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Despite the well documented link between cover cropping and soil microbiology, the influence of specific cover crop species on soil microbes remains poorly understood. We evaluated how soil fungal communities in a no till system respond to four cover crop treatments: no cover crop (REF), cereal ryegrass (CRYE), wild pennycress (WPEN), and a mix of pea, clover, radish, and oat (PCRO). Soil samples were collected from experimental plots following termination of cover crops from depths of 0-2 cm and 2-4 cm where cover crops had significantly increased soil organic matter. There was no significant interaction between soil depth and cover crop treatment on either alpha diversity or beta diversity. All cover crop treatments (CRYE, PCRO, and WPEN) enhanced soil fungal richness but only CRYE enhanced soil fungal diversity and altered the fungal community structure. Soil depth altered the fungal community structure but had no effect on fungal diversity and richness. Genus Fusarium which includes some of the most economically destructive pathogens was more abundant in REF and PCRO treatments compared to CRYE and WPEN. In contrast, genus Mortierella which is known to promote plant health was more abundant in all cover crop treatments relative to the REF. These findings demonstrate that cover cropping can increase soil fungal species richness and alter fungal community structure, potentially promoting the abundance of beneficial fungi and reducing the abundance of some plant pathogens within the genus Fusarium. These effects are dependent on cover crop species, a factor that should be considered when selecting appropriate cover crops for a particular cropping system., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

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-350 T (99.7%) and Lysinibacillus sphaericus NRRL B-23268 T (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-C 15: 0 (52.3%), anteiso-C 15: 0 (14.8%), C 16:1 ω7C alcohol (11.2%), and C 16: 0 (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 PB211 T (= NRRL B-65672 T , = CCUG 77181 T )., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Introduction: A diagnosis of oral squamous cell carcinoma in adolescent patients is extremely rare. When an oral squamous cell carcinoma lesion arises near the teeth and/or periodontium, it can be easily misdiagnosed as an inflammatory condition of endodontic or periodontal origin., Methods: This is a case report of an otherwise healthy 14-year-old patient who was referred for endodontic evaluation and treatment of a soft-tissue swelling in the anterior maxilla., Results: The unexpected definitive diagnosis of invasive oral squamous cell carcinoma underscores the importance of proper diagnostic testing., Conclusions: Accurate interpretation of pulp testing results, periapical and cone beam computed tomography imaging, timely biopsy, and prompt definitive treatment are critical when a lesion of nonodontogenic origin is suspected., (Copyright © 2024 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

This study evaluated the accuracy of the Wirele-X (Forum Tec, Ashkelon, Israel), a novel Bluetooth-enabled wireless electronic apex locator. Thirty-one extracted teeth with mature apices were used. Under 10X magnification, the actual canal lengths were determined. The teeth were embedded in alginate and electronic canal lengths were obtained using the Root ZX II and Wirele-X electronic apex locators. The actual canal lengths and electronic canal lengths were compared with Student's t-test. The average distance from the file tip to the actual canal length was -0.11 mm (±0.16) for the Root ZX II, and - 0.07 mm (±0.21) for the Wirele-X. There were no statistically significant differences between the two electronic apex locators in their ability to determine the actual canal length (p > 0.05). The wireless apex locator (Wirele-X) and the wired apex locator (Root ZX II) were found to be equally accurate., (© 2022 The Authors. Australian Endodontic Journal published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Endodontology Inc.)

The aims of this study were to determine the efficacy of the KontrolFlex™ Accufile™ compared to the READY•STEEL™ Flexofile® using an electronic apex locator and to evaluate the instrument's design via scanning electron microscopy. Actual canal lengths of 30 extracted teeth were determined under magnification. An alginate model was used to determine experimental canal lengths with the Root ZX II apex locator (EAL) and size #10 Accufiles and Flexofiles. Differences between actual lengths and experimental lengths were compared with Student's t test. The average experimental lengths were short of the actual length by -0.10 mm (±0.34) and -0.12 mm (±0.16) for the Accufile and Flexofile, respectively with no statistical difference (p > 0.05). SEM images revealed similar non-cutting Batt tips and a square cross-section for the Accufile and triangular for the Flexofile. Both files provided similarly high levels of reliability when used with the Root ZX II EAL., (© 2022 The Authors. Australian Endodontic Journal published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Endodontology Inc.)

The compound 2,4-diacetylphloroglucinol (DAPG) is a broad-spectrum antibiotic that is primarily produced by Pseudomonas spp. DAPG plays an important role in the biocontrol disease suppressing activity of Pseudomonas spp. In the current study, we report the discovery of the DAPG biosynthetic cluster in strains of Chromobacterium vaccinii isolated from Brazilian aquatic environments and the distribution of the biosynthetic cluster in the Chromobacterium genus. Phylogenetic analysis of the phlD protein suggests the biosynthetic cluster probably entered the genus of Chromobacterium after a horizontal gene transfer event with a member of the Pseudomonas fluorescens group. We were able to detect trace amounts of DAPG in wild type cultures and confirm the function of the cluster with heterologous expression in Escherichia coli. In addition, we identified and verified the presence of other secondary metabolites in these strains. We also confirmed the ability of C. vaccinii strains to produce bioactive pigment violacein and bioactive cyclic depsipeptide FR900359. Both compounds have been reported to have antimicrobial and insecticidal activities. These compounds suggest strains of C. vaccinii should be further explored for their potential as biocontrol agents., (© 2023. Springer Nature Limited.)

