RESUMO
An isolate of a Gram-positive, strictly aerobic, motile, rod-shaped, endospore forming bacterium was originally isolated from soil when screening and bioprospecting for plant beneficial microorganisms. Phylogenetic analysis of the 16S rRNA gene sequences indicated that this strain was closely related to Lysinibacillus fusiformis NRRL NRS-350T (99.7%) and Lysinibacillus sphaericus NRRL B-23268T (99.2%). In phenotypic characterization, the novel strain was found to grow between 10 and 45 °C and tolerate up to 8% (w/v) NaCl. Furthermore, the strain grew in media with pH 5 to 10 (optimal growth at pH 7.0). The predominant cellular fatty acids were observed to be iso-C15:â0 (52.3%), anteiso-C15:â0 (14.8%), C16:1ω7C alcohol (11.2%), and C16:â0 (9.5%). The cell-wall peptidoglycan contained lysine-aspartic acid, the same as congeners. A draft genome was assembled and the DNA G+C content was determined to be 37.1% (mol content). A phylogenomic analysis on the core genome of the new strain and 5 closest type strains of Lysinibacillus revealed this strain formed a distinct monophyletic clade with the nearest neighbor being Lysinibacillus fusiformis. DNA-DNA relatedness studies using in silico DNA-DNA hybridizations (DDH) showed this species was below the species threshold of 70%. Based upon the consensus of phylogenetic and phenotypic analyses, we conclude that this strain represents a novel species within the genus Lysinibacillus, for which the name Lysinibacillus pinottii sp. nov. is proposed, with type strain PB211T (= NRRL B-65672T, = CCUG 77181T).
Assuntos
Bacillaceae , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Filogenia , RNA Ribossômico 16S , Bacillaceae/genética , Bacillaceae/classificação , Bacillaceae/isolamento & purificação , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Peptidoglicano , Animais , Genoma Bacteriano , Análise de Sequência de DNA , Parede Celular/químicaRESUMO
Lysinibacillus is a bacterial genus that has generated recent interest for its biotechnological potential in agriculture. Strains belonging to this group are recognized for their mosquitocidal and bioremediation activity. However, in recent years some reports indicate its importance as plant growth promoting rhizobacteria (PGPR). This research sought to provide evidence of the PGP activity of Lysinibacillus spp. and the role of the indole-3-acetic acid (IAA) production associated with this activity. Twelve Lysinibacillus spp. strains were evaluated under greenhouse conditions, six of which increased the biomass and root architecture of corn plants. In most cases, growth stimulation was evident at 108 CFU/mL inoculum concentration. All strains produced IAA with high variation between them (20-70 µg/mL). The bioinformatic identification of predicted genes associated with IAA production allowed the detection of the indole pyruvic acid pathway to synthesize IAA in all strains; additionally, genes for a tryptamine pathway were detected in two strains. Extracellular filtrates from all strain's cultures increased the corn coleoptile length in an IAA-similar concentration pattern, which demonstrates the filtrates had an auxin-like effect on plant tissue. Five of the six strains that previously showed PGPR activity in corn also promoted the growth of Arabidopsis thaliana (col 0). These strains induced changes in root architecture of Arabidopsis mutant plants (aux1-7/axr4-2), the partial reversion of mutant phenotype indicated the role of IAA on plant growth. This work provided solid evidence of the association of Lysinibacillus spp. IAA production with their PGP activity, which constitutes a new approach for this genus. These elements contribute to the biotechnological exploration of this bacterial genus for agricultural biotechnology.
