Publications by authors named "Jean Franco Castro"

Chile leads cherry exports in the southern hemisphere with a total of 415.315 t exported in the 2022 to 2023 season (IQonsulting, 2023). canker, produced by spp.

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Stem blight is a destructive woody disease of blueberry () caused by several species of the family Botryosphaeriaceae. A field survey was conducted in the mayor blueberry production area of Chile, comprising latitudes 32°49'S to 40°55'S, to determine the occurrence and distribution of Botryosphaeriaceae in the region. Together, a multilocus analysis, morphological characterization, and phytopathogenicity testing were used to identify 51 isolates belonging to (28 strains), (22 strains), and (1 strain).

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Bacteria belonging to the phylum are a very good source of antibiotics, and indeed dominate the current clinical antibiotic space. This paper reports Mutactimycin AP, a new compound belonging to an anthracycline-type family of antibiotics, isolated from a This actinobacterial strain was isolated from the rhizosphere of lupine plants growing in the extreme hyper-arid Atacama Desert. Structural characterization was carried out using electrospray ionization-mass spectrometry (ESI-MS) and NMR spectroscopy in combination with molecular modelling.

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Vaccinium corymbosum L. is the most cultivated blueberry species in Chile. Chilean fruits typically take up to 50 days to reach oversea markets; therefore, controlling post-harvest pathogens is of outmost importance to maintain international food safety and quality standards.

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The RGM 2450 and RGM 2529 strains were isolated from the rhizosphere of plants presenting resilience to abiotic and biotic stress conditions. To understand the implications of bacteria in resilience, a genomic and experimental analysis was carried out on their biostimulant and phytopathogenic antagonist properties. Genome analyses of both strains indicated that they have the potential to synthesize bioactive compounds such as the battery of non-ribosomal peptides, polyketides, extracellular enzymes and phytohormones.

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The entomopathogenic fungus strain RGM 2184 can reach a maximum efficacy of 80% against the quarantine pest in field assays. In this study, the RGM 2184 genome was sequenced, and genome mining analyses were performed to predict the factors involved in its insecticidal activity. Additionally, the metabolic profiling of the RMG 2184 culture's supernatants was analyzed by mass spectrometry, and the insecticidal activity from one of these extracts was evaluated in larvae.

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Lasso peptides are a diverse class of ribosomally synthesized and post-translationally modified peptides (RiPPs). Their proteolytic and thermal stability alongside their growing potential as therapeutics has increased attention to these antimicrobial peptides. With the advent of genome mining, the discovery of RiPPs allows for the accurate prediction of putatively encoded structures, however, MS experiments only provide partial sequence confirmation, therefore 2D NMR experiments are necessary for characterisation.

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causes substantial losses in tomato and chili pepper crops worldwide. Endophytes have shown the potential for the biological control of diseases. The colonization ability of native endophyte strains of and their antifungal effect against were evaluated in crops.

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Analysis of the genome sequence of C34 identified biosynthetic gene clusters (BGCs) for three different lasso peptides (Lp1, Lp2, and Lp3) which were not known to be made by the strain. Lasso peptides represent relatively new members of the RiPP (ribosomally synthesized and posttranslationally modified peptides) family of natural products and have not been extensively studied. Lp3, whose production could be detected in culture supernatants from C34 and after heterologous expression of its BGC in , is identical to the previously characterized chaxapeptin.

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A set of oligonucleotide primers, Rubro223f and Rubro454r, were found to amplify a 267 nucleotide sequence of 16S rRNA genes of Rubrobacter type strains. The primers distinguished members of this genus from other deeply-rooted actinobacterial lineages corresponding to the genera Conexibacter, Gaiella, Parviterribacter, Patulibacter, Solirubrobacter and Thermoleophilum of the class Thermoleophilia. Amplification of DNA bands of about 267 nucleotides were generated from environmental DNA extracted from soil samples taken from two locations in the Atacama Desert.

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This study was designed to determine the plant growth promoting (PGP) potential of members of the genus . To this end, the genomes of 21 representative strains were examined for genes associated directly or indirectly with plant growth. All of the genomes contained genes that encoded for products associated with the biosynthesis of auxins [indole-3-glycerol phosphate synthases, anthranilate phosphoribosyltransferases (D), anthranilate synthases, and aminases (A and B)], cytokinins (11 well-conserved genes within the predicted biosynthetic gene cluster), siderophores, and nitrogenases ( operon except for atypical ) as well as genes that modulate the effects of biotic and abiotic environmental stress (e.