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 10 8  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., (© 2023. The Author(s).)

Salinity stress has significant deleterious effects on agricultural lands and plant yields. Plants undergo a series of physiological and molecular changes to reduce salt-induced damage. However, these mechanisms remain insufficient. The inoculation of plant growth promoting bacteria to improve plant health under stress conditions offers promise. Bacillus velezensis FMH2 has been shown to protect tomato fruits against black mold disease and to improve seed tolerance to abiotic stresses. During this study, the major physiological and metabolic changes connected with FMH2 mitigation of abiotic stress tolerance in tomato plants were explored. In presence of different salt levels, FMH2 showed a high potentiality to colonize internal plant tissues and to produce several plant growth promoting metabolites such as siderophores, indole acetic acid, and hydrolytic enzymes. FMH2-treatment promoted plant growth (root structure, plant elongation, leaf emission, fresh and dry weights, water content, etc.) in absence as well as in presence of salt stress. FMH2 treatment decreased endogenous Na + accumulation and increased K + and Ca 2+ uptake. Furthermore, B. velezensis FMH2-treatment improved chlorophyll contents, membrane integrity and phenol peroxidase concentrations, and reduced malondialdehyde and hydrogen peroxide levels under saline conditions with a significant salinity × strain interaction. The present study suggests the endophytic strain FMH2 involved different mechanisms and regulatory functions to enhance plant oxidative systems and regulate ion uptake mechanisms supporting both growth and stress management., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

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 (H 2 O 2 ) levels under saline conditions with a significant salinity × strain interaction. Furthermore, FMH45 inoculation significantly decreased endogenous Na + accumulation, increased K + and Ca 2+ uptake, and thereby improved K + /Na + and Ca 2+ /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.

Microsporidia are naturally occurring fungal-related parasites that can infect nearly all animal hosts, but their biocontrol potential of insect pests is routinely overlooked in agriculture and forestry. This research brings the first report describing the natural occurrence of a microsporidium causing disease in field-collected populations of the invasive eucalyptus snout beetle, Gonipterus platensis (Coleoptera: Curculionidae), a major destructive pest of eucalyptus plantations in Brazil. Adult beetles were collected during field surveys in commercial eucalyptus plantations in southern Brazil to be examined and dissected with typical symptoms to verify presence of microsporidian spores in haemolymph. From 14 plantations in different sites, the natural infection occurrence in these populations ranged from 0 to 65%, while a lab colony exhibited an infection incidence of 70%. Spore density in haemolymph of symptomatic insects averaged 2.1 (± 0.4) × 10 7 spores/beetle. Symptoms in infected adults were identified by an abnormal abdomen with malformation of the second pair of wings, impairing their flight activity. Electron transmission microscopy of the pathogen showed morphological features similar to species belonging to the genus Nosema or Vairimorpha. Phylogenetic analysis of the full-length small subunit ribosomal RNA gene suggests this pathogen's placement in the genus Vairimorpha, but with a sequence identity of ~ 94% with the nearest neighbours. The low level of sequence identity suggests this pathogen may represent a novel taxon in the genus and further requires whole genome sequencing for definitive taxonomic resolution. These findings provide insights on the natural occurrence of this novel pathogen of this invasive pest in Eucalyptus plantations in Brazil. Further studies are needed to determine potential of this microsporidium in the design of conservative or augmentative biological control programs for this invasive pest.

Culturing the entomopathogenic fungus, Beauveria bassiana , under high glucose concentrations coupled with high aeration results in a fungal developmental shift from hyphal growth to mostly blastospores (yeast-like cells). The underlying molecular mechanisms involved in this shift remain elusive. A systematic transcriptome analysis of the differential gene expression was preformed to uncover the fungal transcriptomic response to osmotic and oxidative stresses associated with the resulting high blastospore yield. Differential gene expression was compared under moderate (10% w/v) and high (20% w/v) glucose concentrations daily for three days. The RNAseq-based transcriptomic results depicted a higher proportion of downregulated genes when the fungus was grown under 20% glucose than 10%. Additional experiments explored a broader glucose range (4, 8, 12, 16, 20% w/v) with phenotype assessment and qRT-PCR transcript abundance measurements of selected genes. Antioxidant, calcium transport, conidiation, and osmosensor-related genes were highly upregulated in higher glucose titers (16-20%) compared to growth in lower glucose (4-6%) concentrations. The class 1 hydrophobin gene ( Hyd1 ) was highly expressed throughout the culturing. Hyd1 is known to be involved in spore coat rodlet layer assembly, and indicates that blastospores or another cell type containing hydrophobin 1 is expressed in the haemocoel during the infection process. Furthermore, we found implications of the HOG signaling pathway with upregulation of homologous genes Ssk2 and Hog1 for all fermentation time points under hyperosmotic medium (20% glucose). These findings expand our knowledge of the molecular mechanisms behind blastospore development and may help facilitate large-scale industrial production of B. bassiana blastospores for pest control applications., Competing Interests: Author GMM was employed by Brazilian Agricultural Research Corporation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Mascarin, Iwanicki, Ramirez, Delalibera and Dunlap.)