Assuntos
Arabidopsis , Bacillaceae , Ácidos Indolacéticos/metabolismo , Desenvolvimento Vegetal , Bactérias/metabolismo , Bacillaceae/genética , Bacillaceae/metabolismo , Arabidopsis/metabolismo , Plantas/metabolismo , Raízes de Plantas/microbiologiaRESUMO
A Gram-stain positive, aerobic, motile, rod-shaped bacterium designated as strain CBP-2801T was isolated as a contaminant from a culture containing maize callus in Peoria, Illinois, United States. The strain is unique relative to other Cohnella species due to its slow growth and reduced number of sole carbon sources. Phylogenetic analysis using 16S rRNA indicated that strain CBP-2801T is a Cohnella bacterium and showed the highest similarity to Cohnella xylanilytica (96.8%). Genome-based phylogeny and genomic comparisons based on average nucleotide identity confirmed the strain to be a novel species of Cohnella. Growth occurs at 15-45 °C (optimum 40 °C), pH 5-7 (optimum pH 6) and with 0-1% NaCl. The predominant fatty acids are anteiso-15:0 and 18:1 ω6c. Genome mining for secondary metabolites identified a putative biosynthetic cluster that encodes for a novel lasso peptide. In addition, this study contributes five new genome assemblies of type strains of Cohnella species, a genus with less than 30% of the type strains sequenced. The DNA G + C content is 58.7 mol %. Based on the phenotypic, phylogenetic and biochemical data strain CBP-2801T represents a novel species, for which the name Cohnella zeiphila sp. nov. is proposed. The type strain is CBP-2801T (= DSM 111598 = ATCC TSD-230).
Assuntos
Fosfolipídeos , Zea mays , Bacillales , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
We isolated a filamentous, thermophilic, and first anaerobic representative of the genus Thermoactinomyces, designated strain AMNI-1T, from a biogas plant in Tyrol, Austria and report the results of a phenotypic, genetic, and phylogenetic investigation. Strain AMNI-1T was observed to form a white branching mycelium that aggregates into pellets when grown in liquid medium. Cells could primarily utilize lactose, glucose, and mannose as carbon and energy sources, with acetate accelerating and yeast extract being mandatory for growth. The optimum growth temperature and pH turned out to be 55 °C and pH 7.0, respectively, with an optimum NaCl concentration of 0-2% (w/v). 16S rRNA gene sequence comparison indicated that the genetic relatedness between strain AMNI-1T and Thermoactinomyces intermedius, Thermoactinomyces khenchelensis, and Thermoactinomyces vulgaris was less than 97%. The G + C content of the genomic DNA was 44.7 mol%. The data obtained suggest that the isolate represents a novel and first anaerobic species of the genus Thermoactinomyces, for which the name Thermoactinomyces mirandus is proposed. The type strain is AMNI-1T (= DSM 110094T = LMG 31503T). The description of the genus Thermoactinomyces is emended accordingly.
Assuntos
Thermoactinomyces , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , Biocombustíveis , DNA Bacteriano/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Thermoactinomyces/genéticaRESUMO
KEY MESSAGE: Bacillus spizizenii is for the first time described as a plant growth salt-tolerant bacterium able to alleviate salt stress in crop plants by improving physiological parameters and antioxidant defense mechanisms. Agricultural soil salinization is a serious issue worldwide affecting agricultural yield. Plant growth promoting bacteria can enhance salt tolerance and plant yield. Bacillus spizizenii FMH45 has been shown to inhibit fungal attacks in tomato fruits and to augment tomato seed germination in presence of abiotic stresses. During this study, we reported for the first time B. spizizenii as a salt-tolerant bacterium able to alleviate salt stress in tomato plants. B. spizizenii FMH45 was examined in vitro for its potential to produce several plant growth promoting characters (siderophores, IAA, and phosphate solubilization) and hydrolytic enzymes (cellulase, glucanase and protease) in the presence of saline conditions. FMH45 was also investigated in vivo in pot experiments to evaluate its ability to promote tomato plant growth under salt stress condition. FMH45 inoculation, enhanced tomato seedling length, vigor index, and plant fresh and dry weights when compared to the non-inoculated controls exposed and not exposed to a regular irrigation with salt solutions containing: 0; 3.5; 7; and 10 g L-1 of NaCl. FMH45-treated plants also presented improved chlorophyll content, membrane integrity (MI), and phenol peroxidase (POX) concentrations, as well as reduced malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels under saline conditions with a significant salinity × strain interaction. Furthermore, FMH45 inoculation significantly decreased endogenous Na+ accumulation, increased K+ and Ca2+ uptake, and thereby improved K+/Na+ and Ca2+/Na+ ratios. This study proves that bio-inoculation of FMH45 efficiently increases salt tolerance in tomato plants. This sustainable approach can be applied to other stressed plant species in affected soils.
