on 16S rRNA sequence analysis, the nearest phylogenetic neighbours of strain THG-T1.18T were identified as Chryseomicrobium amylolyticum DSM 23442T (96.6 %), Chryseomicrobium imtechense JCM 16573T (96.3 %) and Chryseomicrobium aureum KACC 17219T (96.1 %). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids and one unidentified glycolipid. The quinone system was composed of MK-7, MK-8 and MK-6. The major fatty acids were iso C15 : 0 and anteiso C15 : 0. The type of peptidoglycan was A4ß, containing of l-Orn-D-Glu. The DNA G+C content of strain THG-T1.18T was 50.4 mol%. DNA-DNA hybridization values between strain THG-T1.18T and C. amylolyticum DSM 23442T, C. imtechense JCM 16573T, C. aureum KACC 17219T were 24.7 % (20.1 % reciprocal analysis), 19.5 % (16.1 %) and 10.4 % (6.7 %) respectively. On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain THG-T1.18T represents a novel species of the genus Chryseomicrobium, for which the name Chryseomicrobium deserti sp. nov. is proposed. The type strain is THG-T1.18T (=KACC 18929T=CCTCC AB 2016179T).

Solibacillus kalamii sp. nov., isolated from a high-efficiency particulate arrestance filter system used in the International Space Station.

A Gram-stain-positive, rod-shaped, endospore-forming, aerobic bacterial strain, designated ISSFR-015T, was isolated from a high-efficiency particulate arrestance filter in the International Space Station and was characterized by polyphasic taxonomy. A comparative analysis of the 16S rRNA gene sequence (1494 bp) of strain ISSFR-015T showed highest similarity to Solibacillus isronensis B3W22T (98.9 %), followed by Solibacillus silvestris HR3-23T (98.6 %) and Bacillus cecembensis PN5T (96.7 %). DNA-DNA hybridization analysis revealed that the DNA relatedness values of strain ISSFR-015T with other closely related species were in the range of 41-47 % [S. silvestrisMTCC 10789T (47 %), S. isronensis MTCC 7902T (41 %) and B. cecembensis MTCC 9127T (43 %)]. The DNA G+C content of strain ISSFR-015T was 45.4 mol%. The major fatty acids were iso-C15 : 0 (45.2 %) and C17 : 1ω10c (12.1 %). The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine and one unknown phospholipid. The isoprenoid quinones present in strain ISSFR-015T were MK-7 (86.8 %), MK-6 (11.6 %) and MK-8 (1.0 %). The peptidoglycan type of the cell wall was A4α l-Lys-d-Glu. Based on the phylogenetic analysis, strain ISSFR-015T belongs to the genus Solibacillus. The polyphasic taxonomic data, including low DNA-DNA hybridization values, and the chemotaxonomic analysis confirmed that strain ISSFR-015T represents a novel species, for which the name Solibacillus kalamii sp. nov. is proposed. The type strain for this proposed species is ISSFR-015T (=NRRL B-65388T=DSM 101595T).