Bacillus litoralis sp. nov., isolated from a tidal flat of the Yellow Sea in Korea

Complete Genome Sequence of Metabacillus litoralis Strain NCTR108, Isolated from Commercial Tattoo Ink

Metabacillus litoralis is part of the newly proposed genus Metabacillus. The bacterium was first isolated from a Yellow Sea tidal flat in 2005. As of May 2022, there are five genomic assemblies deposited in GenBank. We report the 5.2-Mbp genome sequence of M. litoralis strain NCTR108, from commercial tattoo ink.

Genomic and Physiological Characterization of Metabacillus flavus sp. nov., a Novel Carotenoid-Producing Bacilli Isolated from Korean Marine Mud

The newly isolated strain KIGAM252^T was found to be facultatively anaerobic, Gram-stain-positive, spore-forming, and rod-shaped. They grew at 10–45 °C, pH 6.0–10.0, and were able to tolerate up to 6% NaCl in the growth medium. Phylogenetic analysis indicated that the KIGAM252^T strain was related to the genus Metabacillus. The cell membrane fatty acid composition of strain KIGAM252^T included C_15:0 anteiso and C_15:0 iso (25.6%) as the major fatty acids, and menaquinone 7 was the predominant isoprenoid quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The size of the whole genome was 4.30 Mbp, and the G + C content of the DNA was 43.8%. Average nucleotide and amino acid identity and in silico DNA-DNA hybridization values were below the species delineation threshold. Pan-genomic analysis revealed that 15.8% of all genes present in strain KIGAM252^T was unique to the strain. The analysis of the secondary biosynthetic pathway predicted the carotenoid synthetic gene cluster in the strain KIGAM252^T. Based on these current polyphasic taxonomic data, strain KIGAM252^T represents a novel species of the genus Metabacillus that produces carotenoids, for which we propose the name Metabacillus flavus sp. nov. The type of strain was KIGAM252^T (=KCTC 43261^T = JCM 34406^T).

Metabacillus bambusae sp. nov., isolated from bamboo grove soil

A bacterial strain designated BG109T was isolated from bamboo grove soil, and subjected to polyphasic taxonomic characterization. BG109T is an aerobic, non-motile, Gram-stain-positive and endospore-forming bacterium. BG109T showed growth at 10–40 °C (optimum, 37 °C), at pH 4–10 (optimum, 8), and in the presence of 0–7 % NaCl concentration (optimum, 0–1 %). The predominant menaquinone of BG109T was MK-7, and the cell wall peptidoglycan contained major amounts of meso–diaminopimelic acid as the diagnostic diamino acid. The diagnostic polar lipids were diphosphatidylglycerol and phosphatidylglycerol, and unidentified phospholipids and glycolipids were also present. The major fatty acids were anteiso-C15 : 0, iso-C15 : 0, iso-C14 : 0, iso-C16 : 0 and C16 : 0. The chemotaxonomic properties of BG109T were generally consistent with those of members of the genus Metabacillus . BG109T shared highest 16S rRNA gene sequence similarities with ‘Metabacillus elymi’ KUDC1714 (99.26 %), Metabacillus sediminilitoris DSL-17T (98.17 %), Metabacillus litoralis SW-211T (98.16 %) and Metabacillus crassostreae JSM 100118T (97.13 %), all of which were well below the suggested cutoff level for species distinction. The genome level relatedness also confirmed the separation of BG109T from other species of the genus Metabacillus . Thus, it is evident that BG109T merits recognition as representing a novel species of the genus Metabacillus , for which the name Metabacillus bambusae sp. nov. is proposed. The type strain is BG109T (=KCTC 43190T=JCM 34515T).

Metabacillus elymi sp. nov., isolated from the Rhizosphere of Elymus tsukushiensis, a plant native to the Dokdo Islands, Republic of Korea

