Publications by authors named "Fiorela Nievas"

Article Synopsis
  • - The research details the full genome sequence of a specific bacterial strain, sp. 62B, found in the root nodules of peanut plants in central Argentina.
  • - The total genome size is 8.15 megabase pairs (Mbp), which is organized into a main chromosome of 7.29 Mbp and a smaller plasmid of 0.86 Mbp.
  • - This study contributes to our understanding of beneficial bacteria associated with peanut plants and their genetic makeup.
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Salinity inhibits plant growth by affecting physiological processes, but soil microorganisms like plant growth-promoting rhizobacteria (PGPR) can alleviate abiotic stress and enhance crop productivity. However, it should be noted that rhizobacteria employ different approaches to deal with salt stress conditions and successfully colonize roots. The objective of this study was to investigate the effect of salt stress on bacterial survival mechanisms such as mobility, biofilm formation, and the autoaggregation capacity of three plant growth-promoting strains: SJ04, WCS417r, and GB03.

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Article Synopsis
  • The study presents the full genome sequence of the rhizobial strain R31, which is widely used as a commercial inoculant for chickpeas in Argentina.
  • The genome has a total size of 7.25 Mb and is organized into four circular parts, including one main chromosome and three smaller plasmids.
  • The main chromosome measures 6.72 Mb, while the plasmids are sized at 0.29 Mb, 0.17 Mb, and 0.07 Mb, respectively.
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Article Synopsis
  • The complete genome sequence of Burkholderia ambifaria strain Q53, an environmental rhizobacterium found in peanut plant roots, has been reported.
  • The genome is 7.4 million base pairs long and is organized into three circular chromosomes.
  • Researchers used a combination of long-read and short-read sequencing methods to determine the genome's structure.
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Bacterial surface components and extracellular compounds such as exopolysaccharides (EPSs) are crucial for interactions between cells, tolerance to different types of stress, and host colonization. Sinorhizobium meliloti produces two EPSs: Succinoglycan (EPS I), which is involved in the establishment of symbiosis with Medicago sativa, and galactoglucan (EPS II), associated with biofilm formation and the promotion of aggregation. Here, we aimed to assess their role in aggregative interactions between cells of the same strain of a given species (auto-aggregation), and between genetically different strains of the same or different species (intra- or intergeneric coaggregation).

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Article Synopsis
  • - The genome sequence of Mesorhizobium ciceri strain R30 has been fully reported, highlighting its significance as a commercial inoculant for chickpea in Argentina.
  • - The total genome size is nearly 7 megabases (Mb), structured in two circular components: a main chromosome measuring 6.49 Mb and a smaller plasmid of 0.46 Mb.
  • - This strain is important for enhancing chickpea growth, making it a valuable resource for agricultural practices in the region.
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Article Synopsis
  • The complete genome sequence of sp. strain C-145, a key nitrogen-fixing rhizobacterium for peanuts in Argentina, has been sequenced.
  • The genome is 9.53 million base pairs (Mbp) long and is organized in a single circular chromosome.
  • The sequencing was achieved using a combination of long- and short-read assembly techniques.
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is a soil bacterium of great agricultural importance because of its ability to fix atmospheric nitrogen in symbiotic association with alfalfa () roots. We looked into the involvement of exopolysaccharides (EPS) in its survival when exposed to different environmental stressors, as well as in bacteria-bacteria and bacteria-substrate interactions. The strains used were wild-type Rm8530 and two strains that are defective in the biosynthesis of EPS II: wild-type Rm1021, which has a non-functional locus, and mutant Rm8530 .

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Bacterial surface molecules have an important role in the rhizobia-legume symbiosis. Ensifer meliloti (previously, Sinorhizobium meliloti), a symbiotic Gram-negative rhizobacterium, produces two different exopolysaccharides (EPSs), termed EPS I (succinoglycan) and EPS II (galactoglucan), with different functions in the symbiotic process. Accordingly, we undertook a study comparing the potential differences in alfalfa nodulation by E.

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Bacterial surface molecules are crucial for the establishment of a successful rhizobia-legume symbiosis, and, in most bacteria, are also critical for adherence properties, surface colonization, and as a barrier for defense. Rhizobial mutants defective in the production of exopolysaccharides (EPSs), lipopolysaccharides (LPSs), or capsular polysaccharides are usually affected in symbiosis with their plant hosts. In the present study, we evaluated the role of the combined effects of LPS and EPS II in cell-to-cell and cell-to-surface interactions in Sinorhizobium meliloti by studying planktonic cell autoaggregation, biofilm formation, and symbiosis with the host plant Medicago sativa.

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Biochemistry courses in the Department of Molecular Biology at the National University of Río Cuarto, Argentina, are designed for undergraduate students in biology, microbiology, chemistry, agronomy, and veterinary medicine. Microbiology students typically have previous coursework in general, analytical, and organic chemistry. Programmed sequences of lab experiments allow these students to investigate biochemical problems whose solution is feasible within the context of their knowledge and experience.

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Biofilms are microbial communities that adhere to biotic or abiotic surfaces and are enclosed in a protective matrix of extracellular compounds. An important advantage of the biofilm lifestyle for soil bacteria (rhizobacteria) is protection against water deprivation (desiccation or osmotic effect). The rhizosphere is a crucial microhabitat for ecological, interactive, and agricultural production processes.

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Bacteria of the genus Bradyrhizobium are able to establish a symbiotic relationship with peanut (Arachis hypogaea) root cells and to fix atmospheric nitrogen by converting it to nitrogenous compounds. Quorum sensing (QS) is a cell-cell communication mechanism employed by a variety of bacterial species to coordinate behavior at a community level through regulation of gene expression. The QS process depends on bacterial production of various signaling molecules, among which the N-acylhomoserine lactones (AHLs) are most commonly used by Gram-negative bacteria.

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