Antifungal Activity of Selected Indigenous Pseudomonas and Bacillus from the Soybean Rhizosphere

The purpose of this study was to isolate and select indigenous soil Pseudomonas and Bacillus bacteria capable of developing multiple mechanisms of action related to the biocontrol of phytopathogenic fungi affecting soybean crops. The screening procedure consisted of antagonism tests against a panel of phytopathogenic fungi, taxonomic identification, detection by PCR of several genes related to antifungal activity, in vitro detection of the antifungal products, and root colonization assays. Two isolates, identified and designated as Pseudomonas fluorescens BNM296 and Bacillus amyloliquefaciens BNM340, were selected for further studies. These isolates protected plants against the damping-off caused by Pythium ultimum and were able to increase the seedling emergence rate after inoculation of soybean seeds with each bacterium. Also, the shoot nitrogen content was higher in plants when seeds were inoculated with BNM296. The polyphasic approach of this work allowed us to select two indigenous bacterial strains that promoted the early development of soybean plants

The Sloan Great Wall. Morphology and galaxy content

We present the results of the study of the morphology and galaxy content of the Sloan Great Wall (SGW). We use the luminosity density field to determine superclusters in the SGW, and the fourth Minkowski functional V_3 and the morphological signature (the K_1-K_2 shapefinders curve) to show the different morphologies of the SGW, from a single filament to a multibranching, clumpy planar system. The richest supercluster in the SGW, SCl~126 and especially its core resemble a very rich filament, while another rich supercluster in the SGW, SCl~111, resembles a "multispider" - an assembly of high density regions connected by chains of galaxies. Using Minkowski functionals we study the substructure of individual galaxy populations determined by their color in these superclusters. We assess the statistical significance of the results with the halo model and smoothed bootstrap. We study the galaxy content and the properties of groups of galaxies in two richest superclusters of the SGW, paying special attention to bright red galaxies (BRGs) and to the first ranked galaxies in SGW groups. About 1/3 of BRGs are spirals. The scatter of colors of elliptical BRGs is smaller than that of spiral BRGs. About half of BRGs and of first ranked galaxies in groups have large peculiar velocities. Groups with elliptical BRGs as their first ranked galaxies populate superclusters more uniformly than the groups, which have a spiral BRG as its first ranked galaxy. The galaxy and group content of the core of the supercluster SCl~126 shows several differences in comparison with the outskirts of this supercluster and with the supercluster SCl~111. Our results suggest that the formation history and evolution of individual neighbour superclusters in the SGW has been different.Comment: Comments: 26 pages, 20 figures, accepted for publication in Ap

Nutritional therapies for mental disorders

According to the Diagnostic and Statistical Manual of Mental Disorders, 4 out of the 10 leading causes of disability in the US and other developed countries are mental disorders. Major depression, bipolar disorder, schizophrenia, and obsessive compulsive disorder (OCD) are among the most common mental disorders that currently plague numerous countries and have varying incidence rates from 26 percent in America to 4 percent in China. Though some of this difference may be attributable to the manner in which individual healthcare providers diagnose mental disorders, this noticeable distribution can be also explained by studies which show that a lack of certain dietary nutrients contribute to the development of mental disorders. Notably, essential vitamins, minerals, and omega-3 fatty acids are often deficient in the general population in America and other developed countries; and are exceptionally deficient in patients suffering from mental disorders. Studies have shown that daily supplements of vital nutrients often effectively reduce patients' symptoms. Supplements that contain amino acids also reduce symptoms, because they are converted to neurotransmitters that alleviate depression and other mental disorders. Based on emerging scientific evidence, this form of nutritional supplement treatment may be appropriate for controlling major depression, bipolar disorder, schizophrenia and anxiety disorders, eating disorders, attention deficit disorder/attention deficit hyperactivity disorder (ADD/ADHD), addiction, and autism. The aim of this manuscript is to emphasize which dietary supplements can aid the treatment of the four most common mental disorders currently affecting America and other developed countries: major depression, bipolar disorder, schizophrenia, and obsessive compulsive disorder (OCD)

Las barreras de defensa primarias del mandarino 'Okitsu' son la principal causa de la resistencia a Xanthomonas citri subsp. citri

Poster presented at the VIII Encuentro para Latino América y el Caribe de Biotecnología REDBIO Argentina 2013, held in Mar de Plata on November 18-22, 2013. More details at http://redbioargentina2013.com.ar/.Pruebas de patogenicidad de X. citri en hojas de mandarinos. Bajo condiciones controladas se seleccionaron brotes nuevos de aproximadamente 1 cm de tamaño y con al menos 5 hojas. Cada hoja del brote seleccionado, comenzando por la más alejada del ápice, fue inoculada a los 15, 18, 22, 25 y 27 días de edad, respectivamente. Las suspensiones bacterianas se inocularon en las hojas usando dos métodos: AInfiltración y, B- Aspersión, respectivamente. Los valores están expresados como la media + la desviación estándar. Los datos marcados con asterisco difieren significativamente entre ambos cultivares de acuerdo al test t de Student, P< 0,05.Peer reviewe

