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1.
Artículo en Inglés | MEDLINE | ID: mdl-38841989

RESUMEN

Opinion 130 deals with a Request for an Opinion asking the Judicial Commission to clarify whether the genus name Rhodococcus Zopf 1891 (Approved Lists 1980) is illegitimate. The Request is approved and an answer is given. The name Rhodococcus Zopf 1891 (Approved Lists 1980) is illegitimate because it is a later homonym of the validly published cyanobacterial name Rhodococcus Hansgirg 1884. The Judicial Commission also clarifies that it has the means to resolve such cases by conserving a name over an earlier homonym. It is concluded that the name Rhodococcus Zopf 1891 (Approved Lists 1980) is significantly more important than the name Rhodococcus Hansgirg 1884 and therefore the former is conserved over the latter. This makes the name Rhodococcus Zopf 1891 (Approved Lists 1980) legitimate.


Asunto(s)
Rhodococcus , Terminología como Asunto , Rhodococcus/clasificación
2.
Med Vet Entomol ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747253

RESUMEN

Accurate knowledge of blood meal hosts of different mosquito species is critical for identifying potential vectors and establishing the risk of pathogen transmission. We compared the performance of Miseq next generation sequencing approach relative to conventional Sanger sequencing approach in identification of mosquito blood meals using genetic markers targeting the 12S rRNA and cytochrome oxidase I (COI) genes. We analysed the blood meals of three mosquito vector species (Aedes aegypti, Aedes simpsoni s.l. and Culex pipiens s.l.) collected outdoors, and compared the frequency of single- versus multiple-blood feeding. Single host blood meals were mostly recovered for Sanger-based sequencing of the mitochondrial 12S rRNA gene, whereas Miseq sequencing employing this marker and the COI marker detected both single and multiple blood meal hosts in individual mosquitoes. Multiple blood meals (two or more hosts) which mostly included humans were detected in 19%-22.7% of Ae. aegypti samples. Most single host blood meals for this mosquito species were from humans (47.7%-57.1%) and dogs (9.1%-19.0%), with livestock, reptile and rodent hosts collectively accounting for 4.7%-28.9% of single host blood meals. The frequency of two or more host blood meals in Ae. simpsoni s.l. was 26.3%-45.5% mostly including humans, while single host blood meals were predominantly from humans (31.8%-47.4%) with representation of rodent, reptile and livestock blood meals (18.2%-68.2%). Single host blood meals from Cx. pipiens s.l. were mostly from humans (27.0%-39.4%) and cows (11.5%-27.36%). Multiple blood meal hosts that mostly included humans occurred in 21.2%-24.4% of Cx. pipiens s.l. samples. Estimated human blood indices ranged from 53%-76% for Ae. aegypti, 32%-82% for Ae. simpsoni s.l. and 26%-61% for Cx. pipiens s.l. and were consistently lower for Sanger-based sequencing approach compared to Miseq-based sequencing approach. These findings demonstrate that Miseq sequencing approach is superior to Sanger sequencing approach as it can reliably identify mixed host blood meals in a single mosquito, improving our ability to understand the transmission dynamics of mosquito-borne pathogens.

3.
FEMS Microbes ; 5: xtae002, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450098

RESUMEN

Container aquatic habitats host a community of aquatic insects, primarily mosquito larvae that browse on container surface microbial biofilm and filter-feed on microorganisms in the water column. We examined how the bacterial communities in these habitats respond to feeding by larvae of two container-dwelling mosquito species, Culex pipiens and Cx. restuans. We also investigated how the microbiota of these larvae is impacted by intra- and interspecific interactions. Microbial diversity and richness were significantly higher in water samples when mosquito larvae were present, and in Cx. restuans compared to Cx. pipiens larvae. Microbial communities of water samples clustered based on the presence or absence of mosquito larvae and were distinct from those of mosquito larvae. Culex pipiens and Cx. restuans larvae harbored distinct microbial communities when reared under intraspecific conditions and similar microbial communities when reared under interspecific conditions. These findings demonstrate that mosquito larvae play a major role in structuring the microbial communities in container habitats and that intra- and interspecific interactions in mosquito larvae may shape their microbiota. This has important ecological and public health implications since larvae of the two mosquito species are major occupants of container habitats while the adults are vectors of West Nile virus.