Dokdo islands in Republic of Korea, is not suited to survive plant because strong wind, low organic content and high salinity. Nevertheless, 64 taxa of plants have a symbiotic relationship with microbe. The Metabacillus elymi KUDC1714^T was isolated from the rhizosphere of Elymus tsukushiensis collected from Dokdo Islands. This bacterial strain was Gram-stain positive, non-motile, non-spore forming, aerobic and rod-shape bacteria with 0.4-0.5 × 2.5-3.0 μm in size. Colonies were smooth, yellowish-white circular and 2.0-3.0 mm in diameter. KUDC1714^T was capable of growing at 10-45 °C (optimum, 30 °C), pH 7-11 (optimum, pH 8) and 0-8.0% (w/v) NaCl (optimum, 1.0-2.0%). Flagella were not observed by transmission electron microscopy. Phylogenetic analyses, based on 16S rRNA gene sequences, showed that KUDC1714^T belonged to the genus Metabacillus formed a phyletic lineage within the genus Metabacillus of the family Bacillaceae. The strain KUDC1714^T was most closely related to Metabacillus sediminilitoris DSL-17 ^T (98.2%), Metabacillus litoralis SW-211 ^T (98.2%) and Metabacillus halosaccharovorans E33^T (97.7%) based on 16S rRNA gene sequence. In silico DNA-DNA hybridization using genome-to-genome distance calculator were analysed at 25.8% and 23.5% in strain KUDC1714^T and Metabacillus sediminilitoris DSL-17 ^T, and strain KUDC1714^T and Metabacillus litoralis SW-211 ^T, respectively. Strain KUDC1714^T and its closet type strain were all below cut-off point of the average nucleotide identity and average amino acid identity values. The genome contains 5197 CDSs, 3 rRNAs, 118 tRNAs, 5 ncRNAs. The genomic DNA G + C content was 34.8 mol%. Its polar lipids were diphosphatidylglycerol, phosphatidylglycerol and its major fatty acids were anteiso-C_15:0 and iso-C_15:0. The strain KUDC1714^T contained menaquinone-7 as major isoprenoid quinone. Based on its genetic data, physiological and biochemical characteristics, strain KUDC1714^T should be considered a novel species of the genus Metabacillus, for which we propose the name Metabacillus elymi sp. nov. the type strain is KUDC1714^T (= KCTC 33222 ^T, = DSM 27608 ^T).

Metabacillus schmidteae sp. nov., Cultivated from Planarian Schmidtea mediterranea Microbiota

Taxonogenomics combines phenotypic assays and genomic analysis as a means of characterizing novel strains. We used this strategy to study Marseille-P9898T strain, an aerobic, motile, Gram-negative, spore-forming, and rod-shaped bacterium isolated from planarian Schmidtea mediterranea. Marseille-P9898T is catalase-positive and oxidase-negative. The major fatty acids detected are 12-methyl-tetradecanoic acid, 13-methyl-tetradecanoic acid, and hexadecanoic acid. Marseille-P9898T strain shared more than 98% sequence similarity with the Metabacillus niabensis strain 4T19T (98.99%), Metabacillus halosaccharovorans strain E33T (98.75%), Metabacillus malikii strain NCCP-662T (98.19%), and Metabacillus litoralis strain SW-211T (97.15%). Marseille-P9898 strain belongs to Metabacillus genus. Genomic analysis revealed the highest similarities with Ortho-ANI and dDDH, 85.76% with Metabacillus halosaccharovorans, and 34.20% with Bacillus acidicola, respectively. These results show that the Marseille-P9898T strain is a novel bacterial species from Metabacillus genus, for which we propose the name of Metabacillus schmidteae sp. nov. (Type strain Marseille-P9898T = CSUR P9898T = DSM 111480T).

Metabacillus sediminilitoris sp. nov., a marine bacterium isolated from a tidal sediment

A Gram-stain-positive, endospore-forming, motile and rod-shaped bacterium, designated as strain DSL-17^T, was isolated from a tidal sediment of the East China Sea and characterized phylogenetically and phenotypically. The strain could grow at 16-47 °C (optimum 37 °C), at pH 6.0-10.0 (optimum 6.0) and with 1-7% (w/v) NaCl (optimum 3 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain DSL-17^T was related to members of the genus Metabacillus and shared the highest similarity with Metabacillus litoralis SW-211^T (98.6 %), followed by Metabacillus halosaccharovorans E33^T (97.9 %), Metabacillus crassostreae JSM 100118^T (97.7 %), Metabacillus niabensis 4T19^T (97.7 %) and Metabacillus malikii NCCP-662^T (97.5 %). 16S rRNA gene sequence similarities between strain DSL-17^T and other members of the genus Metabacillus were below 96.6 %. The sole respiratory quinone was MK-7. Strain DSL-17^T had a cell-wall peptidoglycan based on meso-diaminopimelic acid. The polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), three unidentified glycolipids and six unidentified lipids. The strain had iso-C_15 : 0, anteiso-C_15 : 0, iso-C_14 : 0, C_16 : 0 and iso-C_16 : 0 as major fatty acids. The G+C content of the genomic DNA was 35.7 mol%. The combined genotypic and phenotypic data indicated that strain DSL-17^T represents a novel species of the genus Metabacillus, for which the name Metabacillus sediminilitoris sp. nov. is proposed The type strain is DSL-17^T (=MCCC 1K03777^T=DSM 109843^T).

