Herbaspirillum seropedicae Z67 is a diazotrophic endophyte able to colonize the interior of many economically relevant crops such as rice, wheat, corn and sorghum. Structures siderophores produced by bacterial endophytes have not yet been elucidated. The aim this work was identify characterize bacterium. In screening for mutants unable produce we found mutant that had transposon insertion in non-ribosomal peptide synthase (NRPS) gene coding putative siderophore biosynthetic enzyme. chemical...

ABSTRACT Among the leguminous trees native to Uruguay, Parapiptadenia rigida (Angico), a Mimosoideae legume, is one of most promising species for agroforestry. Like many other legumes, it able establish symbiotic associations with rhizobia and belongs group known as nitrogen-fixing trees, which are major components agroforestry systems. Information about rhizobial symbionts this genus scarce, thus, aim work was identify characterize associated P. . A collection Angico-nodulating isolates...

The large legume genus Mimosa is known to be associated with both alphaproteobacterial and betaproteobacterial symbionts, depending on environment plant taxonomy, e.g., Brazilian species are preferentially nodulated by Burkholderia, whereas those in Mexico symbionts. Little known, however, about the symbiotic preferences of spp. at southern subtropical limits genus. In present study, rhizobia were isolated from field-collected nodules that native a region Uruguay. Phylogenetic analyses...

Abstract Background Microbes are present in almost every environment on Earth, even those with extreme environmental conditions such as Antarctica, where rocks may represent the main refuge for life. Lithobiontic communities composed of microorganisms capable colonizing and, it is a not so well studied bacterial community, they very interesting source diversity and functional traits potential biotechnological applications. In this work we analyzed ability Antarctic lithobiontic bacterium to...

ABSTRACT Fur is a transcriptional regulator involved in iron-dependent control of gene expression many bacteria. In this work we analyzed the phenotype fur mutant Sinorhizobium meliloti , an α-proteobacterium that fixes N 2 association with host plants. We demonstrated some functions high-affinity iron transport, siderophore production, and iron-regulated outer membrane protein respond to Fur-independent manner. However, manganese-dependent MntABCD manganese transport system was lost strain...

Many animal-pathogenic bacteria can use heme compounds as iron sources. Like these microorganisms, rhizobium strains interact with host organisms where are available. Results presented in this paper indicate that the of hemoglobin an source is not restricted to microorganisms. We also demonstrate heme, hemoglobin, and leghemoglobin act sources under iron-depleted conditions for Rhizobium meliloti 242. Analysis acquisition mutant indicates siderophore-, heme-, hemoglobin-,...

Cuban rice cultivars INCA LP-5 and LP-7 are widely distributed in Cuba Caribbean countries. Although there studies about rhizospheric bacteria associated with these cultivars, no reports their seed-associated bacteria. This study aimed to isolate endophytic from seeds select those the greatest plant growth-promoting traits. A total of nineteen bacterial strains genera Pantoea, Bacillus, Paenibacillus, Pseudomonas were isolated husk endosperm seeds. The Pantoea sp. S5-1, S5-38, S7-1...

A nodule-inhabiting

One major limitation of function-driven metagenomics is the ability host to express metagenomic DNA correctly. Differences in transcriptional, translational, and post-translational machinery between organism which belongs strain are all factors that influence success a functional screening. For this reason, use alternative hosts an appropriate approach favor identification enzymatic activities metagenomics. To be implemented, tools should designed build libraries those hosts. Moreover,...

ABSTRACT In Sinorhizobium meliloti , the Mur Sm protein, a homologue of ferric uptake regulator (Fur), mediates manganese-dependent regulation MntABCD manganese system. this study, we analyzed binding to promoter region S. mntA gene. We demonstrated that protein binds with high affinity gene in manganese-responsive manner. Moreover, results presented here indicate two monomers, or one dimer, DNA. The was identified by DNase I footprinting analysis and covers about 30 bp long contains...