4.
Front Microbiol ; 15: 1336515, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529179

RESUMEN

Crop production often faces challenges from plant diseases, and biological control emerges as an effective, environmentally friendly, cost-effective, and sustainable alternative to chemical control. Wheat blast disease caused by fungal pathogen Magnaporthe oryzae Triticum (MoT), is a potential catastrophic threat to global food security. This study aimed to identify potential bacterial isolates from rice and wheat seeds with inhibitory effects against MoT. In dual culture and seedling assays, three bacterial isolates (BTS-3, BTS-4, and BTLK6A) demonstrated effective suppression of MoT growth and reduced wheat blast severity when artificially inoculated at the seedling stage. Genome phylogeny identified these isolates as Bacillus subtilis (BTS-3) and B. velezensis (BTS-4 and BTLK6A). Whole-genome analysis revealed the presence of genes responsible for controlling MoT through antimicrobial defense, antioxidant defense, cell wall degradation, and induced systemic resistance (ISR). Taken together, our results suggest that the suppression of wheat blast disease by seed endophytic B. subtilis (BTS-3) and B. velezensis (BTS-4 and BTLK6A) is liked with antibiosis and induced systemic resistance to wheat plants. A further field validation is needed before recommending these endophytic bacteria for biological control of wheat blast.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38252201

RESUMEN

Clostridium tyrobutyricum strain NRRL B-67062 was previously isolated from an ethanol production facility and shown to produce high yields of butyric acid. In addition, the cell-free supernatant of the fermentation broth from NRRL B-67062 contained antibacterial activity against certain Gram-positive bacteria. To determine the source of this antibacterial activity, we report the genome and genome mining of this strain. The complete genome of NRRL B-67062 showed one circular chromosome of 3,242,608 nucleotides, 3114 predicted coding sequences, 79 RNA genes, and a G+C content of 31.0%. Analyses of the genome data for genes potentially associated with antimicrobial features were sought after by using BAGEL-4 and anti-SMASH databases. Among the leads, a polypeptide of 66 amino acids (PEG 446) contains the DUF4177 domain, which is an uncharacterized highly conserved domain (pfam13783). The cloning and expression of the peg446 gene in Escherichia coli and Bacillus subtilis confirmed the antibacterial property against Lactococcus lactis LM 0230, Limosilactobacillus fermentum 0315-25, and Listeria innocua NRRL B-33088 by gel overlay and well diffusion assays. Molecular modeling suggested that PEG 446 contains one alpha-helix and three anti-parallel short beta-sheets. These results will aid further functional studies and facilitate simultaneously fermentative production of both butyric acid and a putative bacteriocin from agricultural waste and lignocellulosic biomass materials.

6.
Sci Rep ; 13(1): 14292, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37653049

RESUMEN

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.


Asunto(s)
Antibacterianos , Chromobacterium , Chromobacterium/genética , Filogenia , Antibacterianos/farmacología , Brasil , Escherichia coli , Pseudomonas
7.
Antonie Van Leeuwenhoek ; 116(7): 615-630, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37138159

RESUMEN

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.


Asunto(s)
Arabidopsis , Bacillaceae , Ácidos Indolacéticos/metabolismo , Desarrollo de la Planta , Bacterias/metabolismo , Bacillaceae/genética , Bacillaceae/metabolismo , Arabidopsis/metabolismo , Plantas/metabolismo , Raíces de Plantas/microbiología
8.
Nicotine Tob Res ; 25(3): 581-585, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36070398