Assuntos
Inoculantes Agrícolas/fisiologia , Bacillus/fisiologia , Estresse Salino/fisiologia , Solanum lycopersicum/fisiologia , Antioxidantes/metabolismo , Carotenoides/metabolismo , Membrana Celular/metabolismo , Clorofila/metabolismo , Germinação , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Metais/metabolismo , Peroxidase/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/crescimento & desenvolvimentoRESUMO
The aim of this investigation was to isolate and identify Bacillus species isolated from the internal microbiota of Red sea stingrays as potential probiotics. An initial assay on the ability of the isolates to control stingray pathogens of Vibrio species led to the selection of one highly antagonistic isolate. The most potent isolate was identified based on whole genome phylogeny as Bacillus velezensis AMB-y1. Genome mining for secondary metabolites identified five antibacterial biosynthetic clusters that produce, bacilysin, bacillaene, difficidin, macrolactin and mersacidin. Genome mining also identified two antifungal biosynthetic clusters which encode genes to produce bacillomycin D and fengycin. The genome mining also identified an unknown NRPS-transAT-PKS cluster that likely produced another compound with antibiotic activity. The strain was further characterized by the assessment of abiotic stress tolerances that are required in potential probiotic agents. The selected isolate had promising results in abiotic stress tolerance; pH tolerance within the range from 4.0 to 8.0, able to survive concentrations of bile salt up to 0.4% and sodium chloride from 0 to 6.5%. In addition, the strain showed a value of hydrophobicity (31%) along with a higher value of auto-aggregation (49.9%), which demonstrates its potential ability to adhere to the intestinal wall on the basis of its cell surface traits. The strain was evaluated for susceptibility to antimicrobials and the novel B. velezensis AMB-y1 has potential to be used as a probiotic in aquaculture to control marine fish and stingray pathogens.
Assuntos
Bacillus , Probióticos , Animais , Aquicultura , Bacillus/genética , GenômicaRESUMO
Bacillus subtilis currently encompasses four subspecies, Bacillus subtilis subsp. subtilis, Bacillus subtilis subsp. inaquosorum, Bacillus subtilis subsp. spizizenii and Bacillus subtilis subsp. stercoris. Several studies based on genomic comparisons have suggested these subspecies should be promoted to species status. Previously, one of the main reasons for leaving them as subspecies was the lack of distinguishing phenotypes. In this study, we used comparative genomics to determine the genes unique to each subspecies and used these to lead us to the unique phenotypes. The results show that one difference among the subspecies is they produce different bioactive secondary metabolites. B. subtilis subsp. spizizenii is shown conserve the genes to produce mycosubtilin, bacillaene and 3,3'-neotrehalosadiamine. B. subtilis subsp. inaquosorum is shown conserve the genes to produce bacillomycin F, fengycin and an unknown PKS/NRPS cluster. B. subtilis subsp. stercoris is shown conserve the genes to produce fengycin and an unknown PKS/NRPS cluster. While B. subtilis subsp. subtilis is shown to conserve the genes to produce 3,3'-neotrehalosadiamine. In addition, we update the chemotaxonomy and phenotyping to support their promotion to species status.