The interior of plants contains microorganisms (referred to as endophytes) that are distinct from those present at the root surface or in surrounding soil. Herbaspirillum seropedicae strain SmR1, belonging betaproteobacteria, is an endophyte colonizes crops, including rice, maize, sugarcane, and sorghum. Different approaches have revealed genes pathways regulated during interactions H. with its plant hosts. However, functional genomic analysis transposon (Tn) mutants has been hampered by...

Sinorhizobium meliloti has multiple systems for iron acquisition, including the use of haem as an source. Haem internalization involves ShmR outer membrane receptor and hmuTUV locus, which participates in transport across cytoplasmic membrane. Previous studies have demonstrated that expression shmR gene is negatively regulated by through RirA. Here, we identify hmuP a genetic screen mutants displayed aberrant control . The normal induction response to limitation was lost mutant, showing this...

Two transposon-induced mutants of Sinorhizobium meliloti 242 were isolated based on their inability to grow rich medium supplemented with the metal chelator ethylenediamine di-o-hydroxyphenylacetic acid (EDDHA) and either heme-compounds or siderophores as iron sources. Tagged loci these identified sitB sitD genes. These genes encode components an ABC (ATP-binding cassette) metal-type permease in several Gram-negative bacteria. In this work, phenotypes two compared those siderophore-mediated...

Strain UY79T was isolated from a root nodule of Arachis villosa, collected at the Esteros de Farrapos National Park, Río Negro, Uruguay. Cells were non-motile Gram-variable rods with central to subterminal oval ellipsoidal endospores that swell sporangia. Growth observed in range 15-42 °C (optimum, 30 °C), pH 5.0-9.0 7.0-8.0) and up 3 % (w/v) NaCl 1-2 %). facultative anaerobic, catalase-positive oxidase-negative. According results 16S rRNA gene sequence analysis, belongs genus Paenibacillus...

ABSTRACT Rhizobia are soil bacteria that able to establish symbiotic associations with leguminous hosts. In iron-limited environments these can use iron present in heme or compounds (hemoglobin, leghemoglobin). Here we report the presence Sinorhizobium meliloti of an iron-regulated outer membrane protein is bind hemin but not hemoglobin. Protein assignment was done by matrix-assisted laser desorption ionization-time flight mass spectrometry. Tryptic peptides correlated measurements obtained...

It is estimated that more than three quarters of the Earth’s biosphere in perennially cold environments. Despitethe extreme environmental conditions desiccation and freezing, microbes can colonize these habitats through adaptationof metabolic functions synthesis structurally adapted enzymes. Enzymes within psychrophilic exhibit highspecific activity at low moderate temperature, with thermostability. In this study we used a classic microbiologicalapproach to isolate Antarctic bacteria...

Herbaspirillum seropedicae Z67 is a diazotrophic endophyte able to colonize the interior of many economically relevant crops such as rice, wheat, corn and sorghum. Under iron-deficient conditions, this organism secretes serobactins, suite lipopetide siderophores. The role siderophores in interaction between endophytes their plant hosts are not well understood. In work, we aimed determine importance serobactins-mediated iron acquisition systems H. with rice plants. First provide evidence, by...

Herbaspirillum seropedicae Z67 is a nitrogen-fixing endophyte that colonizes many important crops. Like in almost all organisms, vital cellular processes of this are iron dependent. In order to efficiently acquire fulfill its requirements, bacterium produces the siderophores serobactins. However, presence genome others acquisition genes suggests serobactins not only strategy used by H. circumvent metal deficiency. The aim work was identify and proteins differentially expressed cells growing...

A metagenomic fosmid library from bovine rumen was used to identify clones with lipolytic activity. One positive clone isolated. The gene responsible for the observed phenotype identified by in vitro transposon mutagenesis and sequencing named est10. 367 amino acids sequence harbors a signal peptide, conserved secondary structure arrangement of alpha/beta hydrolases, GHSQG pentapeptide which is characteristic esterases lipases. Homology based 3D-modelling confirmed spatial orientation serine...