RESUMEN

INTRODUCTION: E-cigarette advertising exposure is linked to e-cigarette initiation and use. Thus, monitoring trends in e-cigarette advertising practices is important to understand e-cigarette use patterns observed over recent years. AIMS AND METHODS: E-cigarette advertising expenditures (January 2016-July 2021; Numerator Ad Intel) for 154 U.S. market areas were harmonized with U.S. Census sociodemographic data through Nielsen zip code designations by market area. Descriptive statistics and multivariable linear regressions were used to examine trends in e-cigarette advertising expenditures across media outlets and associations between sociodemographic characteristics and e-cigarette advertising over time. RESULTS: E-cigarette advertising expenditures peaked in 2018/2019, followed by a sharp decline in 2020. Expenditures were concentrated primarily on print (58.9%), TV (20.6%), and radio (14.4%). Major print outlets were Sports Illustrated, Rolling Stone, and Star magazines. Top TV channels were AMC, Investigation Discovery, and TBS. TV advertisements were purchased commonly during popular movies and TV series (eg King of Queens, Everybody Loves Raymond, The Walking Dead). Higher expenditures were associated with U.S. market areas that had (1) a larger percentage of non-rural zip codes (radio), (2) smaller male populations (radio), and (3) larger White or Caucasian, Black or African American, American Indian or Alaska Native, Asian, and Other or Multiracial populations (radio, print, online display, and online video). CONCLUSIONS: E-cigarette companies advertised in print magazines geared toward males and youth and young adults, radio commercials focused in urban areas with smaller male populations, and nationwide TV commercials. Declines in e-cigarette advertising expenditures in 2020 demonstrate the potential impact that federal policies may have on protecting populations who are at higher risk for tobacco use from predatory advertising practices. IMPLICATIONS: E-cigarette advertising exposure is associated with the initiation and use of e-cigarettes. This study shows how e-cigarette marketing expenditures in the United States may have targeted specific consumers (eg youth and young adults) between 2016 and 2021. The precipitous drop in advertising expenditures across all outlets during early 2020 corresponds with the implementation of the Tobacco 21 federal policy, the federal enforcement policy to remove most unauthorized flavored e-cigarette cartridges from the U.S. market, preparations for FDA's premarket review of e-cigarette products, and the decision by several TV broadcast companies to stop showing e-cigarette ads. The potential impact of federal policies may have far-reaching implications for protecting populations who are at high risk for tobacco use and its health consequences.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Adolescente , Adulto Joven , Masculino , Humanos , Estados Unidos/epidemiología , Gastos en Salud , Mercadotecnía , Uso de Tabaco
9.
Front Plant Sci ; 13: 983127, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36275544

RESUMEN

Microbial crop protection products based on Trichoderma have the ability to display multifunctional roles in plant protection, such as pathogen parasitism, enhance nutrient availability and stimulate plant growth, and these traits can be used to enhance the overall agronomic performance of a variety of crops. In the current study, we explored the multifunctional potential of two indigenous Brazilian strains of Trichoderma (T. asperelloides CMAA 1584 and T. lentiforme CMAA 1585) for their capability of controlling Sclerotinia sclerotiorum, a key plant pathogen of cotton, and for their ability of growth promotion in cotton plants (Gossypium hirsutum). Both strains were able to solubilize mineral phosphorus (CaHPO4), to release volatile organic compounds that impaired the mycelial growth of S. sclerotiorum, and to promote the growth of cotton plants under greenhouse conditions. In dual culture, Trichoderma strains reduced the growth rate and the number of sclerotia formed by S. sclerotiorum. By treating sclerotia with conidial suspensions of these Trichoderma strains, a strong inhibition of the myceliogenic germination was observed, as a result of the marked mycoparasitic activity exerted on the sclerotia. The parasitism over S. sclerotiorum was more effective with T. asperelloides CMAA 1584, whilst the biostimulant effects on cotton growth were more pronounced with T. lentiforme CMAA 1585, which also showed a higher capacity of phosphate solubilization. Thus, T. asperelloides CMAA 1584 displays higher efficiency in controlling S. sclerotiorum, while T. lentiforme CMAA 1585 is more suitable as a biostimulant due to its ability to promote growth in cotton plants. Overall, these Trichoderma strains may be used in mixture to provide both pathogen control and promotion of plant growth, and this strategy will support growers in minimizing the use of synthetic fertilizers and fungicides against white mold in cotton crops.

10.
Microbiol Resour Announc ; 11(10): e0041722, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36154195

RESUMEN

We report the draft genome sequences of four Chromobacterium strains. This report includes the draft genome sequences of four environmental strains, isolated from surface waters in Brazil.

11.
Extremophiles ; 26(2): 25, 2022 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-35842547

RESUMEN

The draft genome sequences of five archaeal strains, isolated from Sfax solar saltern sediments and affiliated with Halobacterium salinarum, were analyzed in order to reveal their adaptive strategies to live in hypersaline environments polluted with heavy metals. The genomes of the strains (named AS1, AS2, AS8, AS11, and AS19) are found to contain 2,060,688; 2,467,461; 2,236,624; 2,432,692; and 2,428,727 bp respectively, with a G + C content of 65.5, 66.0, 67.0, and 66.2%. The majority of these genes (43.69-55.65%) are annotated as hypothetical proteins. Growth under osmotic stress is possible by genes coding for potassium uptake, sodium efflux, and kinases, as well as stress proteins, DNA repair systems, and proteasomal components. These strains harbor many genes responsible for metal transport/resistance, such as: copper-translocating P-type ATPases, ABC transporter, and cobalt-zinc-cadmium resistance protein. In addition, detoxification enzymes and secondary metabolites are also identified. The results show strain AS1, as compared to the other strains, is more adapted to heavy metals and may be used in the bioremediation of multi-metal contaminated environments. This study highlights the presence of several commercially valuable bioproducts (carotenoids, retinal proteins, exopolysaccharide, stress proteins, squalene, and siderophores) and enzymes (protease, sulfatase, phosphatase, phosphoesterase, and chitinase) that can be used in many industrial applications.


