Oceanobacillus picturae alleviates cadmium stress and promotes growth in soybean seedlings.

Cadmium (Cd) is a heavy metal that significantly impacts human health and the environment. Microorganisms play a crucial role in reducing heavy metal stress in plants; however, the mechanisms by which microorganisms enhance plant tolerance to Cd stress and the interplay between plants and microorganisms under such stress remain unclear. In this study, Oceanobacillus picturae (O. picturae) was isolated for interaction with soybean seedlings under Cd stress. Results indicated that Cd treatment alone markedly inhibited soybean seedling growth. Conversely, inoculation with O. picturae significantly improved growth indices such as plant height, root length, and fresh weight, while also promoting recovery in soil physiological indicators and pH. Metabolomic and transcriptomic analyses identified 157 genes related to aspartic acid, cysteine, and flavonoid biosynthesis pathways. Sixty-three microbial species were significantly associated with metabolites in these pathways, including pathogenic, adversity-resistant, and bioconductive bacteria. This research experimentally demonstrates, for the first time, the growth-promoting effect of the O. picturae strain on soybean seedlings under non-stress conditions. It also highlights its role in enhancing root growth and reducing Cd accumulation in the roots under Cd stress. Additionally, through the utilization of untargeted metabolomics, metagenomics, and transcriptomics for a multi-omics analysis, we investigated the impact of O. picturae on the soil microbiome and its correlation with differential gene expression in plants. This innovative approach unveils the molecular mechanisms underlying O. picturae's promotion of root growth and adaptation to Cd stress.

A novel type IIb L-asparaginase from Latilactobacillus sakei LK-145: characterization and application.

We succeeded in homogeneously expressing and purifying L-asparaginase from Latilactobacillus sakei LK-145 (Ls-Asn1) and its mutated enzymes C196S, C264S, C290S, C196S/C264S, C196S/C290S, C264S/C290S, and C196S/C264S/C290S-Ls-Asn1. Enzymological studies using purified enzymes revealed that all cysteine residues of Ls-Asn1 were found to affect the catalytic activity of Ls-Asn1 to varying degrees. The mutation of Cys196 did not affect the specific activity, but the mutation of Cys264, even a single mutation, significantly decreased the specific activity. Furthermore, C264S/C290S- and C196S/C264S/C290S-Ls-Asn1 almost completely lost their activity, suggesting that C290 cooperates with C264 to influence the catalytic activity of Ls-Asn1. The detailed enzymatic properties of three single-mutated enzymes (C196S, C264S, and C290S-Ls-Asn1) were investigated for comparison with Ls-Asn1. We found that only C196S-Ls-Asn1 has almost the same enzymatic properties as that of Ls-Asn1 except for its increased stability for thermal, pH, and the metals NaCl, KCl, CaCl2, and FeCl2. We measured the growth inhibitory effect of Ls-Asn1 and C196S-Ls-Asn1 on Jurkat cells, a human T-cell acute lymphoblastic leukemia cell line, using L-asparaginase from Escherichia coli K-12 as a reference. Only C196S-Ls-Asn1 effectively and selectively inhibited the growth of Jurkat T-cell leukemia, which suggested that it exhibited antileukemic activity. Furthermore, based on alignment, phylogenetic tree analysis, and structural modeling, we also proposed that Ls-Asn1 is a so-called "Type IIb" novel type of asparaginase that is distinct from previously reported type I or type II asparaginases. Based on the above results, Ls-Asn1 is expected to be useful as a new leukemia therapeutic agent.

Lentibacillus daqui sp. nov., isolated from high-temperature Daqu, a starter for production of Chinese Jiang-flavour Baijiu.