We isolated a filamentous, thermophilic, and first anaerobic representative of the genus Thermoactinomyces, designated strain AMNI-1 T , from a biogas plant in Tyrol, Austria and report the results of a phenotypic, genetic, and phylogenetic investigation. Strain AMNI-1 T 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-1 T 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-1 T (= DSM 110094 T  = LMG 31503 T ). The description of the genus Thermoactinomyces is emended accordingly.

A Gram-stain positive, aerobic, motile, rod-shaped bacterium designated as strain CBP-2801 T 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-2801 T 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-2801 T represents a novel species, for which the name Cohnella zeiphila sp. nov. is proposed. The type strain is CBP-2801 T (= DSM 111598 = ATCC TSD-230).

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.

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.

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, AC541 T and AC563, which were characterised using phylogenetic, morphological, and phenotypic analyses. Multi-locus sequence analysis positions AC541 T with neighbors Streptomyces rubidus (NRRL B-24619 T ), Streptomyces guanduensis (NRRL B-24617 T ), and Streptomyces yeochonensis (NRRL B-24245 T ). 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 AC541 T 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 AC541 T , the strain warrants the assignment to a novel species, for which the name Streptomyces buecherae sp. nov. is proposed. The type strain is AC541 T (= JCM 34263 T , = ATCC TSD201 T ).

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.

The assembly of single-amplified genomes (SAGs) and metagenome-assembled genomes (MAGs) has led to a surge in genome-based discoveries of members affiliated with Archaea and Bacteria, bringing with it a need to develop guidelines for nomenclature of uncultivated microorganisms. The International Code of Nomenclature of Prokaryotes (ICNP) only recognizes cultures as 'type material', thereby preventing the naming of uncultivated organisms. In this Consensus Statement, we propose two potential paths to solve this nomenclatural conundrum. One option is the adoption of previously proposed modifications to the ICNP to recognize DNA sequences as acceptable type material; the other option creates a nomenclatural code for uncultivated Archaea and Bacteria that could eventually be merged with the ICNP in the future. Regardless of the path taken, we believe that action is needed now within the scientific community to develop consistent rules for nomenclature of uncultivated taxa in order to provide clarity and stability, and to effectively communicate microbial diversity.

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. 1 H 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.

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.

Six fungal isolates of Beauveria bassiana (Balsamo) Vuillemin and one isolate of Metarhizium anisopliae (Metschnikoff) Sorokin were isolated and evaluated for their pathogenicity to Icerya seychellarum (Westwood) and Aulacaspis tubercularis Newstead. There is a positive correlation between the concentration of the fungal blastospore concentrations and the percentage of mortality. Bio-efficacy increased significantly after inoculation with increasing concentration of blastospores and elapsed time up to 12 d after inoculation. The mortality of nymphs exposed to fungal isolates at various concentrations varied between 2.5 and 88.8%. Probit analysis of data at 95% confidence limits of LC50 and LT50s showed significant differences in the susceptibility of nymphs of I. seychellarum and A. tubercularis to the tested fungal isolates. The fungal isolates of Egy-6 and Egy-9 were the most effective against I. seychellarum and A. tubercularis, respectively. They had the lowest LC50 (4.20 × 105 and 5.71 × 103 blastospore ml-1) and LT50 (ranged from 4.61 to 9.79 and 4.84 to 8.71 d), respectively. The current study showed that all the fungal isolates yielded moderate mortality rates of nymphs and adult female populations of both the tested insect pests. To our knowledge, this is the first report of bio-efficacy of Beauveria and Metarhizium isolates against members of the Diaspidadae and Monophlebidae family insects. These results establish that the use of these native entomopathogenic fungi isolates of B. bassiana (Egy-3, Egy-4, Egy-6, Egy-7, Egy-9, and Egy-10) and M. anisopliae (Egy-5) could be considered for further development as microbial control agents of the mealybug and scale insects as a potential biological agent for use in an IPM program., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The uses of halotolerant bacteria isolated from naturally saline habitats have the potential to be useful crop protection agents for plants in stressful conditions. These beneficial microbes generate several plant growth regulators and bioactive molecules, which enhance plant protection from adversities, such as plant pathogens, salts and metals stresses. In this study, 15 halotolerant bacterial strains endowed with important antimicrobial activities were isolated from Sfax solar saltern (Tunisia). All of these strains were characterized by biochemical and molecular tools aiming to investigate their in-vitro and in-vivo antifungal potentialities, plant growth promotion capabilities and metal tolerance abilities under saline stress condition. The 16S rRNA gene sequencing showed that the isolated strains were affiliated to different phylum and three species were described for the first time as plant growth promoting strains (Idiomarina zobelli FMH6v, Nesterenkonia halotolerans FMH10 and Halomonas janggokensis FMH54). The tested strains exhibited several potentialities: to tolerate high salt and heavy metal concentrations, to produce biosurfactants, exopolysaccharides and extracellular hydrolytic enzymes, to form biofilms and to liberate plant promoting substances. Eight strains were able to protect tomatoes fruits from the proliferation of the fungal disease caused by Botrytis cinerea and six strains improved plant vigor indexes. Principal component analysis showed an important correlation between in-vitro and in-vivo potentialities and two strains Bacillus velezensis FMH2 and Bacillus subtilis subsp. spizizenii FMH45 were statistically considered as the most effective strains in protecting plants from fungal pathogens attack and promoting the growth of tomatoes seedlings under saline and multi heavy-metals stress conditions., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

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 >96 %). 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.