Asunto(s)
Halobacterium salinarum , Metales Pesados , Biodegradación Ambiental , Genómica , Halobacterium salinarum/genética , Proteínas de Choque Térmico
12.
Addict Behav ; 127: 107210, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34959076

RESUMEN

INTRODUCTION: The study identified groups of JUUL using young adults based on their use patterns and compared harm perceptions, JUUL dependence, and other tobacco product use among these groups. METHODS: Online cross-sectional survey data were gathered in March 2019 from 667 undergraduate students who used JUUL weekly (50.4% females, average age: 20.3 years) at a southwest U.S. university. RESULTS: Latent class analysis identified four groups of young adults who used JUUL: 1) Light Social JUUL Using Young Adults (LS, 52.5%) who used JUUL occasionally with friends when drinking alcohol, 2) Daily Sensation Seekers (DSS, 16.2%) who used JUUL daily with alcohol, 3) Daily Activity Driven JUUL Using Young Adults (DAD, 26.0%) who used JUUL daily while drinking, watching media, or studying, and 4) Daily All Occasion JUUL Using Young Adults (DAO, 5.3%) who used JUUL heavily, daily and in various occasions. While all four groups reported some extent of JUUL dependence, DAO reported the highest dependence and were more likely than LS to have used cigarettes and other e-cigarettes besides JUUL. They also tended to believe different pod flavors could cause different types of lung damage while the other groups were unsure/disagreed with this belief. LS were more likely than DSS and DAD to believe that JUUL use indicated openness to new experiences. CONCLUSION: Young adults with different JUUL use patterns perceived JUUL harms differently and faced varied risks of JUUL dependence and other tobacco product use. Effective cessation interventions should be adapted to meet the needs of these groups.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Tabaquismo , Vapeo , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Adulto Joven
13.
Sci Rep ; 11(1): 14406, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34257327

RESUMEN

Insecticide resistance has emerged as a persistent threat to the fight against vector-borne diseases. We compared the gut microbiota of permethrin-selected (PS) strain of Aedes aegypti relative to the parent (KW) strain from Key West, Florida. Bacterial richness but not diversity was significantly higher in PS strain compared to KW strain. The two mosquito strains also differed in their gut microbial composition. Cutibacterium spp., Corynebacterium spp., Citricoccus spp., Leucobacter spp., Acinetobacter spp., Dietzia spp., and Anaerococcus spp. were more abundant in PS strain than in KW strain. In contrast, Sphingomonas spp., Aquabacterium spp., Methylobacterium spp., Flavobacterium spp., Lactobacillus spp., unclassified Burkholderiaceae and unclassified Nostocaceae were more abundant in KW strain compared to PS strain. PS strain was enriched with propionate metabolizers, selenate reducers, and xylan, chitin, and chlorophenol degraders while KW strain was enriched with sulfur oxidizers, sulfur metabolizers, sulfate reducers and naphthalene and aromatic hydrocarbons degraders. These findings demonstrate an association between the gut microbiota and insecticide resistance in an important vector species and sets the foundation for future studies to investigate the contribution of gut microbiota to evolution of insecticide resistance in disease vectors.


Asunto(s)
Aedes , Microbioma Gastrointestinal , Permetrina , Animales , Mosquitos Vectores
14.
Plant Physiol Biochem ; 165: 217-227, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34058513

RESUMEN

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 Ca2+ 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.


Asunto(s)
Bacillus , Solanum lycopersicum , Antioxidantes , Estrés Salino , Estrés Fisiológico
15.
Sci Rep ; 11(1): 10971, 2021 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-34040020

RESUMEN

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) × 107 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.


Asunto(s)
Escarabajos/microbiología , Microsporidia no Clasificados/aislamiento & purificación , Animales , Brasil , Eucalyptus , Hemolinfa/microbiología , Microsporidia no Clasificados/clasificación , Microsporidia no Clasificados/genética , Microsporidia no Clasificados/patogenicidad , Filogenia , ARN de Hongos/genética , ARN Ribosómico/genética , Especificidad de la Especie
16.
Plant Cell Rep ; 40(7): 1199-1213, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33983490

RESUMEN

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.