A Gram-stain-positive, rod-shaped, endospore-forming, aerobic bacterial strain, designated ZS110521T, was isolated from high-temperature Daqu, a starter for production of Chinese Jiang-flavour Baijiu and was characterised by polyphasic taxonomy. This novel isolate grew in the presence of 0-20 % (w/v) NaCl, at pH 6.0-9.0 and 20-50 °C; optimum growth was observed with 8-10 % (w/v) NaCl, at pH 7.0 and 37 °C. A comparative analysis of the 16S rRNA gene sequence (1460 bp) of ZS110521T revealed that it displayed the highest similarity to Lentibacillus populi WD4L-1T (95.5 %), followed by Lentibacillus garicola SL-MJ1T (95.4 %) and Lentibacillus lacisalsi BH260T (95.2 %). ANI and dDDH values between ZS110521T and other strains of species of the genus Lentibacillus were less than 78 and 28 %, respectively. The predominant cellular fatty acids (> 10 %) of ZS110521T were anteiso-C17 : 0 (37.8 %), anteiso-C15 : 0 (28.1 %) and iso-C16 : 0 (15.5 %). The respiratory quinone was identified as menaquinone-7 (MK-7) and the major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The polyphasic taxonomic data and the results of chemotaxonomic analysis confirmed that ZS110521T represents a novel species, for which the name Lentibacillus daqui sp. nov. is proposed. The type strain of this proposed species is ZS110521T (=CGMCC 1.19456T =JCM 35213T).

A novel marine bacterium Exiguobacterium marinum a-1 isolated from in situ plastisphere for degradation of additive-free polypropylene.

As the ecological niche most closely associated with polymers, microorganisms in the 'plastisphere' have great potential for plastics degradation. Microorganisms isolated from the 'plastisphere' could colonize and degrade commercial plastics containing different additives, but the observed weight loss and surface changes were most likely caused by releasing the additives rather than actual degradation of the plastics itself. Unlike commercial plastics that contain additives, whether marine microorganisms in the 'plastisphere' have adapted to additive-free plastics as a surface to colonize and potentially degrade is not yet known. Herein, a novel marine bacterium, Exiguobacterium marinum a-1, was successfully isolated from mature 'plastisphere' that had been deployed in situ for up to 20 months. Strain a-1 could use additive-free polypropylene (PP) films as its primary energy and carbon source. After strain a-1 was incubated with additive-free PP films for 80 days, the weight of films decreased by 9.2%. The ability of strain a-1 to rapidly form biofilms and effectively colonize the surface of additive-free PP films was confirmed by Scanning Electron Microscopy (SEM), as reflected by the increase in roughness and visible craters on the surface of additive-free PP films. Additionally, the functional groups of -CO, -C-H, and -OH were identified on the treated additive-free PP films according to Fourier Transform Infrared (FTIR). Genomic data from strain a-1 revealed a suite of key genes involved in biosurfactant synthesis, flagellar assembly, and cellular chemotaxis, contributing to its rapid biofilm formation on hydrophobic polymer surfaces. In particular, key enzymes that may be responsible for the degradation of additive-free PP films, such as glutathione peroxidase, cytochrome p450 and esterase were also recognized. This study highlights the potential of microorganisms present in the 'plastisphere' to metabolize plastic polymers and points to the intrinsic importance of the new strain a-1 in the mitigation of plastic pollution.

Efficient synthesis of 2'-deoxyguanosine in one-pot cascade by employing an engineered purine nucleoside phosphorylase from Brevibacterium acetylicum.

2'-deoxyguanosine is a key medicinal intermediate that could be used to synthesize anti-cancer drug and biomarker in type 2 diabetes. In this study, an enzymatic cascade using thymidine phosphorylase from Escherichia coli (EcTP) and purine nucleoside phosphorylase from Brevibacterium acetylicum (BaPNP) in a one-pot whole cell catalysis was proposed for the efficient synthesis of 2'-deoxyguanosine. BaPNP was semi-rationally designed to improve its activity, yielding the best triple variant BaPNP-Mu3 (E57A/T189S/L243I), with a 5.6-fold higher production of 2'-deoxyguanosine than that of wild-type BaPNP (BaPNP-Mu0). Molecular dynamics simulation revealed that the engineering of BaPNP-Mu3 resulted in a larger and more flexible substrate entrance channel, which might contribute to its catalytic efficiency. Furthermore, by coordinating the expression of BaPNP-Mu3 and EcTP, a robust whole cell catalyst W05 was created, capable of producing 14.8 mM 2'-deoxyguanosine (74.0% conversion rate) with a high time-space yield (1.32 g/L/h) and therefore being very competitive for industrial applications.