A phylogenomic and comparative genomic framework for resolving the polyphyly of the genus Bacillus: Proposal for six new genera of Bacillus species, Peribacillus gen. nov., Cytobacillus gen. nov., Mesobacillus gen. nov., Neobacillus gen. nov., Metabacillus gen. nov. and Alkalihalobacillus gen. nov

The genus Bacillus, harbouring 293 species/subspecies, constitutes a phylogenetically incoherent group. In the absence of reliable means for grouping known Bacillus species into distinct clades, restricting the placement of new species into this genus has proven difficult. To clarify the evolutionary relationships among Bacillus species, 352 available genome sequences from the family Bacillaceae were used to perform comprehensive phylogenomic and comparative genomic analyses. Four phylogenetic trees were reconstructed based on multiple datasets of proteins including 1172 core Bacillaceae proteins, 87 proteins conserved within the phylum Firmicutes, GyrA-GyrB-RpoB-RpoC proteins, and UvrD-PolA proteins. All trees exhibited nearly identical branching of Bacillus species and consistently displayed six novel monophyletic clades encompassing 5-23 Bacillus species (denoted as the Simplex, Firmus, Jeotgali, Niacini, Fastidiosus and Alcalophilus clades), interspersed with other Bacillaceae species. Species from these clades also generally grouped together in 16S rRNA gene trees. In parallel, our comparative genomic analyses of Bacillus species led to the identification of 36 molecular markers comprising conserved signature indels in protein sequences that are specifically shared by the species from these six observed clades, thus reliably demarcating these clades based on multiple molecular synapomorphies. Based on the strong evidence from multiple lines of investigations supporting the existence of these six distinct 'Bacillus' clades, we propose the transfer of species from these clades into six novel Bacillaceae genera viz. Peribacillus gen. nov., Cytobacillus gen. nov., Mesobacillus gen. nov., Neobacillus gen. nov., Metabacillus gen. nov. and Alkalihalobacillus gen. nov. These results represent an important step towards clarifying the phylogeny/taxonomy of the genus Bacillus.

Comparative genomics study reveals Red Sea Bacillus with characteristics associated with potential microbial cell factories (MCFs)

Recent advancements in the use of microbial cells for scalable production of industrial enzymes encourage exploring new environments for efficient microbial cell factories (MCFs). Here, through a comparison study, ten newly sequenced Bacillus species, isolated from the Rabigh Harbor Lagoon on the Red Sea shoreline, were evaluated for their potential use as MCFs. Phylogenetic analysis of 40 representative genomes with phylogenetic relevance, including the ten Red Sea species, showed that the Red Sea species come from several colonization events and are not the result of a single colonization followed by speciation. Moreover, clustering reactions in reconstruct metabolic networks of these Bacillus species revealed that three metabolic clades do not fit the phylogenetic tree, a sign of convergent evolution of the metabolism of these species in response to special environmental adaptation. We further showed Red Sea strains Bacillus paralicheniformis (Bac48) and B. halosaccharovorans (Bac94) had twice as much secreted proteins than the model strain B. subtilis 168. Also, Bac94 was enriched with genes associated with the Tat and Sec protein secretion system and Bac48 has a hybrid PKS/NRPS cluster that is part of a horizontally transferred genomic region. These properties collectively hint towards the potential use of Red Sea Bacillus as efficient protein secreting microbial hosts, and that this characteristic of these strains may be a consequence of the unique ecological features of the isolation environment.

Aeolian transport of viable microbial life across the Atacama Desert, Chile: Implications for Mars

Here we inspect whether microbial life may disperse using dust transported by wind in the Atacama Desert in northern Chile, a well-known Mars analog model. By setting a simple experiment across the hyperarid core of the Atacama we found that a number of viable bacteria and fungi are in fact able to traverse the driest and most UV irradiated desert on Earth unscathed using wind-transported dust, particularly in the later afternoon hours. This finding suggests that microbial life on Mars, extant or past, may have similarly benefited from aeolian transport to move across the planet and find suitable habitats to thrive and evolve.