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 AC230 T 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 AC230 T with neighbours Streptomyces scopuliridis (NRRL B-24574 T ), Streptomyces lushanensis (NRRL B-24994 T ), Streptomyces odonnellii (NRRL B-24891 T ) and Streptomyces niveus (NRRL 2466 T ). Further phylogenetic analysis showed the MLSA distances between AC230 T and its near neighbours are much greater than the generally accepted threshold (> 0.007) for bacterial species delineation. DNA-DNA relatedness between AC230 T 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 AC230 T 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 AC230 T , the strain warrants the assignment to a novel species, for which the name Streptomyces corynorhini sp. nov. is proposed. The type strain is AC230 T (= JCM 33171 T , = ATCC TSD155 T ).

Iturins and closely related lipopeptides constitute a family of antifungal compounds known as iturinic lipopeptides that are produced by species in the Bacillus subtilis group. The compounds that comprise the family are: iturin, bacillomycin D, bacillomycin F, bacillomycin L, mycosubtilin, and mojavensin. These lipopeptides are prominent in many Bacillus strains that have been commercialized as biological control agents against fungal plant pathogens and as plant growth promoters. The compounds are cyclic heptapeptides with a variable length alkyl sidechain, which confers surface activity properties resulting in an affinity for fungal membranes. Above a certain concentration, enough molecules enter the fungal cell membrane to create a pore in the cell wall, which leads to loss of cell contents and cell death. This study identified 330 iturinic lipopeptide clusters in publicly available genomes from the B. subtilis species group. The clusters were subsequently assigned into distinguishable types on the basis of their unique amino acid sequences and then verified by HPLC MS/MS analysis. The results show some lipopeptides are only produced by one species, whereas certain others can produce up to three. In addition, four species previously not known to produce iturinic lipopeptides were identified. The distribution of these compounds among the B. subtilis group species suggests that they play an important role in their speciation and evolution.

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, PB300 T , is closely related to Lysinibacillus macroides DMS 54 T (99.6%) and Lysinibacillus xylanilyticus DSM 23493 T (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-C 15 : 0 (56.6 %), anteiso-C 15 : 0 (14.6%), C 16 :1 ω7C alcohol (9.3%) and C 16 : 0 (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 PB300 T (= NRRL B-65515 T , = CCUG 72241 T ).

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-1210 T and NRRL B-41110 T ) 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 35690 T ) 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-1210 T , NRRL B-41110 T and ATCC 35690 T 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-1210 T , NRRL B-41110 T and ATCC 35690 T 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-1210 T  = DSM 9886 T  = ATCC 51666 T ), Brevibacillus porteri sp. nov. (NRRL B-41110 T  = KACC 19693 T ) and Brevibacillus schisleri sp. nov. (ATCC 35690 T  = LMG 17055 T ).

A strain of bacteria in the Bacillus subtilis species complex was isolated from a building's air vent in the Washington DC area, USA, and produced strong antifungal activity with in vitro assays. This strain, designated (HU Biol-II), showed pronounced inhibitory effects on mycelial growth of a wide spectrum of fungi. The objectives of this study were to use genome sequencing to confirm the taxonomy of HU Biol-II, evaluate its antifungal activity and implement genome mining and HPLC-MS/MS to characterize the bioactive secondary metabolites. The strain, as determined by multilocus sequence alignment analysis, was identified as a member of Bacillus subtilis subsp. inaquosorum clade. Core genome phylogeny showed that the isolate is most closely related to B. subtilis subsp. inaquosorum strain DE111, a commercially produced human probiotic. The investigation identified eight bioactive metabolite clusters in the genome. HPLC MS/MS was able to confirm the production of seven of the metabolites. This study is the first to report the production of two antifungal cyclic lipopeptides (bacillomycin F and fengycin) from a member of B. subtilis subsp. inaquosorum. The strain also produced the antibacterial aurantinin B, which confirms the biosynthetic cluster responsible for its production. Comparative genomics and metabolomics demonstrated the commercial probiotic strain DE111 produced the same metabolites, with the exception of aurantinin B. These findings are the first description of the secondary metabolites produced by a strain of B. subtilis subsp. inaquosorum., (Published by Elsevier GmbH.)