Cytobacillus spongiae sp. nov. isolated from sponge Diacarnus spinipoculum.

A novel Gram-stain-positive, aerobic and motile bacterium, designated strain CY-GT, was isolated from a sponge (Diacarnus spinipoculum) collected from the Red Sea. The strain grew at 13-43 °C (optimum 30 °C), pH 5.5-10.0 (optimum pH 9.0) and with 0-8.0 % (w/v) (0-1.37 M) NaCl (optimum 0 %). The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that CY-GT represents a member of the genus Cytobacillus, with the highest sequence identity to Cytobacillus oceanisediminis H2T (97.05 %), followed by Cytobacillus firmus IAM 12464T (96.76 %). The major cellular fatty acids (>5 % of the total) of CY-GT were C15 : 0iso, C16 : 0iso, C16 : 1ω7c alcohol, C16 : 0, C17 : 1iso ω10c and C17 : 0iso. The major polar lipids were glycolipid, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The major respiratory quinone is menaquinone-7 (MK-7). The cell-wall peptidoglycan contains meso-diaminopimelic acid. The total genome size of CY-GT is 4 789 051 bp. The DNA G+C content is 38.83 mol%. The average nucleotide identity and DNA-DNA hybridization among CY-GT and type strains of other species of the genus Cytobacillus were 76.79-78.97 % and 20.10-24.90 %, respectively. On the basis of the results of phylogenetic analysis, physiological and biochemical characterization, strain CY-GT represents a novel species of the genus Cytobacillus, for which the name Cytobacillus spongiae sp. nov. is proposed. The type strain is CY-GT (=MCCC 1K06383T=KCTC 43348T).

Identification and characterization of biocontrol agent Lysinibacillus boronitolerans P42 against Cerrena unicolor that causes root rot of arecanut palm.

The arecanut palm is one of the most important industrial crops in tropical area around the world. The root rot of arecanut palm, which is caused by Cerrena unicolor, has led to heavy economic losses and restricted greatly the development of arecanut industry, especially in Hainan province of China. The common use of chemical agents has worsened the problems of the emergence of resistant pathogens and the pollution of agricultural environment. This study aims to screen and identify a more effective and environment friendly biocontrol method for the prevention and treatment of root rot of arecanut palm. The mycelium growth rate is investigated to select antagonistic bacteria from tropical crop rotation fields which show improved resistance against soil-borne pathogens, and the strain P42 is revealed with the strongest antagonistic effects (82.18%). Based on 16 s rDNA sequence analysis, the strain P42 is identified as Lysinibacillus boronitolerans. In vitro antimicrobial activity shows that the strain P42 exhibits broad-spectrum antagonistic activity against a wide variety of tropical agricultural fungal pathogens, including Cerrena unicolor, Magnaporthe oryzea, Botryodiplodia theobromae, Neoscytalidium dimidiatum, Thanatephorus cucumeris, Fusarium oxysporum, and Botrytis cinerea Per.. The antagonistic activity of the culture of P42 is tolerant to common proteases, longer storage time, and temperature range of 40-121 °C; and is significantly influenced by alkaline (7-9) and acidic (1-2) pH, as well as by ultraviolet ray treatment for more than 30 min. The investigation on the antagonistic activity of the crude extract of fermentation filtrate indicates that the active compounds might be lipopeptides, polyketones, or proteins. To our knowledge, this is the first report of L. boronitolerans as potential bio-reagents for controlling root rot of arecanut palm caused by Cerrena unicolor.

Anoxybacillus: an overview of a versatile genus with recent biotechnological applications.

The Bacillaceae family members are considered to be a good source of microbial factories for biotechnological processes. In contrast to Bacillus and Geobacillus, Anoxybacillus, which would be thermophilic and spore-forming group of bacteria, is a relatively new genus firstly proposed in the year of 2000. The development of thermostable microbial enzymes, waste management and bioremediation processes would be a crucial parameter in the industrial sectors. There has been increasing interest in Anoxybacillus strains for biotechnological applications. Therefore, various Anoxybacillus strains isolated from different habitats have been explored and identified for biotechnological and industrial purposes such as enzyme production, bioremediation and biodegradation of toxic compounds. Certain strains have ability to produce exopolysaccharides possessing biological activities including antimicrobial, antioxidant and anticancer. This current review provides past and recent discoveries regarding Anoxybacillus strains and their potential biotechnological applications in enzyme industry, environmental processes and medicine.