Assuntos
Bacillus subtilis/classificação , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Genoma Bacteriano/genética , Lipopeptídeos/metabolismo , Lipoproteínas/metabolismo , Peptídeos Cíclicos/metabolismo , Polienos/metabolismoRESUMO
Onions can be damaged by Fusarium basal rot caused by the soilborne fungus Fusarium oxysporum f. sp. cepae (FOC). Control of this pathogen is challenging since there is limited genetic resistance in onion. The identification of molecules that inhibit this pathogen is needed. Antagonism screening showed Brevibacillus fortis NRS-1210 secreted antifungal compounds into growth medium. The spent growth medium, diluted 1:1, inhibited growth of FOC conidia after seven hours and killed 67-91% of conidia after 11 h. The spent medium also inhibited growth of propagules from F. graminearum, F. proliferatum, F. verticillioides and Galactomyces citri-aurantii. Full strength spent growth medium did not effectively kill FOC conidia and chlamydospores inoculated into a sand cornmeal mixture. In silico analysis of the B. fortis NRS-1210 genome indicated the biosynthetic clusters of several antibiotics. Fractionation of spent medium followed by reverse-phase liquid chromatography with tandem mass spectrometry analysis found that fractions with the most antifungal activity contained a combination of edeines A, B and F and no other recognized antibiotics. 1H NMR signals of the active fraction corresponded to edeine, a pentapeptide with broad spectrum antimicrobial activity which blocks translation in both prokaryotes and eukaryotes. Comparative genomics of Brevibacillus genomes shows edeine producers form a clade which consists of: Brevibacillus brevis, Brevibacillus formosus, 'Brevibacillus antibioticus', Brevibacillus schisleri, Brevibacillus fortis, and Brevibacillus porteri. This observation suggests edeine played an important role in the evolution and speciation of the Brevibacillus genus.
Assuntos
Brevibacillus/metabolismo , Edeína/biossíntese , Edeína/farmacologia , Fusarium/efeitos dos fármacos , Cebolas/microbiologia , Doenças das Plantas/prevenção & controle , Esporos Fúngicos/efeitos dos fármacos , Antifúngicos/farmacologia , Brevibacillus/classificação , Brevibacillus/genética , Edeína/química , Genoma Bacteriano/genética , Filogenia , Doenças das Plantas/microbiologia , Saccharomycetales/efeitos dos fármacos , Metabolismo Secundário/genéticaRESUMO
Bacillus cereus sensu lato strains (B. cereus group) are widely distributed in nature and have received interest for decades due to their importance in insect pest management, food production and their positive and negative repercussions in human health. Consideration of practical uses such as virulence, physiology, morphology, or ill-defined features have been applied to describe and classify species of the group. However, current comparative studies have exposed inconsistencies between evolutionary relatedness and biological significance among genomospecies of the B. cereus group. Here, the combined analyses of core-based phylogeny and all versus all Average Nucleotide Identity values based on 2116 strains were conducted to update the genomospecies circumscriptions within B. cereus group. These analyses suggested the existence of 57 genomospecies, 37 of which are novel, thus indicating that the taxonomic identities of more than 39% of the analyzed strains should be revised or updated. In addition, we found that whole-genome in silico analyses were suitable to differentiate genomospecies such as B. anthracis, B. cereus and B. thuringiensis. The prevalence of toxin and virulence factors coding genes in each of the genomospecies of the B. cereus group was also examined, using phylogeny-aware methods at wide-genome scale. Remarkably, Cry and emetic toxins, commonly assumed to be associated with B. thuringiensis and emetic B. paranthracis, respectively, did not show a positive correlation with those genomospecies. On the other hand, anthrax-like toxin and capsule-biosynthesis coding genes were positively correlated with B. anthracis genomospecies, despite not being present in all strains, and with presumably non-pathogenic genomospecies. Hence, despite these features have been so far considered relevant for industrial or medical classification of related species of the B. cereus group, they were inappropriate for their circumscription. In this study, genomospecies of the group were accurately affiliated and representative strains defined, generating a rational framework that will allow comparative analysis in epidemiological or ecological studies. Based on this classification the role of specific markers such as Type VII secretion system, cytolysin, bacillolysin, and siderophores such as petrobactin were pointed out for further analysis.