Selecting entomopathogenic fungal isolates with resilience to environmental stresses, optimal mass production characteristics, and with high virulence to target pests favors the development of mycopesticides. A case in point, Cordyceps (= Isaria) javanica has been extensively investigated for non-chemical control of whiteflies worldwide. We phylogenetically characterized 11 native C. javanica isolates from Northeastern and Central Brazil. These isolates were screened for tolerance to heat-shock, UV-B radiation, osmotic and oxidative stresses, as well as conidial production on cereal grain and insecticidal activity against the whitefly Bemisia tabaci (MEAM 1) in the laboratory. All isolates were pathogenic to whiteflies and significant (3-fold) differences in median lethal concentration were observed among isolates. Furthermore, pronounced differences among isolates were found for stress factors and conidial production. Using principal component analysis, our results highlighted three major clusters formed by isolates (i) resistant to osmotic and oxidative stress, (ii) resilient to UV-B, and (iii) with high virulence, conidial production and heat tolerance. Overall, isolate CG1228 performed best based on multi-stress resistance, mass production and virulence attributes in the laboratory. This study highlights the importance of exploring natural variation in entomopathogenic fungi for selection of appropriate isolates for effective biocontrol of insect pests coupled with mass production characteristics and abiotic stress tolerances., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Autodissemination and foliar sprays of PFR-97 (Certis Inc., Columbia, MD) microbial insecticide, a blastospore formulation of Isaria fumosorosea Wize (Hypocreales: Cordycipitaceae), were evaluated for control of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), on residential citrus. Seasonal trials on dooryard trees in South Texas evaluated: 1) pathogenicity of I. fumosorosea (Ifr) spores on autodisseminators (dispensers) deployed up to 3 wk on grapefruit trees; 2) psyllid control on several citrus species by dispensers and sprays; 3) infection range of the dispenser. Decline in spore pathogenicity over time was similar among dispensers during fall, winter, or spring and decreased by 30% after 1 d, 59% after 7 d, 81% after 14 d, and 100% after 21 d. Dispensers or sprays were equally effective for psyllid control on heavily infested lime trees from fall to spring and reduced mean reproduction (cumulative eggs) by 90% and mean attack intensity (cumulative psyllid-days) of adults by 76% and nymphs by 82%. Dispensers or sprays were also equally effective for psyllid control on lightly infested lime trees from spring to mid-summer and on orange or grapefruit trees from fall to winter. Very light infestations on grapefruit trees from spring to mid-summer were not significantly reduced by dispensers or sprays. Psyllid control was not improved by combining dispensers and sprays. Adult psyllids infected by Ifr were recovered in trees located 3-4 m away from trees with dispensers but not at greater distances. PFR-97 dispensers could be a treatment option for D. citri in settings where chemical control is problematic.

A novel heterotrophic, Gram-stain-negative, aerobic, rod-shaped, pale yellow, non-motile and non-spore-forming bacterium, designated strain F2 T , 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 3.0-4.0 % (w/v) NaCl (1.0-8.0 %) 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 F2 T were phosphatidylmonomethylethanolamine, phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and two unidentified polar lipids. The major cellular fatty acid in strain F2 T was iso-C15 : 0. The genomic DNA G+C content of the strain was 48.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that strain F2 T is most closely related to Marinicella litoralis JCM 16154 T (97.5 %) and Marinicella pacifica sw153 T (96.0 %). Based on the results of our polyphasic analysis, we conclude that strain F2 T 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 F2 T (=KCTC 42953 T =MCCC 1H00149 T ).

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.

Agriculture accounts for ~ 70% of all water use and the world population is increasing annually; soon more people will need to be fed, while also using less water. The use of plant-associated bacteria (PAB) is an eco-friendly alternative that can increase crop water use efficiency. This work aimed to study the effect of some PAB on increasing soybean tolerance to drought stress, the mechanisms of the drought tolerance process, and the effect of the PAB on promoting plant growth and on the biocontrol of Sclerotinia sclerotiorum. PAB were isolated from soybean rhizosphere and S. sclerotiorum sclerotia. The strains identified as UFGS1 (Bacillus subtilis), UFGS2 (Bacillus thuringiensis), UFGRB2 and UFGRB3 (Bacillus cereus) were selected on their ability to grow in media with reduced water activity. Soybean plants were inoculated with the PAB and evaluated for growth promotion, physiological and molecular parameters, after drought stress. Under drought stress, UFGS2 and UFGRB2 sustained potential quantum efficiency of PSII (Fv/Fm), while a decrease was found in the control plants. Moreover, UFGS2 and UFGRB3 maintained the photosynthetic rates in non-stressed conditions compared to the control. UFGS2-treated plants showed a higher stomatal conductance and higher transpiration than the control, after drought stress. Some PAB-treated plants also had other beneficial phenotypes, such as increases in fresh and dried biomass relative to the control. Differential gene expression analysis of genes involved in plant stress pathways shows changes in expression in PAB-treated plants. Results from this study suggest that PAB can mitigate drought stress in soybean and may improve water efficiency under certain conditions.

Alternative methods of mosquito control are needed to tackle the rising burden of mosquito-borne diseases while minimizing the use of synthetic insecticides, which are threatened by the rapid increase in insecticide resistance in mosquito populations. Fungal biopesticides show great promise as potential alternatives because of their ecofriendly nature and ability to infect mosquitoes on contact. Here we describe the temporospatial interactions between the mosquito Aedes aegypti and several entomopathogenic fungi. Fungal infection assays followed by the molecular assessment of infection-responsive genes revealed an intricate interaction between the mosquito immune system and entomopathogenic fungi. We observed contrasting tissue and time-specific differences in the activation of immune signaling pathways and antimicrobial peptide expression. In addition, these antifungal responses appear to vary according to the fungal entomopathogen used in the infection. Enzyme activity-based assays coupled with gene expression analysis of prophenoloxidase genes revealed a reduction in phenoloxidase (PO) activity in mosquitoes infected with the most virulent fungal strains at 3 and 6d post-fungal infection. Moreover, fungal infection led to an increase in midgut microbiota that appear to be attributed in part to reduced midgut reactive oxygen species (ROS) activity. This indicates that the fungal infection has far reaching effects on other microbes naturally associated with mosquitoes. This study also revealed that despite fungal recognition and immune elicitation by the mosquito, it is unable to successfully eliminate the entomopathogenic fungal infection. Our study provides new insights into this intricate multipartite interaction and contributes to a better understanding of mosquito antifungal immunity.