Isolation of a novel alginate lyase-producing Bacillus litoralis strain and its potential to ferment Sargassum horneri for biofertilizer

Algae have long been used to augment plant productivity through their beneficial effects. Alginate oligosaccharide is believed to be one of the important components to enhance growth and crop yield. In this study, we isolated and characterized a Bacillus litoralis strain, named Bacillus M3, from decayed kelps. We further demonstrated that the M3 strain could secrete alginate lyase to degrade alginate. The crude enzyme exhibited the highest activity (33.74 U/mg) at pH 7.0 and 50°C. The M3 strain was also able to ferment the brown alga Sargassum horneri. Fermentation results revealed that a fermentation period of 8-12 hr was the best harvest time with the highest level of alginate oligosaccharides. Plant growth assay showed that the seaweed fermentation extract had an obvious promotion effect on root and seedling growth of Lycopersicon eseulentum L. Our results suggest that fermentation extract of Sargassum horneri by the novel strain of Bacillus litoralis M3 has significant development potential for biofertilizer production and agriculture application.

Draft Genome Sequence of Bacillus litoralis C44, Isolated from Chinese Scholar Tree (Sophora japonica) Forest Soil

Bacillus litoralis C44 can hydrolyze rutin to produce isoquercetin by the enzyme α-l-rhamnosidase. We report here the genome sequence and annotation result of strain C44. The genomic information will serve as references to the physiology, genetics, and evolution of this species and further genetic engineering research in this species.

Surfactant-associated bacteria in the near-surface layer of the ocean

Certain marine bacteria found in the near-surface layer of the ocean are expected to play important roles in the production and decay of surface active materials; however, the details of these processes are still unclear. Here we provide evidence supporting connection between the presence of surfactant-associated bacteria in the near-surface layer of the ocean, slicks on the sea surface, and a distinctive feature in the synthetic aperture radar (SAR) imagery of the sea surface. From DNA analyses of the in situ samples using pyrosequencing technology, we found the highest abundance of surfactant-associated bacterial taxa in the near-surface layer below the slick. Our study suggests that production of surfactants by marine bacteria takes place in the organic-rich areas of the water column. Produced surfactants can then be transported to the sea surface and form slicks when certain physical conditions are met. This finding has potential applications in monitoring organic materials in the water column using remote sensing techniques. Identifying a connection between marine bacteria and production of natural surfactants may provide a better understanding of the global picture of biophysical processes at the boundary between the ocean and atmosphere, air-sea exchange of greenhouse gases, and production of climate-active marine aerosols.

Bacillus crassostreae sp. nov., isolated from an oyster (Crassostrea hongkongensis)

A novel Gram-stain-positive, motile, catalase- and oxidase-positive, endospore-forming, facultatively anaerobic rod, designated strain JSM 100118(T), was isolated from an oyster (Crassostrea hongkongensis) collected from the tidal flat of Naozhou Island in the South China Sea. Strain JSM 100118(T) was able to grow with 0-13% (w/v) NaCl (optimum 2-5%), at pH 5.5-10.0 (optimum pH 7.5) and at 5-50 °C (optimum 30-35 °C). The cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The predominant respiratory quinone was menaquinone-7 and the major cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0, C16 : 0 and C16 : 1ω11c. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unknown glycolipid and an unknown phospholipid. The genomic DNA G+C content was 35.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain JSM 100118(T) belonged to the genus Bacillus , and was most closely related to Bacillus litoralis SW-211(T) (98.9% 16S rRNA gene sequence similarity), Bacillus halosaccharovorans E33(T) (98.3%), Bacillus niabensis 4T19(T) (97.8%) and Bacillus herbersteinensis D-1,5a(T) (97.1%). The combination of results from the phylogenetic analysis, DNA-DNA hybridization, and phenotypic and chemotaxonomic characterization supported the conclusion that strain JSM 100118(T) represents a novel species of the genus Bacillus , for which the name Bacillus crassostreae sp. nov. is proposed. The type strain is JSM 100118(T) ( = CTCC AB 2010452(T) =DSM 24486(T) =JCM 17523(T)).

Evolution in the Bacillaceae

The family Bacillaceae constitutes a phenotypically diverse and globally ubiquitous assemblage of bacteria. Investigation into how evolution has shaped, and continues to shape, this family has relied on several widely ranging approaches from classical taxonomy, ecological field studies, and evolution in soil microcosms to genomic-scale phylogenetics, laboratory, and directed evolution experiments. One unifying characteristic of the Bacillaceae , the endospore, poses unique challenges to answering questions regarding both the calculation of evolutionary rates and claims of extreme longevity in ancient environmental samples.