Metabacillus arenae sp. nov., isolated from seashore sand.

A Gram-stain-positive, non-motile, rod-shaped, facultatively anaerobic bacterium, designated as IB182487T, was isolated from a seashore sand sample collected from Zhaoshu Island, PR China. Strain IB182487T grew at pH 6.0-10.0 (optimum, pH 8.0), 4-45 °C (optimum, 25-30 °C) and with 0-17 % (w/v) NaCl (optimum, 2-10 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain IB182487T belonged to the genus Metabacillus and was closely related to Metabacillus idriensis SMC 4352-2T, (96.6 %), Metabacillus indicus LMG 22858T (96.5 %), Metabacillus niabensis DSM 17723T (96.3 %) and Metabacillus halosaccharovorans DSM 25387T (96.1 %). Strain IB182487T had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan and contained menaquinone MK-7 as the predominant isoprenoid quinone. Its polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and three unidentified glycolipids. The major cellular fatty acids of strain IB182487T were iso-C15 : 0 and anteiso-C15 : 0. The whole genome average nucleotide identity and digital DNA-DNA hybridization analysis between the isolate and its closely related type strains demonstrated that the strain significantly differed from other Metabacillus species. The genomic DNA G+C content of strain IB182487T was 37.4 mol%. On the basis of phenotypic and chemotaxonomic properties, phylogenetic relatedness as well as genomic characteristics, strain IB182487T represents a novel species of the genus Metabacillus, for which the name Metabacillus arenae sp. nov. is proposed. The type strain of M. arenae is IB182487T (=MCCC 1K04629T=JCM 34523T).

Isolation and screening of chromium resistant bacteria from industrial waste for bioremediation purposes / Isolamento e triagem de bactérias resistentes ao cromo de resíduos industriais para fins de biorremediação

Chromium (VI) a highly toxic metal, a major constituent of industrial waste. It is continuously release in soil and water, causes environmental and health related issues, which is increasing public concern in developing countries like Pakistan. The basic aim of this study was isolation and screening of chromium resistant bacteria from industrial waste collected from Korangi and Lyari, Karachi (24˚52ʹ46.0ʺN 66˚59ʹ25.7ʺE and 24˚48ʹ37.5ʺN 67˚06ʹ52.6ʺE). Among total of 53 isolated strains, seven bacterial strains were selected through selective enrichment and identified on the basis of morphological and biochemical characteristics. These strains were designated as S11, S13, S17, S18, S30, S35 and S48, resistance was determined against varying concentrations of chromium (100-1500 mg/l). Two bacterial strains S35 and S48 showed maximum resistance to chromium (1600 mg/l). Bacterial strains S35 and S48 were identified through 16S rRNA sequence and showed 99% similarity to Bacillus paranthracis and Bacillus paramycoides. Furthermore, growth condition including temperature and pH were optimized for both bacterial strains, showed maximum growth at temperature 30ºC and at optimum pH 7.5 and 6.5 respectively. It is concluded that indigenous bacterial strains isolated from metal contaminated industrial effluent use their innate ability to transform toxic heavy metals to less or nontoxic form and can offer an effective tool for monitoring heavy metal contamination in the environment.