The fungus Fusarium verticillioides is a maize pathogen that can produce fumonisin mycotoxins in ears under certain environmental conditions. Because fumonisins pose health risks to humans and livestock, control strategies with minimal risk to the environment are needed to reduce fumonisin contamination. Host-induced gene silencing is a promising technique in which double-stranded RNA expressed in the plant host is absorbed by an invading fungus and down-regulates genes critical for pathogenicity or mycotoxin production in the fungus. A key preliminary step of this technique is identification of DNA segments within the targeted fungal gene that can effectively silence the gene. Here, we used segments of the fumonisin biosynthetic gene FUM1 to generate double-stranded RNA in F. verticillioides. Several of the resulting transformants exhibited reduced FUM1 gene expression and fumonisin production (24- to 3675-fold reduction in fumonisin FB 1 ). Similar reductions in fumonisin production resulted from double-stranded RNA constructs with segments of FUM8, another fumonisin biosynthetic gene (3.5- to 2240-fold reduction in fumonisin FB 1 ). FUM1 or FUM8 silencing constructs were transformed into three isolates of F. verticillioides. Whole genome sequence analysis of seven transformants revealed that reductions in fumonisin production were not due to mutation of the fumonisin biosynthetic gene cluster and revealed a complex pattern of plasmid integration. These results suggest the cloned FUM1 or FUM8 gene segments could be expressed in maize for host-induced gene silencing of fumonisin production.

Aims: Nitrogen is a critical element in industrial fermentation media. This study investigated the influence of various nitrogen sources on blastospore production, desiccation tolerance and storage stability using two strains of the cosmopolitan insect-pathogenic fungus Beauveria bassiana., Methods and Results: Complex organic sources of nitrogen such as soy flour, autolysed yeast and cottonseed flour induced great numbers of blastospores after 2-3 days of fermentation, which also survived drying and remained viable (32-56% survival) after 9 months storage at 4°C, although variations were found between strains. Nitrogen availability in the form of free amino acids directly influenced blastospore production and resistance to desiccation. Increasing glucose and nitrogen concentrations up to 120 and 30 g l -1 , respectively, did not improve blastospore production but enhanced desiccation tolerance. Cell viability after drying and upon fast-rehydration was increased when ≥25 g acid-hydrolysed casein per litre was supplemented in the liquid culture medium., Conclusions: These findings indicate that low-cost complex nitrogen compounds are suitable to enhance yeast-like growth by B. bassiana with good desiccation tolerance and therefore support its further scale-up production as a mycoinsecticide., Significance and Impact of the Study: Nitrogen is the most expensive nutrient in liquid media composition, but this study underscores the feasibility of using low-cost nitrogen compounds composed mainly of agro-industrial by-products for rapid production of desiccation-tolerant B. bassiana blastospores by liquid culture fermentation., (© 2018 The Society for Applied Microbiology.)

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.

The current study evaluates the potential of using high resolution DNA melting assays to discriminate species in the genus Isaria. The study utilizes a previously identified 103 base pair PCR amplicon, which was reported to be selective for Isaria fumosorosea. Our study finds the amplicon selective for Isaria javanica and Isaria poprawskii when assayed against all members of the genus. In addition, the high resolution melting profile of this amplicon can be used to discriminate between I. javanica, I. poprawskii and a 1:1 mixture of the two species. The practical application of this technique was confirmed using a bioassay on whitefly nymphs (Bemisia tabaci biotype B) inoculated with I. javanica, I. poprawskii or a 1:1 mixture of the two species. This assay provides a simple assay to identify these two species of entomopathogenic fungi., (Published by Elsevier Inc.)

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 2-16 % (w/v) NaCl (optimum, 6-8 %). 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 (95.92 % similarity). The major respiratory quinone of strain WDS2C40T was menaquinone MK-7, and the dominant fatty acids were iso-C13 : 0, iso-C15 : 0 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).

A Gram-stain-positive, aerobic, motile, endospore-forming bacterium, designated strain J15A17T, was isolated from sediment of the South China Sea. The strain was oxidase-positive and catalase-negative. Optimal growth occurred at 33 °C, pH 7.5 and in the presence of 3 % (w/v) NaCl. On the basis of 16S rRNA gene sequence analysis, the strain showed closest similarity (92.8 %) to Paenibacillus puldeungensis strain CAU 9324T. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate forms a separate branch within the family Paenibacillaceae, with the genus Cohnella as the most closely related genus. The DNA G+C content of strain J15A17T was 37.4 mol%. The strain contained MK-7 as the sole respiratory quinone; anteiso-C15 : 0 and iso-C16 : 0 were the major cellular fatty acids; and its polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid and four unidentified phospholipids. The strain displayed the peptidoglycan type A4α l-Lys-d-Asp in the cell wall. Phylogenetic, physiological, biochemical and morphological differences between strain J15A17T and its closest relatives in the genera Cohnella, Fontibacillus and Paenibacillus suggest that strain J15A17T (=KCTC 33759T=MCCC 1H00137T) represents the type strain of a novel species in a new genus within the family Paenibacillaceae, Chengkuizengella sediminis gen. nov. sp. nov.