Bacillus cheonanensis sp. nov. isolated from near poultry farm soil [corrected]

A novel bacterial strain, designated PFS-5(T), was isolated from the soil environment with feces of a live poultry farm located in Cheonan, Republic of Korea. Strain PFS-5(T) was Gram-staining-positive, motile, strictly aerobic bacterium, rod-shaped, and endospore-forming. The strain contained meso-diaminopimelic acid in their peptidoglycan and MK-7 menaquinone. The major fatty acids were anteiso-C15:0 (44.2%), C16:0 (22.2%), and iso-C15:0 (16.7%). The DNA G+C content was 40.1 mol%. Comparative 16S rRNA gene sequence analysis identified strain PFS-5(T) in the genus Bacillus, exhibiting the highest level of sequence similarity with type strain of B. herbersteinensis D-1,5a(T) (96.9%), B. humi LMG 22167(T) (96.7%), B. alkalitelluris BA288(T) (96.1%), B. litoralis SW-211(T) (96.0%), and B. luteolus YIM93174(T) (95.5%). The major polar lipids of PFS-5(T) were diphosphatidylglycerol and phosphatidylglycerol. On the basis of result from poly-phasic data, strain PFS-5(T) represents a novel species, for which the name Bacillus cheonanensis sp. nov. is proposed (Type strai PFS-5(T) = KACC 17469(T) = JCM19333(T)).

Bacterial diversity of extremely alkaline bauxite residue site of alumina industrial plant using culturable bacteria and residue 16S rRNA gene clones

Bauxite residue (red mud), generated during the extraction of alumina from bauxite ore is characterized by high pH, high concentrations of soluble ions with low or virtually no organic matter. These extreme conditions along with numerous nutrient deficiencies, limit the microbial growth and vegetation establishment. In the present study, diversity of both cultivable and non-cultivable bacteria present in the red mud was investigated by 16S rDNA sequence analyses. The cultivable bacteria were identified as Agromyces indicus, Bacillus litoralis, B. anthracis, Chungangia koreensis, Kokuria flava, K. polaris, Microbacterium hominis, Planococcus plakortidis, Pseudomonas alcaliphila and Salinococcus roseus based on their 16S rDNA sequence analysis. These isolates were alkali tolerant, positive for one or more of the enzyme activities tested, able to produce organic acids and oxidize wide range of carbon substrates. For non-cultivable diversity of bacteria, DNA was extracted from the bauxite residue samples and 16S rDNA clone library was constructed. The 16S rDNA clones of this study showed affiliation to three major phyla predominant being betaproteobacteria (41.1%) followed by gammaproteobacteria (37.5%) and bacteroidetes (21.4%). We are reporting for the first time about the bacterial diversity of this unique and extreme environment.

Bacillus luteolus sp. nov., a halotolerant bacterium isolated from a salt field

A novel Gram-stain-positive, motile, strictly aerobic bacterium, designated YIM 93174T, was isolated from a salt field in Korea. Cells of this strain were rod-shaped and formed pale tangerine colonies and grew at pH 6.0–8.0 (optimal growth at pH 7.0), at 15–45 °C (optimum 28–37 °C) and at salinities of 0–10 % (w/v) NaCl (optimum 0–2 % NaCl). Some phenotypic characters allowed differentiation of strain YIM 93174T from its nearest phylogenetic relatives. Comparative 16S rRNA gene sequence analysis showed that strain YIM 93174T belongs to the genus Bacillus, exhibiting the highest level of sequence similarity with the type strain of Bacillus humi (95.7 %), followed by those of Bacillus alkalitelluris (94.9 %) and Bacillus litoralis (94.5 %). The major fatty acids were iso-C15 : 0, anteiso-C15 : 0 and iso-C16 : 0. The cell-wall peptidoglycan was of the A1γ type, containing meso-diaminopimelic acid as the diagnostic diamino acid. The genomic DNA G+C content was 36.9 mol% and the predominant respiratory quinone was MK-7. The major polar lipids of strain YIM 93174T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and two unknown phospholipids. On the basis of the evidence from this polyphasic study, strain YIM 93174T represents a novel species of the genus Bacillus, for which the name Bacillus luteolus sp. nov. is proposed, with YIM 93174T ( = DSM 22388T  = KCTC 13210T  = CCTCC AA 208068T) as the type strain.