O cromo (VI), metal altamente tóxico, é um dos principais constituintes dos resíduos industriais. É liberado no solo e na água, causa problemas ambientais e de saúde de crescente preocupação pública em países em desenvolvimento como o Paquistão. O objetivo básico deste estudo foi o isolamento e a triagem de bactérias resistentes ao cromo de resíduos industriais coletados em Korangi e Lyari, Karachi (24˚52’46,0”N 66˚59’25,7”E e 24˚48’37,5”N 67˚06’52,6”E). Do total de 53 cepas isoladas, sete cepas bacterianas foram selecionadas por enriquecimento seletivo e identificadas com base em características morfológicas e bioquímicas. Essas cepas foram designadas como S11, S13, S17, S18, S30, S35 e S48, apresentaram alta resistência aos metais contra concentrações variáveis (100-1500 mg / l) de cromo. Já as cepas S35 e S48 foram identificadas por meio da sequência 16S rRNA e apresentaram 99% de similaridade com Bacillus paranthracis e Bacillus paramycoides. Além disso, as condições de crescimento incluindo temperatura e pH foram otimizadas e ambas as cepas bacterianas apresentaram crescimento máximo na temperatura de 30ºC, enquanto seu pH ótimo foi observado em 7,5 e 6,5, respectivamente. Conclui-se que o potencial de resistência dessas bactérias resistentes ao cromo pode ser efetivamente utilizado na remoção de cromo de efluentes industriais contaminados. Técnicas de base biológica usando bactérias ajudarão a fornecer métodos mais baratos e ecológicos de remoção, recuperação e desintoxicação de cromo.

Neobacillus rhizosphaerae sp. nov., isolated from the rhizosphere, and reclassification of Bacillus dielmonensis as Neobacillus dielmonensis comb. nov.

A Gram-stain-positive, facultative anaerobic endospore-forming bacterium, which originated from roots/rhizosphere of maize (Zea mays), was investigated for its taxonomic position. On the basis of 16S rRNA gene sequence similarities, strain JJ-3T was grouped together with Neobacillus species showing the highest similarities to Neobacillus bataviensis (98.8 %) and the three species Neobacillus dendrensis, Neobacillus soli and Neobacillus cucumis (all 98.6 %). The 16S rRNA gene sequence similarities to the sequences of the type strains of other Neobacillus species were lower than 98.5 %. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between the JJ-3T genome assembly and those of the other Neobacillus type strains were <83, <85 and <27 %, respectively. Chemotaxonomic features supported the grouping of the strain to the genus Neobacillus, e.g. the major fatty acids were C15 : 0 anteiso and C15 : 0 iso, the polar lipid profile contained the major components diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine, and the major quinone was menaquinone MK-7. Physiological and biochemical test results were slightly different from those of the most closely related species. For this reason, JJ-3T represents a novel species of the genus Neobacillus, for which we propose the name Neobacillus rhizosphaerae sp. nov., with JJ-3T (= CIP 111895T=LMG 32087T=DSM 111784T=CCM 9084T) as the type strain. We also propose to reclassify Bacillus dielmonensis as Neobacillus dielmonensis comb. nov. based mainly on the results of phylogenomic and conserved signature indel analyses.

Draft genome sequence and functional analysis of Lysinibacillus xylanilyticus t26, a plant growth-promoting bacterium isolated from Capsicum chinense rhizosphere.

Capsicum chinense is the chilli species containing the highest amount of capsaicin, and is an important traditional spice crop of Northeast India. Capsaicinoids derived from C. chinense are used in anticancer and anti-obesity treatments, as temperature regulators, in pain therapy, and as antioxidants. The current production and yield are very low due to the lack of organized cultivation and scientific inputs, and various plant diseases. Synthetic pesticides are frequently applied to boost yields, which creates potential risks to the environment, crops, and humans. The use of plant growth-promoting rhizobacteria is an alternative strategy in crop disease management to reduce the dependency on agrochemicals, which have detrimental effects on the environment. Lysinibacillus xylanilyticus t26 isolated from the C. chinense rhizosphere has shown good prospects in plant growth promotion and biocontrol. It showed strong antagonistic activity against Pythium ultimum ITCC 1650, Rhizoctonia solani ITCC 6491, and Fusarium oxysporum ITCC 6246. The draft genome sequencing of L. xylanilyticus t26 yielded a total of 5.69 Mbp with a G+C content of 36.80%. Genome analysis revealed that L. xylanilyticus t26 is very similar to L. xylanilyticus MH683160.1, and is phylogenetically related to L. xylanilyticus IBBPo7. Bioinformatics analysis predicted that it harbored type III polyketides, non-ribosomal peptides, terpenes, and lantibiotics including cerecidin, bacteriocins, siderophores, and thiopeptides, which are important traits of rhizobacteria for the utilization of minerals and to compete with other microbes for food. The strain t26 is a potential biocontrol agent for soil-borne fungal diseases. In this study, we derived the possible siderophore production pathways through the analysis of L. xylanilyticus t26 draft genome and plant growth response bioassays. The availability of genome data provides information that this draft genome harbored a siderophore BGC, which is 33% similar to petrobactin.