Two isolates of Gram-reaction-positive, facultatively anaerobic, motile, rod-shaped, endospore-forming bacteria were identified during a survey of the diversity of strains belonging to the genus Bacillus deposited in the Agriculture Research Service Culture Collection. These strains were originally isolated from soil in Evolution Canyon III (Israel) in a survey of ecological diversification. Phylogenetic analysis of the 16S rRNA gene of strains NRRL B-41294T and NRRL B-41327T determined they were closely related to members of the Bacillus licheniformis clade. The genome of each strain was sequenced, and further analysis indicated that the strains represented unique species based on in silico DNA-DNA hybridization analyses. A phylogenomic analysis revealed that NRRL B-41294T and NRRL B-41327T were closely related to the group that includes B. licheniformis. In phenotypic characterization, both NRRL B-41294T and NRRL B-41327T were found to grow at temperatures of between 15 and 60 °C and tolerated up to 12 % NaCl (w/v). The predominant cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0, and peptidoglycan from cell walls contained meso-diaminopimelic acid. The DNA G+C content was 45.7 and 44.3 mol% for NRRL B-41327T and NRRL B-41294T, respectively. Furthermore, each strain had a unique carbon utilization pattern that distinguished it from its nearest phylogenetic neighbours. Based upon the consensus of phylogenetic and phenotypic analyses, we conclude that these strains represent two novel species within the genus Bacillus, for which the name Bacillus swezeyi sp. nov. is proposed, with type strain NRRL B-41294T (=CCUG 70177T), and the name Bacillus haynesii sp. nov. is proposed, with type strain NRRL B-41327T (=CCUG 70178T).

A novel Gram-stain-negative, facultatively anaerobic, yellowish and agar-digesting marine bacterium, designated strain QM50T, was isolated from coastal seawater in an aquaculture site near Qingdao, China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate represented a member of the genus Colwellia and exhibited the highest sequence similarity (97.4 %) to Colwellia aestuarii SMK-10T. Average nucleotide identity (ANI) values based on draft genome sequences between strain QM50T and C. aestuarii KCTC 12480T showed a relatedness of 72.0 % (ANIb) and 85.1 % (ANIm). Cells of strain QM50T were approximately 0.3-0.6×0.8-2.5 µm in size and motile by means of a polar flagellum. Growth occurred in the presence of 1.0-6.0 % (w/v) NaCl (optimum, 2.0-3.0 %), at pH 6.5-8.5 (optimum, pH 7.0) and at 4-37 °C (optimum, 28-30 °C). Strain QM50T was found to contain ubiquinone 8 (Q-8) as the predominant ubiquinone and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C17 : 1ω8c as the main cellular fatty acids. Phosphatidylethanolamine and phosphatidylglycerol were found to be major polar lipids. The DNA G+C content of strain QM50T was determined to be 35.7 mol%. On the basis of phylogenetic and phenotypic data, strain QM50T represents a novel species of the genus Colwellia, for which the name Colwellia agarivorans sp. nov. is proposed. The type strain is QM50T (=KCTC 52273T=MCCC 1H00143T).

A Gram-stain-negative and facultatively anaerobic bacterium, JZ3C34T, was isolated from a saltern in Feicheng, China (36° 8' 24.45″ E 116° 49' 22.46″ N). Cells of strain JZ3C34T were 0.3-0.4 µm wide and 1.5-2.0 µm long, catalase-positive and oxidase-negative. Colonies on modified marine agar 2216 were orange, circular, convex, translucent and approximately 1 mm in diameter after incubation for 96 h at 33 °C. Growth occurred at 20-50 °C (optimally at 33 °C), at pH 6.5-8.5 (optimally at 7.0-8.0) and in the presence of 2-18 % (w/v) NaCl (optimally in 6 % NaCl). Phylogenetic analysis of the 16S rRNA gene indicated that strain JZ3C34T was a member of the family Cryomorphaceae within the order Flavobacteriales and the most closely related species was Owenweeksia hongkongensis DSM 17368T (89.2 % 16S rRNA gene sequence similarity). The major respiratory quinone of strain JZ3C34T was menaquinone MK-7, and the dominant fatty acids were iso-C15 : 0 and iso-C15 : 1 G. The major polar lipids were two unidentified lipids and phosphatidylethanolamine, and the genomic DNA G+C content was 39.6 mol%. Polyphasic taxonomy clearly places the new strain as a novel species within a new genus of the family Cryomorphaceae, for which the name Salibacter halophilus gen. nov., sp. nov. The type strain of Salibacter halophilus is JZ3C34T (=KCTC 52047T=MCCC 1K02288T).