Assuntos
Bacillus anthracis , Bacillus , Bacillus cereus/genética , Humanos , Fenótipo , FilogeniaRESUMO
A putative novel clade within the genus Streptomyces was discovered following antifungal screening against Pseudogymnoascus destructans, the causative agent of white-nose syndrome, and described using multi-locus sequencing analysis. Swabs from both the cave myotis bat (Myotis velifer) and the Brazilian free-tailed bat (Tadarida brasiliensis) in southern New Mexico bore isolates AC536, AC541T and AC563, which were characterised using phylogenetic, morphological, and phenotypic analyses. Multi-locus sequence analysis positions AC541T with neighbors Streptomyces rubidus (NRRL B-24619T), Streptomyces guanduensis (NRRL B-24617T), and Streptomyces yeochonensis (NRRL B-24245T). A complete genome of the type strain was assembled to determine its taxonomy and secondary metabolite potential. ANI comparisons between all closely related types strains are shown to be well below the 95-96% species delineation. DNA-DNA relatedness between AC541T and its nearest neighbors ranged between 23.7 and 24.1% confirming novelty. Approximately 1.49 Mb or 17.76% of the whole genome is devoted to natural product biosynthesis. The DNA G + C content of the genomic DNA of the type strain is 73.13 mol %. Micromorphology depicts ovoid spores with smooth surfaces in flexuous chains. Strains presented an ivory to yellow hue on most ISP media except inorganic salts-starch agar (ISP4) and can grow on D-glucose, mannitol, and D-fructose, but exhibited little to no growth on L-arabinose, sucrose, D-xylose, inositol, L-rhamnose, D-raffinose, and cellulose. This clade possesses the capability to grow from 10 to 45 °C and 12.5% (w/v) NaCl. There was strain growth variation in pH, but all isolates thrive at alkaline levels. Based on our polyphasic study of AC541T, the strain warrants the assignment to a novel species, for which the name Streptomyces buecherae sp. nov. is proposed. The type strain is AC541T (= JCM 34263T, = ATCC TSD201T).
Assuntos
Quirópteros/microbiologia , Streptomyces/classificação , Streptomyces/isolamento & purificação , Animais , Ascomicetos , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , New Mexico , Filogenia , Análise de Sequência de DNA , Streptomyces/genéticaRESUMO
The objective of this work was to evaluate the effectiveness of the putative biocontrol agents (PBA) Bacillus paralicheniformis and Trichoderma asperelloides in vitro and in vivo to control two of the most important tomato plant diseases: vascular wilt (Fusarium oxysporum) and early blight (Alternaria alternata). The assessment of the in vitro interactions between the PBA and the phytopathogenic fungi was performed by dual confrontation assays. The biocontrol effectiveness of the individual and combined PBA treatments towards individual phytopathogen inoculations was evaluated in tomato plants. T. asperelloides was able to exert an outstanding mycoparasitic effect on both phytopathogenic fungi in the in vitro tests by hyphal strangulation and penetration. In addition, the individual PBA treatments were effective in the biocontrol of A. alternata and F. oxysporum in tomato plants reducing the plant disease severity in more than 53.8 and 66.7% for each of the pathogens, respectively. On the other hand, the combined use of the tested strains showed similar effectiveness in the biocontrol of A. alternata, but no synergism was observed. In addition, it was concluded that B. paralicheniformis protected the plants from the attack of A. alternata through the induction of the systemic resistance of the plant. This study demonstrated the effectiveness of the individual and combined use of the strains tested for the biocontrol of A. alternata and F. oxysporum in tomato plants.
Assuntos
Alternaria/patogenicidade , Bacillus/fisiologia , Agentes de Controle Biológico , Fusarium/patogenicidade , Hypocreales/fisiologia , Doenças das Plantas/microbiologia , Solanum lycopersicum/microbiologia , Interações Microbianas , Doenças das Plantas/prevenção & controleRESUMO
The current study evaluates the taxonomic positions of Lysinibacillusmangiferihumi, Lysinibacillus sphaericus, Lysinibacillustabacifolii and Lysinibacillus varians. Phylogenomic and genomic comparisons show the four strains are conspecific based on standard species thresholds for this genus (monophyletic and pairwise average nucleotide identities >96â%). Analysis of the 16S rRNA gene sequences provided in original descriptions with genome-derived 16S rRNA gene sequences from the current study showed significant differences in three of the four strains. Variant analysis of the 16S rRNA gene sequences using the genomic data showed that the 16S rRNA gene copies are polyallelic for these species. Previously reported distinguishing phenotypes were re-examined and the strains show phenotype congruence, with the exception of a few variable traits. Based on the rules of priority, L. mangiferihumi, L. tabacifolii and L. varians are later heterotypic synonyms of L. sphaericus.