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A Gram-reaction-positive, aerobic bacterial strain showing coccoid cells and designated as BC 501 was isolated from a black patina of the surface of a Carrara marble blockin the Gioia quarry in Tuscany, Italy. A polyphasic study was carried out to clarify the taxonomic status of BC 501 within the evolutionary radiation of the genus Modestobacter. Phenotypic and genotypic characteristics as well as phylogenetic distinctiveness confirmed that it represents a novel species of the genus Modestobacter, for which the name Modestobacteritalicus sp.

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The taxonomic status, biotechnological and ecological potential of several Micromonospora strains isolated from an extreme hyper arid Atacama Desert soil were determined. Initially, a polyphasic study was undertaken to clarify the taxonomic status of five micromonosporae, strains LB4, LB19, LB32, LB39 and LB41, isolated from an extreme hyper-arid soil collected from one of the driest regions of the Atacama Desert. All of the isolates were found to have chemotaxonomic, cultural and morphological properties consistent with their classification in the genus Micromonospora.

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A polyphasic study was undertaken to establish the taxonomic status of a Blastococcus strain isolated from an extreme hyper-arid Atacama Desert soil. The isolate, strain P6, was found to have chemotaxonomic and morphological properties consistent with its classification in the genus Blastococcus. It was shown to form a well-supported branch in the Blastococcus 16S rRNA gene tree together with the type strains of Blastococcus capsensis and Blastococcus saxobsidens and was distinguished from the latter, its close phylogenetic neighbour, by a broad range of phenotypic properties.

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A polyphasic study was undertaken to establish the taxonomic status of three representative Geodermatophilus strains isolated from an extreme hyper-arid Atacama Desert soil. The strains, isolates B12, B20 and B25, were found to have chemotaxonomic and morphological properties characteristic of the genus Geodermatophilus. The isolates shared a broad range of chemotaxonomic, cultural and physiological features, formed a well-supported branch in the Geodermatophilus 16S rRNA gene tree in which they were most closely associated with the type strain of Geodermatophilus obscurus.

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The taxonomic position of a novel Amycolatopsis strain isolated from a high altitude Atacama Desert subsurface soil was established using a polyphasic approach. The strain, isolate H5, was shown to have chemical properties typical of members of the genus Amycolatopsis such as meso-diaminopimelic acid as the diamino acid in the cell wall peptidoglycan, arabinose and galactose as diagnostic sugars and MK-9(H) as the predominant isoprenologue. It also has cultural and morphological properties consistent with its classification in the genus, notably the formation of branching substrate hyphae which fragment into rod-like elements.

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Streptomyces leeuwenhoekii strains C34, C38, C58 and C79 were isolated from a soil sample collected from the Chaxa Lagoon, located in the Salar de Atacama in northern Chile. These streptomycetes produce a variety of new specialised metabolites with antibiotic, anti-cancer and anti-inflammatory activities. Moreover, genome mining performed on two of these strains has revealed the presence of biosynthetic gene clusters with the potential to produce new specialised metabolites.

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Metabolic modelling is a useful tool that enables the rational design of metabolic engineering experiments and the study of the unique capabilities of biotechnologically important microorganisms. The extreme abiotic conditions of the Atacama Desert have selected microbial diversity with exceptional characteristics that can be applied in the mining industry for bioleaching processes and for production of specialised metabolites with antimicrobial, antifungal, antiviral, antitumoral, among other activities. In this review we summarise the scientific data available of the use of metabolic modelling and flux analysis to improve the performance of Atacama Desert microorganisms in biotechnological applications.

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A polyphasic study was undertaken to determine the taxonomic status of a Streptomyces strain which had been isolated from a high altitude Atacama Desert soil and shown to have bioactive properties. The strain, isolate H9, was found to have chemotaxonomic, cultural and morphological properties that place it in the genus Streptomyces. 16S rRNA gene sequence analyses showed that the isolate forms a distinct branch at the periphery of a well-delineated subclade in the Streptomyces 16S rRNA gene tree together with the type strains of Streptomyces crystallinus, Streptomyces melanogenes and Streptomyces noboritoensis.

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Background: Next Generation DNA Sequencing (NGS) and genome mining of actinomycetes and other microorganisms is currently one of the most promising strategies for the discovery of novel bioactive natural products, potentially revealing novel chemistry and enzymology involved in their biosynthesis. This approach also allows rapid insights into the biosynthetic potential of microorganisms isolated from unexploited habitats and ecosystems, which in many cases may prove difficult to culture and manipulate in the laboratory. Streptomyces leeuwenhoekii (formerly Streptomyces sp.

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Streptomyces leeuwenhoekii, isolated from the hyperarid Atacama Desert, produces the new ansamycin-like compounds chaxamycins A to D, which possess potent antibacterial activity and moderate antiproliferative activity. We report the development of genetic tools to manipulate S. leeuwenhoekii and the identification and partial characterization of the 80.

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