Sutcliffiella rhizosphaerae sp. nov. isolated from roots.

An aerobic, Gram-staining-positive, endospore-forming bacterium, isolated from the rhizosphere of roots of maize (Zea mays), was taxonomically studied. On the basis of 16S rRNA gene sequence similarity comparisons, strain JJ-125T clustered together with species of the genus Sutcliffiella and showed the highest similarities with Sutcliffiella zhanjiangensis (98.7 %). The 16S rRNA gene sequence similarities to the sequences of the type strains of other species of the genus Sutcliffiella were <98.4 %. The genome sequence of JJ-125T was 4 516 360 bp long and had a DNA G+C content of 37.3 %. A DNA-DNA hybridization with the type strain of S. zhanjiangensis DSM 23010T resulted in values of 42.3 and 43.9 % (reciprocal). The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between the JJ-125T genome assembly and those of the other type strains of species of the genus Sutcliffiella were <75%, <80 % and <21 %, respectively. Chemotaxonomic features supported the grouping of the strain with the genus Sutcliffiella, e.g. the major fatty acids included iso-C15 : 0, iso-C17 : 1 ω10c and iso-C17 : 0, the polar lipid profile contained the major components diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine, the only quinone was menaquinone MK-7 and the characteristic diamino acid was meso-diaminopimelic acid. Physiological and biochemical test results were also different from those of the most closely related species. As a consequence, JJ-125T represents a novel species of the genus Sutcliffiella, for which we propose the name Sutcliffiella rhizosphaerae sp. nov., with JJ-125T (= CIP 111883T = LMG 32156T = CCM 9046T) as the type strain.

Molecular study on recombinant cold-adapted, detergent- and alkali stable esterase (EstRag) from Lysinibacillus sp.: a member of family VI.

Cold-adapted esterases have potential industrial applications. To fulfil the global continuous demand for these enzymes, a cold-adapted esterase member of family VI from Lysinibacillus sp. YS11 was cloned on pET-28b (+) vector and expressed in E. coli BL21(DE3) Rosetta cells for the first time. The open reading frame (654 bp: GenBank MT120818.1) encodes a polypeptide (designated EstRag: 217 amino acid residues). EstRag amino acid sequence has conserved esterase signature motifs: pentapeptide (GFSQG) and catalytic triad Ser110-Asp163-His194. EstRag 3D predicted model, built with LOMETS3 program, showed closest structural similarity to PDB 1AUO_A (esterase: Pseudomonas fluorescens); TM-align score program inferences. Purified EstRag to 9.28-fold, using Ni2+affinity agarose matrix, showed a single protein band (25 kDa) on SDS-PAGE, Km (0.031 mM) and Kcat/Km (657.7 s-1 mM-1) on p-NP-C2. Temperature and pH optima of EstRag were 35 °C and 8.0, respectively. EstRag was fully stable at 5-30 °C for 120 min and at pH(s) 8.0-10.0 after 24 h. EstRag activity (391.46 ± 0.009%) was impressively enhanced after 30 min preincubation with 5 mM Cu2+. EstRag retained full stability after 30 min pre-incubation with 0.1%(v/v) SDS, Triton X-100, and Tween-80. EstRag promising characteristics motivate performing guided evolution and industrial applications prospective studies.

Oceanobacillus saliphilus sp. nov., Isolated from Saline-Alkali Soil in Heilongjiang Province, China.