Assuntos
Bacillaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genômica , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
During a screen for antifungal activity of Brevibacillus strains in the Northern Regional Research Laboratory collection we identified two strains with strong activity. Subsequent genomic sequencing and phylogenomic analysis revealed that these strains (NRRL NRS-1210T and NRRL B-41110T) are likely novel species. To confirm their taxonomic placement, we conducted a 16S rRNA phylogenetic analysis and subsequently sequenced the genomes of 10 Brevibacillus type strains with a 16S homology > 97%. Phylogenomic analysis of these type strains and of representative Brevibacillus strains deposited in GenBank also identified several novel clades that should be recognised as novel species. For one of these novel clades, we were able to obtain a publicly available isolate (ATCC 35690T) that could serve as a type strain. The three new species were subjected to a polyphasic characterisation to confirm their taxonomic status. Cells of strains NRRL NRS-1210T, NRRL B-41110T and ATCC 35690T are Gram-staining positive, motile and form tan colonies. All three strains are obligate aerobic mesophiles with a broad pH range for growth. The two most prominent fatty acids of the three strains were identified as iso-C15:0 and anteiso-C15:0. The DNA G+C contents of strains NRRL NRS-1210T, NRRL B-41110T and ATCC 35690T are 47.2 mol%, 47.1 mol% and 47.3 mol%, respectively. Based on these characteristics, three novel species are proposed: Brevibacillus fortis sp. nov. (NRRL NRS-1210T = DSM 9886T = ATCC 51666T), Brevibacillus porteri sp. nov. (NRRL B-41110T = KACC 19693T) and Brevibacillus schisleri sp. nov. (ATCC 35690T = LMG 17055T).
Assuntos
Brevibacillus/classificação , Filogenia , Composição de Bases , Brevibacillus/genética , Brevibacillus/isolamento & purificação , Brevibacillus/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Genoma Bacteriano , RNA Ribossômico 16S/genéticaRESUMO
A strain of a Gram-positive, strictly aerobic, motile, rod-shaped, endospore forming bacterium was originally isolated from rhizospheric soil of a pepper plant when screening and bioprospecting for plant beneficial microorganisms. Phylogenetic analysis of the 16S rRNA gene sequences indicated that this strain, PB300T, is closely related to Lysinibacillus macroides DMS 54T (99.6%) and Lysinibacillus xylanilyticus DSM 23493T (99.4%). In phenotypic characterisation, the novel strain was found to grow between 15 and 40 °C and tolerate up to 10% (w/v) NaCl. Furthermore, the strain was found to grow in media with pH 5 to 10 (optimal growth at pH 7.0). The predominant cellular fatty acids were observed to be iso-C15â:â0 (56.6â%), anteiso-C15â:â0 (14.6%), C16â:1ω7C alcohol (9.3%) and C16â:â0 (7.1%). The cell wall peptidoglycan contains lysine-aspartic acid, as in its close relatives. A draft genome was completed and the DNA G + C content was determined to be 37.5% (mol content). A phylogenomic analysis of the core genome of the new strain and 5 closely related type strains of the genus Lysinibacillus revealed that this strain formed a distinct monophyletic clade with the nearest neighbour being Lysinibacillus boronitolerans. DNA-DNA relatedness studies using in silico DNA-DNA hybridizations (DDH) showed relationships for the new strain were below the species threshold of 70%. Based upon the consensus of phylogenetic and phenotypic analyses, we conclude that this strain represents a novel species within the genus Lysinibacillus, for which the name Lysinibacillus capsici sp. nov. is proposed, with type strain PB300T (= NRRL B-65515T, = CCUG 72241T).
