Universidade Estadual de Londrina

About: Universidade Estadual de Londrina is a education organization based out in Londrina, Brazil. It is known for research contribution in the topics: Population & Toxoplasma gondii. The organization has 13052 authors who have published 19291 publications receiving 212123 citations.

Genome-wide analysis of the Hsp20 gene family in soybean: comprehensive sequence, genomic organization and expression profile analysis under abiotic and biotic stresses

Abstract: The Hsp 20 genes are associated with stress caused by HS and other abiotic factors, but have recently been found to be associated with the response to biotic stresses. These genes represent the most abundant class among the HSPs in plants, but little is known about this gene family in soybean. Because of their apparent multifunctionality, these proteins are promising targets for developing crop varieties that are better adapted to biotic and abiotic stresses. Thus, in the present study an in silico identification of GmHsp 20 gene family members was performed, and the genes were characterized and subjected to in vivo expression analysis under biotic and abiotic stresses. A search of the available soybean genome databases revealed 51 gene models as potential GmHsp 20 candidates. The 51 GmHsp 20 genes were distributed across a total of 15 subfamilies where a specific predicted secondary structure was identified. Based on in vivo analysis, only 47 soybean Hsp 20 genes were responsive to heat shock stress. Among the GmHsp 20 genes that were potentials HSR, five were also cold-induced, and another five, in addition to one GmAcd gene, were responsive to Meloidogyne javanica infection. Furthermore, one predicted GmHsp 20 was shown to be responsive only to nematode infection; no expression change was detected under other stress conditions. Some of the biotic stress-responsive GmHsp 20 genes exhibited a divergent expression pattern between resistant and susceptible soybean genotypes under M. javanica infection. The putative regulatory elements presenting some conservation level in the GmHsp 20 promoters included HSE, W-box, CAAT box, and TA-rich elements. Some of these putative elements showed a unique occurrence pattern among genes responsive to nematode infection. The evolution of Hsp 20 family in soybean genome has most likely involved a total of 23 gene duplications. The obtained expression profiles revealed that the majority of the 51 GmHsp 20 candidates are induced under HT, but other members of this family could also be involved in normal cellular functions, unrelated to HT. Some of the GmHsp 20 genes might be specialized to respond to nematode stress, and the predicted promoter structure of these genes seems to have a particular conserved pattern related to their biological function.

Which Amino Acids Should Be Used in Prebiotic Chemistry Studies

Abstract: The adsorption of amino acids on minerals and their condensation under conditions that resemble those of prebiotic earth is a well studied subject. However, which amino acids should be used in these experiments is still an open question. The main goal of this review is to attempt to answer this question. There were two sources of amino acids for the prebiotic earth: (1) exogenous—meaning that the amino acids were synthesized outside the earth and delivered to our planet by interplanetary dust particles (IDPs), meteorites, comets, etc. and (2) endogenous—meaning that they were synthesized on earth in atmospheric mixtures, hydrothermal vents, etc. For prebiotic chemistry studies, the use of a mixture of amino acids from both endogenous and exogenous sources is suggested. The exogenous contribution of amino acids to this mixture is very different from the average composition of proteins, and contains several non-protein amino acids. On the other hand, the mixture of amino acids from endogenous sources is seems to more closely resemble the amino acid composition of terrestrial proteins.

Genomic basis of broad host range and environmental adaptability of Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 which are used in inoculants for common bean (Phaseolus vulgaris L.)

Abstract: Background Rhizobium tropici CIAT 899 and Rhizobium sp. PRF 81 are α-Proteobacteria that establish nitrogen-fixing symbioses with a range of legume hosts. These strains are broadly used in commercial inoculants for application to common bean (Phaseolus vulgaris) in South America and Africa. Both strains display intrinsic resistance to several abiotic stressful conditions such as low soil pH and high temperatures, which are common in tropical environments, and to several antimicrobials, including pesticides. The genetic determinants of these interesting characteristics remain largely unknown.

Synergistic and Additive Effect of Oregano Essential Oil and Biological Silver Nanoparticles against Multidrug-Resistant Bacterial Strains.

Abstract: Bacterial resistance to conventional antibiotics has become a clinical and public health problem, making therapeutic decisions more challenging Plant compounds and nanodrugs have been proposed as potential antimicrobial alternatives Studies have shown that oregano (Origanum vulgare) essential oil (OEO) and silver nanoparticles have potent antibacterial activity, also against multidrug-resistant strains; however, the strong organoleptic characteristics of OEO and the development of resistance to these metal nanoparticles can limit their use This study evaluated the antibacterial effect of a two-drug combination of biologically synthesized silver nanoparticles (bio-AgNP), produced by Fusarium oxysporum, and OEO against Gram-positive and Gram-negative bacteria, including multidrug-resistant strains OEO and bio-AgNP showed bactericidal effects against all 17 strains tested, with minimal inhibitory concentrations (MIC) ranging from 0298 to 1193 mg/mL and 625 to 250 μM, respectively Time-kill curves indicated that OEO acted rapidly (within 10 min), while the metallic nanoparticles took 4 h to kill Gram-negative bacteria and 24 h to kill Gram-positive bacteria The combination of the two compounds resulted in a synergistic or additive effect, reducing their MIC values and reducing the time of action compared to bio-AgNP used alone, ie, 20 min for Gram-negative bacteria and 7 h for Gram-positive bacteria Scanning electron microscopy (SEM) revealed similar morphological alterations in Staphylococcus aureus (non-methicillin-resistant S aureus, non-MRSA) cells exposed to three different treatments (OEO, bio-AgNP and combination of the two), which appeared cell surface blebbing Individual and combined treatments showed reduction in cell density and decrease in exopolysaccharide matrix compared to untreated bacterial cells It indicated that this composition have an antimicrobial activity against S aureus by disrupting cells Both compounds showed very low hemolytic activity, especially at MIC levels This study describes for the first time the synergistic and additive interaction between OEO and bio-AgNP produced by F oxysporum against multidrug-resistant bacteria, such as MRSA, and β-lactamase- and carbapenemase-producing Escherichia coli and Acinetobacter baumannii strains These results indicated that this combination can be an alternative in the control of infections with few or no treatment options