A novel bacterium, designated strain APA_H-1(4)T, was isolated from the saline-alkaline soil, Zhaodong, Heilongjiang Province, China. Phenotypic and chemotaxonomic analyses, and whole-genome sequencing were used to determine the taxonomic position of the strain. Phylogenetic analysis indicated that the isolate belongs to the genus Oceanobacillus, and showed the highest sequence similarity to O. damuensis KCTC 33146T (98.35%, similarity) and 'O. massiliensis' DSM 24644 (98.32%). The average nucleotide identity values between strain APA_H-1(4)T and other members of the genus Oceanobacillus were lower than 82% recommended for distinguishing novel prokaryotic species. The digital DNA-DNA hybridization values of strain APA_H-1(4)T with O. damuensis KCTC 33146T and 'O. massiliensis' DSM 24644 were 13.60 and 17.60%, respectively. Cells of strain APA_H-1(4)T were Gram-staining positive, motile, aerobic, spore-forming rods (0.5-0.7 × 1.8-2.6 µm) with flagella. The growth was found to occur optimally at 37 °C. The whole-cell hydrolysate contained meso-diaminopimelic acid as the diagnostic cell wall diamino acid. The main detected polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and an unidentified polar lipid. The predominant respiratory quinone was identified as menaquinone-7 (MK-7). The major cellular fatty acid (>10%) was anteiso-C15:0. The G + C content of the genomic DNA was determined to be 38.4% based on the draft genome sequence. Based on the comparative analysis of polyphasic taxonomic data, strain APA_H-1(4)T represents a novel species of the genus Oceanobacillus, for which the name Oceanobacillus saliphilus sp. nov. is proposed. The type strain is APA_H-1(4)T (=GDMCC 1.2239T = KCTC 43254T).

Metabacillus kandeliae sp. nov., isolated from the rhizosphere soil of a decayed mangrove plant Kandelia candel.

In this study, we isolated a novel Gram-stain-positive, aerobic, motile, rod-shaped bacterium, named GX 13764T, from the rhizosphere soil of a decayed mangrove plant Kandelia candel collected from Beihai, Guangxi, PR China, and characterized using a polyphasic taxonomic approach. The strain exhibited yellow-orange, round, convex, shiny, smooth, opaque and 2-3 mm diameter colonies on marine agar 2216 media after 3 days of incubation at 30 °C and was capable of growth at 4-45 °C (optimum, 30 °C), pH 5.0-9.0 (optimum, pH 7.0) and 0-4 % NaCl (w/v; optimum, 2 %). The strain was positive for catalase and negative for the oxidase. The main cellular fatty acid was anteiso-C15:0, iso-C15:0, iso-C16:0 and iso-C14:0. The cell-wall peptidoglycan comprised meso-diaminopimelic acid and the main menaquinone was MK-7. The polar lipids included one diphosphatidylglycerol, one phosphatidylglycerol, two glycolipids, two unidentified phospholipids and three unidentified lipids. Based on 16S rRNA gene analysis, GX 13764T presented the highest sequence similarity to Metabacillus mangrovi KCTC 33872T (97.04 %). The DNA G+C content of the type strain was 44.2 mol%. The average nucleotide identity values between GX 13764T and M. mangrovi KCTC 33872T, Metabacillus idriensis DSM 19097T and Metabacillus indicus LMG 22858T were 69.39, 68.87 and 68.95 %, respectively, with digital DNA-DNA hybridization values of 19.9, 19.5 and 19.5 %, respectively. Based on the polyphasic data, strain GX 13764T should be nominated as a novel species of the genus Metabacillus, for which the name Metabacillus kandeliae sp. nov. is proposed. The type strain is GX 13764T (=MCCC 1K06654T=KCTC 43366T).

Pseudoneobacillus rhizosphaerae gen. nov., sp. nov., isolated from maize root rhizosphere.