Assuntos
Bacillaceae/classificação , Bacillaceae/isolamento & purificação , Microbiologia do Solo , Bacillaceae/química , Bacillaceae/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Capsicum/crescimento & desenvolvimento , Parede Celular/química , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Hibridização de Ácido Nucleico , Peptidoglicano/análise , Filogenia , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNARESUMO
Four bacterial strains, with the capability of inhibiting Pseudogymnoascus destructans, the causative agent of white-nose syndrome, were isolated from male Townsend's big-eared bats (Corynorhinus townsendii, Family: Vespertilionidae) in New Mexico. Isolates AC161, AC162, AC208, and AC230T were characterised as a novel clade using morphological, phenotypic and phylogenetic analysis. A draft genome of the type strain was completed to determine its taxonomy and secondary metabolite biosynthetic potential. Multi-locus sequence analysis nests AC230T with neighbours Streptomyces scopuliridis (NRRL B-24574T), Streptomyces lushanensis (NRRL B-24994T), Streptomyces odonnellii (NRRL B-24891T) and Streptomyces niveus (NRRL 2466T). Further phylogenetic analysis showed the MLSA distances between AC230T and its near neighbours are much greater than the generally accepted threshold (> 0.007) for bacterial species delineation. DNA-DNA relatedness between AC230T and its near neighbours ranged between 25.7 ± 2.1 and 29.9 ± 2.4%. The DNA G+C content of the genomic DNA of the type strain is 71.7 mol%. Isolate AC230T presents a white to ivory hue on most ISP media and its micromorphology exhibits ovoid spores with smooth surfaces in flexuous chains. Based on our study of AC230T, the strain warrants the assignment to a novel species, for which the name Streptomyces corynorhini sp. nov. is proposed. The type strain is AC230T (= JCM 33171T, = ATCC TSD155T).
Assuntos
Quirópteros/microbiologia , Streptomyces/classificação , Streptomyces/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Redes e Vias Metabólicas/genética , Microscopia Eletrônica de Varredura , Tipagem de Sequências Multilocus , New Mexico , Hibridização de Ácido Nucleico , Filogenia , Esporos Bacterianos/ultraestrutura , Streptomyces/genética , Streptomyces/fisiologia , Sequenciamento Completo do GenomaRESUMO
Acinetobacter lactucae and Acinetobacter dijkshoorniae were recently described as novel species, and both were reported to be closely related to Acinetobacter pittii. Because they were reviewed and published almost concurrently, their descriptions did not include a specific comparison between these two novel species. Genomic data were provided in both initial descriptions, which simplifies the comparisons. Genome comparisons based on in silico DNA-DNA hybridizations, average nucleotide identity and core genome phylogeny of the type strain genomes establish that these strains are conspecific. Based on the rules of priority, A. dijkshoorniae should be reclassified as a later heterotypic synonym of A. lactucae.
Assuntos
Acinetobacter/classificação , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Hibridização de Ácido Nucleico , Análise de Sequência de DNARESUMO
A novel heterotrophic, Gram-stain-negative, aerobic, rod-shaped, pale yellow, non-motile and non-spore-forming bacterium, designated strain F2T, was isolated from marine sediment collected from the Weihai coast, Shandong Province, PR China. Optimal growth occurred at 33 °C (range, 10-37 °C), with 3.0-4.0â% (w/v) NaCl (1.0-8.0â%) and at pH 7.5-8.0 (pH 6.5-9.0). Q-8 was the sole respiratory quinone. The major polar lipids of strain F2T were phosphatidylmonomethylethanolamine, phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and two unidentified polar lipids. The major cellular fatty acid in strain F2T was iso-C15â:â0. The genomic DNA G+C content of the strain was 48.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that strain F2T is most closely related to Marinicella litoralis JCM 16154T (97.5â%) and Marinicella pacifica sw153T (96.0â%). Based on the results of our polyphasic analysis, we conclude that strain F2T represents a novel species of the genus Marinicella, for which the name Marinicella sediminis sp. nov. is proposed. The type strain of the new species is F2T (=KCTC 42953T=MCCC 1H00149T).
Assuntos
Alcanivoraceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alcanivoraceae/genética , Alcanivoraceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
We report the development of a publicly accessible, curated nucleotide sequence database of hypocrealean entomopathogenic fungi. The goal is to provide a platform for users to easily access sequence data from taxonomic reference strains. The database can be used to accurately identify unknown entomopathogenic fungi based on sequence data for a variety of phylogenetically informative loci. The database provides full multi-locus sequence alignment capabilities. The initial release contains data compiled for 525 strains covering the phylogenetic diversity of three important entomopathogenic families: Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae. Furthermore, Entomopathogen ID can be expanded to other fungal clades of insect pathogens, as sequence data becomes available. The database will allow isolate characterisation and evolutionary analyses. We contend that this freely available, web-accessible database will facilitate the broader community to accurately identify fungal entomopathogens, which will allow users to communicate research results more effectively.