A Gram-strain-positive, facultatively anaerobic, motile, endospore-forming, slightly halophilic bacterium, designated strain 126C4T, was isolated from sediment from the East China Sea. The strain was catalase-positive and oxidase-negative. Optimal growth occurred at 28-30 °C, pH 7.0-7.5 and in the presence of 3-5 % (w/v) NaCl. Phylogenetic analyses, based on 16S rRNA gene sequence comparisons, showed that strain 126C4T was a member of the genus Paraliobacillus, with 16S rRNA gene sequence similarities to Paraliobacillus quinghaiensis YIM-C158T and Paraliobacillus ryukyuensis O15-7T of 96.2 % and 95.3 %, repectively. The DNA G+C content was 39.6 mol%. The strain contained MK-7 as the sole respiratory quinone, anteiso-C15 : 0, C16 : 0, iso-C15 : 0 and iso-C16 : 0 as the major cellular fatty acids, and its polar lipid pattern comprised diphosphatidylglycerol, phosphatidylethanolamine, three glycolipids and four unknown phospholipids. On the basis of its phylogenetic position, phenotypic traits and chemotaxonomic characteristics, it is suggested that strain 126C4T represents a novel species of the genus Paraliobacillus, for which the name Paraliobacillus sediminis sp. nov. is proposed. The type strain is 126C4T (=KCTC 33762T=MCCC 1H00136T).

A novel Gram-stain-negative, rod-shaped, facultatively anaerobic, oxidase-negative and catalase-positive bacterium, designated JZ3C29T, was isolated from a saltern located in Feicheng, PR China. JZ3C29T was tolerant of moderately saline conditions. Optimal growth occurred at 40 °C (range 20-50 °C) and pH 7.5-8.5 (range pH 7.0-9.0) with 8-10 % (w/v) NaCl (range 2-16 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that JZ3C29T shared highest similarity with Gracilimonas tropica CL-CB462T (90.5 %), Gracilimonas mengyeensis YIM J14T (90.5 %) and Gracilimonas rosea CL-KR2T (90.4 %) and less than 90.0 % similarity with other species of the phylum Bacteroidetes. The isolate formed a novel genus-level clade in the recently described family Balneolaceae. The polar lipid profile of the novel isolate consisted of diphosphatidylglycerol, phosphatidylethanolamine, three unidentified glycolipids, four unidentified phospholipids and two unidentified lipids. The dominant cellular fatty acids (>10 %) were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and iso-C15 : 0 and the sole respiratory quinone was menaquinone 7 (MK-7). The DNA G+C content of JZ3C29T was 44.4 mol%. On the basis of these phenotypic and phylogenetic data, JZ3C29T should be classified as representing a novel genus and species within the family Balneolaceae, for which the name Rhodohalobacter halophilus gen. nov., sp. nov. is proposed. The type strain is JZ3C29T (=MCCC 1H00131T=KCTC 52046T=JCM 31413T).

The family Streptomycetaceae, notably species in the genus Streptomyces, have long been the subject of investigation due to their well-known ability to produce secondary metabolites. The emergence of drug resistant pathogens and the relative ease of producing genome sequences has renewed the importance of Streptomyces as producers of new natural products and resulted in revived efforts in isolating and describing strains from novel environments. A previous large study of the phylogeny in the Streptomycetaceae based on 16S rRNA gene sequences provided a useful framework for the relationships among species, but did not always have sufficient resolution to provide definitive identification. Multi-locus sequence analysis of 5 house-keeping genes has been shown to provide improved taxonomic resolution of Streptomyces species in a number of previous reports so a comprehensive study was undertaken to evaluate evolutionary relationships among species within the family Streptomycetaceae where type strains are available in the ARS Culture Collection or genome sequences are available in GenBank. The results of the analysis supported the distinctiveness of Kitasatospora and Streptacidiphilus as validly named genera since they cluster outside of the phylogenetic radiation of the genus Streptomyces. There is also support for the transfer of a number of Streptomyces species to the genus Kitasatospora as well for reducing at least 31 species clusters to a single taxon. The multi-locus sequence database resulting from the study is a useful tool for identification of new isolates and the phylogenetic analysis presented also provides a road map for planning future genome sequencing efforts in the Streptomycetaceae.

Aims: We report the first occurrence of an epizootic of the ascomycete fungus, Isaria tenuipes (teleomorph Cordyceps takaomontana), on the ocola skipper Panoquina ocola (Lepidoptera: Hesperiidae), an insect pest affecting rice in Brazil., Methods and Results: Field surveys in flooded rice fields in the state of Goiás in Brazil were conducted, and a fungal pathogen of a caterpillar pest (P. ocola) was serendipitously found. This fungus inflicted high infection levels (average 86·2%) mainly to the pupal stage during warm, humid growing conditions. Typically, mycosed pupal cadavers produced milky-white to pale yellow synnemata bearing an average of 1·1 ± 0·2 × 10 9 conidia per cadaver. Based on phylogenetic analysis using beta-tubulin gene sequences, we confirmed that all 12 isolates obtained from field-mummified pupae were identifiable as I. tenuipes., Conclusions: Our data expand our knowledge on the host and geographical ranges of this mycopathogen and underscore its epizootic potential to affect a lepidopterous insect pest on rice in Brazil. This finding may facilitate the exploitation of this fungus as a mycoinsecticide., Significance and Impact of the Study: Isaria tenuipes may be used as an effective and environmentally friendly bioinsecticide against agricultural caterpillar pests due to its epizootic potential, as well as explored for medicinal purposes by pharmaceutical industry., (© 2016 The Society for Applied Microbiology.)

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. destructans IMPORTANCE 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., (Copyright © 2017 American Society for Microbiology.)