Asunto(s)
Inoculantes Agrícolas/fisiología , Bacillus/fisiología , Estrés Salino/fisiología , Solanum lycopersicum/fisiología , Antioxidantes/metabolismo , Carotenoides/metabolismo , Membrana Celular/metabolismo , Clorofila/metabolismo , Germinación , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Metales/metabolismo , Peroxidasa/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plantones/crecimiento & desarrollo
17.
Front Cell Infect Microbiol ; 11: 644372, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33842391

RESUMEN

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.


Asunto(s)
Beauveria , Beauveria/genética , Medios de Cultivo , Fermentación , Perfilación de la Expresión Génica , Glucosa , Esporas Fúngicas
18.
Sci Rep ; 11(1): 7910, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-33846445

RESUMEN

Mosquito bacterial communities are essential in mosquito biology, and knowing the factors shaping these bacterial communities is critical to their application in mosquito-borne disease control. This study investigated how the larval environment influences the bacterial communities of larval stages of two container-dwelling mosquito species, Aedes triseriatus, and Aedes japonicus. Larval and water samples were collected from tree holes and used tires at two study sites, and their bacteria characterized through MiSeq sequencing of the 16S rRNA gene. Bacterial richness was highest in Ae. japonicus, intermediate in Ae. triseriatus, and lowest in water samples. Dysgonomonas was the dominant bacterial taxa in Ae. triseriatus larvae; the unclassified Comamonadaceae was dominant in water samples from waste tires, while Mycobacterium and Carnobacterium, dominated Ae. japonicus. The two mosquito species harbored distinct bacterial communities that were different from those of the water samples. The bacterial communities also clustered by habitat type (used tires vs. tree holes) and study site. These findings demonstrate that host species, and the larval sampling environment are important determinants of a significant component of bacterial community composition and diversity in mosquito larvae and that the mosquito body may select for microbes that are generally rare in the larval environment.


Asunto(s)
Aedes/microbiología , Bacterias/metabolismo , Análisis de Varianza , Animales , Bacterias/clasificación , Biodiversidad , Análisis Discriminante , Larva/microbiología , Microbiología del Agua
19.
Parasit Vectors ; 14(1): 83, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33509255

RESUMEN

BACKGROUND: The guts of blood-sucking insects host a community of bacteria that can shift dramatically in response to biotic and abiotic factors. Identifying the key factors structuring these microbial communities has important ecological and epidemiological implications. METHODS: We used the yellow fever mosquito, Aedes aegypti, to investigate the impact of mixed blood meals on gut microbiota of vector mosquitoes. Adult females were experimentally fed on sugar or blood from chicken, rabbit or a mixture of chicken and rabbit blood, and their gut microbiota were characterized using 16S rRNA gene amplification and MiSeq sequencing. RESULTS: The gut bacterial communities of mosquitoes fed on the three blood meal treatments clustered separately, suggesting that host species identity and mixed blood-feeding are key determinants of gut bacterial community composition in mosquitoes. Mixed blood meal had a synergistic effect on both operational taxonomic unit (OTU) richness and the Shannon diversity index, suggesting that mixed blood-feeding can offset the nutritional deficit of blood meals from certain host species. The microbial communities observed in this study were distinct from those identified from similarly fed Ae. aegypti from our previous study. CONCLUSIONS: These findings demonstrate that vector host-feeding preferences can influence gut microbial composition and diversity, which could potentially impact pathogen acquisition and transmission by the vector. The results also demonstrate that different microenvironmental conditions within the laboratory may play an important role in structuring the microbial communities of independently reared mosquito colonies.


Asunto(s)
Aedes , Conducta Alimentaria , Microbioma Gastrointestinal/genética , Aedes/microbiología , Aedes/fisiología , Animales , Bacterias/clasificación , Sangre , Pollos , Genes Bacterianos , Comidas , Metagenómica/métodos , Microbiota , Mosquitos Vectores/microbiología , Mosquitos Vectores/fisiología , ARN Ribosómico 16S/genética , Conejos
20.
Antonie Van Leeuwenhoek ; 114(1): 37-44, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33392934

RESUMEN

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).


Asunto(s)
Fosfolípidos , Zea mays , Bacillales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
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