Assuntos
Hypocreales/genética , Insetos/microbiologia , Animais , DNA Fúngico/genética , Hypocreales/classificação , FilogeniaRESUMO
At least two-thirds of commercial antibiotics today are derived from Actinobacteria, more specifically from the genus Streptomyces Antibiotic resistance and new emerging diseases pose great challenges in the field of microbiology. Cave systems, in which actinobacteria are ubiquitous and abundant, represent new opportunities for the discovery of novel bacterial species and the study of their interactions with emergent pathogens. White-nose syndrome is an invasive bat disease caused by the fungus Pseudogymnoascus destructans, which has killed more than six million bats in the last 7 years. In this study, we isolated naturally occurring actinobacteria from white-nose syndrome (WNS)-free bats from five cave systems and surface locations in the vicinity in New Mexico and Arizona, USA. We sequenced the 16S rRNA region and tested 632 isolates from 12 different bat species using a bilayer plate method to evaluate antifungal activity. Thirty-six actinobacteria inhibited or stopped the growth of P. destructans, with 32 (88.9%) actinobacteria belonging to the genus Streptomyces Isolates in the genera Rhodococcus, Streptosporangium, Luteipulveratus, and Nocardiopsis also showed inhibition. Twenty-five of the isolates with antifungal activity against P. destructans represent 15 novel Streptomyces spp. based on multilocus sequence analysis. Our results suggest that bats in western North America caves possess novel bacterial microbiota with the potential to inhibit P. destructansIMPORTANCE This study reports the largest collection of actinobacteria from bats with activity against Pseudogymnoascus destructans, the fungal causative agent of white-nose syndrome. Using multigene analysis, we discovered 15 potential novel species. This research demonstrates that bats and caves may serve as a rich reservoir for novel Streptomyces species with antimicrobial bioactive compounds.
Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Quirópteros/microbiologia , Streptomyces/metabolismo , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Doenças dos Animais/microbiologia , Animais , Arizona , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , DNA Bacteriano , Genes Bacterianos , Testes de Sensibilidade Microbiana , Microbiota , Tipagem de Sequências Multilocus , Micoses/microbiologia , Micoses/prevenção & controle , Micoses/veterinária , América do Norte , Nariz/microbiologia , Filogenia , RNA Ribossômico 16S , Streptomyces/classificação , Streptomyces/genética , Streptomyces/isolamento & purificaçãoRESUMO
A Gram-stain-negative and facultatively anaerobic bacterium, designated WDS2C40T, was isolated from a marine solar saltern in Weihai, China. Cells of strain WDS2C40T were 0.4-0.5 µm wide and 4.0-9.0 µm long, catalase-positive and oxidase-negative. Strain WDS2C40T was tolerant to moderate salt concentrations. Growth occurred at 20-42 °C (optimum, 37-40 °C), at pH 7.0-8.5 (optimum, 7.5-8.0) and with 2-16â% (w/v) NaCl (optimum, 6-8â%). A phylogenetic analysis of the 16S rRNA gene indicated that strain WDS2C40T was a member of the genus Gracilimonas within the family Balneolaceae. The most closely related neighbour was Gracilimonas rosea JCM 18898T (95.92â% similarity). The major respiratory quinone of strain WDS2C40T was menaquinone MK-7, and the dominant fatty acids were iso-C13â:â0, iso-C15â:â0 and summed feature 3. The major polar lipids were diphosphatidylglycerol, one kind of glycolipid and two unidentified phospholipids. The genomic DNA G+C content was 41.7 mol%. Based on this polyphasic taxonomic study, strain WDS2C40T is considered to represent a novel species in the genus Gracilimonas, for which the name Gracilimonas halophila sp. nov. is proposed. The type strain is WDS2C40T (=KCTC 52042T=MCCC 1H00135T).