The effect of feed salinity on the biofouling dynamics of seawater desalination

A persistent cell labeling dye and a novel microbial counting method were used to explore the effects of salinity on a microbial population in a reverse osmosis (RO) desalination system, and these clearly distinguished microbial cell multiplication from cell adherence. The results indicated that microbial multiplication is more active at the front of a seawater RO pressure vessel, while adhesion dominates the back of the vessel. A severe reduction in RO permeate flux and total dissolved solid (TDS) rejection were detected at low salinity, attributed to marked cell multiplication and release of extracellular polymeric substances, whilst a relatively stable flux was observed at medium and high salinity. The results from PCR-DGGE revealed the variation in microbial species distribution on the membrane with salinity. The results imply the critical role of membrane modification in biofouling mitigation in the desalination process.

Discovery of marine Bacillus species by 16S rRNA and rpoB comparisons and their usefulness for species identification

Systematic studies of the Bacillus group have been biased towards terrestrial and pathogenic isolates, and relatively few studies have examined Bacillus species from marine environments. Here we took twenty Bacillus strains from diverse marine environments and sequenced their 16S rRNA. Using molecular comparisons, we separated the strains into thirteen Bacillus genotypes and identified 9 species: B. aquaemaris. B. badius, B. cereus group, B. firmus, B. halmapalus, B. hwajinpoensis, B. litoralis, B. sporothermodurans, B. vietnamensis, and three indistinguishable Bacilli. In addition, we sequenced the DNA-directed RNA polymerase beta subunit (rpoB) gene and assessed its discriminative power in identifying Bacilli. Phylogenetic trees of Bacillus rpoB genes separated each Bacillus according to their taxonomic positions and were supported statistically. The resolution of Bacillus on the rpoB phylogenetic tree was approximately 4.5 times greater than on the 16S rRNA phylogenetic tree. These results demonstrate that the polymorphism of the Bacillus rpoB gene can be used to identify Bacillus species, providing an improved identification scheme for Bacillus species.

Bacillus coahuilensis sp. nov., a moderately halophilic species from a desiccation lagoon in the Cuatro Ciénegas Valley in Coahuila, Mexico

A moderately halophilic, Gram-positive and rod-shaped bacterium, strain m4-4T, was isolated from a Chihuahuan desert lagoon in Cuatro Ciénegas, Coahuila, Mexico. Strain m4-4T was found to grow optimally at 30-37 degrees C, pH 7.0-8.0 and 5 % NaCl and to tolerate from 0.5 % to 10 % NaCl. It was shown to be aerobic. The genomic DNA G+C content was about 37 mol%. Strain m4-4T exhibited minimal or no growth on most sugars tested. Its major cellular fatty acids were C14 : 0, C16 : 0 and C18 : 1. Based on phylogenetic analysis of 16S rRNA and recA gene sequences, we observed that the closest relatives of the isolate are moderately halophilic Bacillus species, with 16S rRNA gene sequence similarity ranging from 96.6 to 97.4 % (Bacillus marisflavi, Bacillus aquimaris and Bacillus vietnamensis). Additionally, using genomic data it was determined that the type strain contains a total of nine rRNA operons with three slightly different sequences. On the basis of phenotypic and molecular properties, strain m4-4T represents a novel species within the genus Bacillus, for which the name Bacillus coahuilensis sp. nov. is proposed, with the type strain m4-4T (=NRRL B-41737T =CECT 7197T).

Bacillus niabensis sp. nov., isolated from cotton-waste composts for mushroom cultivation

A group of five bacilli, designated strains 4T12, 4T19(T), 5M45, 5M53 and 5T52, isolated from cotton-waste composts for mushroom cultivation, were examined. These strains were Gram-positive, aerobic, motile, spore-forming rods. 16S rRNA gene sequence analyses revealed that the isolates belonged to the genus Bacillus, showing the highest levels of similarity (approx. 96.6-96.9 %) with respect to Bacillus herbersteinensis DSM 16534(T). The values for DNA-DNA hybridization (approx. 85-96 %) among these five strains revealed that they belong to the same species. The major menaquinone present was MK-7 and the predominant cellular fatty acids were anteiso-C(15 : 0) (approx. 24.5-33.9 %) and C(16 : 0) (approx. 15.1-34.1 %). The DNA G+C contents were 37.7-40.9 mol%. On the basis of physiological, biochemical, chemotaxonomic and comparative genomic analyses, the five isolates represent a novel species of the genus Bacillus, for which the name Bacillus niabensis sp. nov. is proposed. The type strain is 4T19(T) (=KACC 11279(T) =DSM 17723(T)).