The histone-like protein HupB influences biofilm formation and virulence in Xanthomonas citri ssp. citri through the regulation of flagellar biosynthesis

Citrus canker is an important disease of citrus, whose causal agent is the bacterium Xanthomonas citri ssp. citri (Xcc). In previous studies, we found a group of Xcc mutants, generated by the insertion of the Tn5 transposon, which showed impaired ability to attach to an abiotic substrate. One of these mutants carries the Tn5 insertion in hupB, a gene encoding a bacterial histone-like protein, homologue to the β-subunit of the Heat-Unstable (HU) nucleoid protein of Escherichia coli. These types of protein are necessary to maintain the bacterial nucleoid organization and the global regulation of gene expression. Here, we characterized the influence of the mutation in hupB regarding Xcc biofilm forma tion and virulence. The mutant strain hupB was incapable of swimming in soft agar, whereas its complemented strain partially recovered this phenotype. Electron microscope imaging revealed that impaired motility of hupB was a consequence of the absence of the flagellum. Comparison of the expression of flagellar genes between the wild-type strain and hupB showed that the mutant exhibited decreased expression of fliC (encoding flagellin). The hupB mutant also displayed reduced virulence compared with the wild-type strain when they were used to infect Citrus lemon plants using different infection methods. Our results therefore show that the histone-like protein HupB plays an essential role in the pathogenesis of Xcc through the regulation of biofilm formation and biosynthesis of the flagellum.Fil: Conforte, Valeria P. Instituto de Ciencia y Tecnología Dr. César Milstein (ICT – CONICET - Fundación Pablo Cassará); Argentina.Fil: Malamud, Florencia. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentina.Fil: Yaryura, Pablo M. Universidad de Villa María. Centro de Investigaciones y Transferencia de Villa María (CIT - CONICET); Argentina.Fil: Toum Terrones, Laila. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; Argentina.Fil: Toum Terrones, Laila. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA - CONICET); Argentina.Fil: Torres, Pablo S. Instituto de Ciencia y Tecnología Dr. César Milstein (ICT – CONICET - Fundación Pablo Cassará); Argentina.Fil: De Pino, Verónica. Instituto de Ciencia y Tecnología Dr. César Milstein (ICT – CONICET - Fundación Pablo Cassará); Argentina.Fil: Chazarreta, Cristian N. Instituto de Ciencia y Tecnología Dr. César Milstein (ICT – CONICET - Fundación Pablo Cassará); Argentina.Fil: Gudesblat, Gustavo E. Instituto de Tecnología Agroindustrial del Noroeste Argentino (ITANOA – CONICET -Estación Experimental Agroindustrial Obispo Colombres (EEAOC); Argentina.Fil: Castagnaro, Atilio P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; Argentina.Fil: Castagnaro, Atilio P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA - CONICET); Argentina.Fil: Marano, María Rosa. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Departamento de Microbiología; Argentina.Fil: Marano, María Rosa. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR -CONICET); Argentina.Fil: Vojnov, Adrián A. Instituto de Ciencia y Tecnología Dr. César Milstein (ICT – CONICET - Fundación Pablo Cassará); Argentina

Associations of dwarf galaxies in a λCDM Universe

Associations of dwarf galaxies are loose systems composed exclusively of dwarf galaxies. These systems were identified in the Local Volume for the first time more than 30 yr ago. We study these systems in the cosmological framework of the λ cold dark matter (λCDM) model.We consider the Small MultiDark Planck simulation and populate its dark matter haloes by applying the semi-analytic model of galaxy formation SAG. We identify galaxy systems using a friends-of-friends algorithm with a linking length equal to b = 0.4Mpc h-1to reproduce the size of dwarf galaxy associations detected in the Local Volume. Our samples of dwarf systems are built up removing those systems that have one or more galaxies with stellar mass larger than a maximum thresholdMmax.We analyse three different samples defined by log10(Mmax[M⊙ h-1]) = 8.5, 9.0, and 9.5. On average, our systems have typical sizes of ∼ 0.2Mpc h-1, velocity dispersion of ∼ 30km s-1, and estimated total mass of ∼ 1011M⊙ h-1. Such large typical sizes suggest that individual members of a given dwarf association reside in different dark matter haloes and are generally not substructures of any other halo. Indeed, in more than 90 per cent of our dwarf systems their individual members inhabit different dark matter haloes, while only in the remaining 10 per cent members do reside in the same halo. Our results indicate that the λCDM model can naturally reproduce the existence and properties of dwarf galaxies' associations without much difficulty. © 2020 Oxford University Press. All rights reserved.Immediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]