A facultative anaerobic, Gram-stain-positive, endospore-forming bacterium, isolated from the rhizosphere of maize roots (Zea mays), was taxonomically studied. Based on 16S rRNA gene sequence similarity comparisons, strain JJ-79T clustered only loosely with Neobacillus species and showed the highest similarity to Neobacillus soli (97.9%). The 16S rRNA gene sequence similarities to the sequences of the type strains of other Neobacillus species were 97.5 % and below. Chemotaxonomic features supported the grouping of the strain to the Neobacillus group, e.g. the major fatty acids were C15 : 0 anteiso, C15 : 0 iso and C16 : 0, the polar lipid profile contained the major components diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified glycolipid, the major quinone was menaquinone MK-7, and major compound in the polyamine pattern was spermidine. However, the JJ-79T genome assembly did not share most of the 11 conserved signature indels that are indicative of the genus Neobacillus. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between the JJ-79T genome assembly and those of the closest relative Bacillaceae type strains were <71, <71 and <25 %, respectively. Physiological and biochemical test results were also different from those of the most closely related Bacillaceae species. As a consequence, JJ-79T represents a novel genus for which we propose the name Pseudoneobacillus rhizosphaerae gen. nov., sp. nov., with JJ-79T (=CIP 111885T=CCM 9045T) as the type strain.

Alteribacter keqinensis sp. nov., a moderately halophilic bacterium isolated from a soda lake.

A Gram-stain-positive, aerobic, endospore-forming and rod-shaped bacterium (KQ-3T), which grew at 10-45 °C (optimum 35 °C), pH 8.0-10.5 (optimum pH 9.0) and in the presence of 0-16 % (w/v) NaCl (optimum 3.0 %), was isolated from a soda lake and identified as representing a novel species using a polyphasic taxonomic approach. Strain KQ-3T was catalase-positive, oxidase-negative and non-motile. Phylogenetic analysis based on 16S rRNA gene sequence affiliated KQ-3T to the genus Alteribacter and showed the highest similarities to Alteribacter natronophilus M30T (97.90 %), Alteribacter aurantiacus K1-5T (97.84 %) and Alteribacter populi FJAT-45347T (97.22 %). Digital DNA-DNA hybridization and average nucleotide identity analyses revealed that KQ-3T displayed 21.4 and 72.81% genomic DNA relatedness with the most closely related strain, A. natronophilus M30T, respectively. KQ-3T contained all of the conserved signature indels that are specific for members of the genus Alteribacter. The DNA G+C content was 45.03 mol%. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the polar lipids consisted of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and one unidentified phospholipid. The predominant menaquinone was MK-7 (100%) and the major fatty acids (>10 %) comprised anteiso-C15 : 0, iso-C15 : 0 and iso-C16 : 0. Based on the data from the current polyphasic studies, KQ-3T represents a novel species of the genus Alteribacter, for which the name Alteribacter keqinensis sp. nov. is proposed. The type strain is KQ-3T (=ACCC 61799T=KCTC 33933T).

Neobacillus kokaensis sp. nov., isolated from soil.

A Gram-stain-variable, motile, aerobic, spore-forming, rod-shaped bacterium, designated as strain LOB 377T, was isolated from soil sampled in Koka County (now Konan City), in Shiga Prefecture, Japan. To determine its taxonomic position, the bacterium was evaluated by a polyphasic approach based on genomic, phenotypic and chemotaxonomic tests. From phylogenetic analysis based on 16S rRNA gene sequences, strain LOB 377T (LC570960) was revealed to have the highest similarity to the type strain of Neobacillus mesonae FJAT-13985T (9.1 %). The average nucleotide identity and digital DNA-DNA hybridization values between both strains based on whole genome sequences were 84.1 and 42.8 %, respectively, which were below the recommended thresholds. The strain grew at 15-45 °C (optimum, 25-37 °C), at pH 5.5-9.5 (optimum, pH 6.5-8.5) and with 1.0-2.0 % (w/v) NaCl. Cell-wall peptidoglycan of the strain contained meso-diaminopimelic acid. The major menaquinone was menaquinone-7. Predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C14 : 0 and C16 : 1 ω11c. The polar lipids were phosphatidylglycerol, unidentified phospholipid and unidentified aminophospholipid. The DNA G+C content was 40.5 mol%. According to the genomic, phenotypic and chemotaxonomic results, strain LOB 377T represents a novel species in the genus Neobacillus, for which the name Neobacillus kokaensis sp. nov. is proposed. The type strain is LOB 377T (=ATCC 31382T=NBRC 114637T=DSM 113418T).