Rhizobial Secretion of Truncated Exopolysaccharides Severely Impairs the Symbiosis.

The symbiosis between R7A and Gifu is an important model system for investigating the role of bacterial exopolysaccharides (EPS) in plant-microbe interactions. Previously, we showed that R7A mutants that are affected at an early stage of EPS synthesis and in lipopolysaccharide (LPS) synthesis induce effective nodules on Gifu after a delay, whereas mutants affected in the biosynthesis of the EPS side chain induce small uninfected nodule primordia and are impaired in infection. The presence of a halo around the mutant when grown on Calcofluor-containing media suggested the mutant secreted a truncated version of R7A EPS.

A simple and efficient protocol for generating transgenic hairy roots using Agrobacterium rhizogenes.

For decades, Agrobacterium rhizogenes (now Rhizobium rhizogenes), the causative agent of hairy root disease, has been harnessed as an interkingdom DNA delivery tool for generating transgenic hairy roots on a wide variety of plants. One of the strategies involves the construction of transconjugant R. rhizogenes by transferring gene(s) of interest into previously constructed R.

Aromatic amino acid biosynthesis impacts root hair development and symbiotic associations in Lotus japonicus.

Legume roots can be symbiotically colonized by arbuscular mycorrhizal (AM) fungi and nitrogen-fixing bacteria. In Lotus japonicus, the latter occurs intracellularly by the cognate rhizobial partner Mesorhizobium loti or intercellularly with the Agrobacterium pusense strain IRBG74. Although these symbiotic programs show distinctive cellular and transcriptome signatures, some molecular components are shared.

A Promiscuity Locus Confers Nodulation with Rhizobia from Five Different Genera.

Legumes acquire access to atmospheric nitrogen through nitrogen fixation by rhizobia in root nodules. Rhizobia are soil-dwelling bacteria and there is a tremendous diversity of rhizobial species in different habitats. From the legume perspective, host range is a compromise between the ability to colonize new habitats, in which the preferred symbiotic partner may be absent, and guarding against infection by suboptimal nitrogen fixers.

Surface hydrophobics mediate functional dimerization of CYP121A1 of Mycobacterium tuberculosis.

Tuberculosis is caused by the pathogenic bacterium Mycobacterium tuberculosis (Mtb) and remains the leading cause of death by infection world-wide. The Mtb genome encodes a disproportionate number of twenty cytochrome P450 enzymes, of which the essential enzyme cytochrome P450 121A1 (CYP121A1) remains a target of drug design efforts. CYP121A1 mediates a phenol coupling reaction of the tyrosine dipeptide cyclo-L-Tyr-L-Tyr (cYY).

Functional genomics reveals the toxin-antitoxin repertoire and AbiE activity in .

Bacteriophage defences are divided into innate and adaptive systems. sp. ATCC 39006 has three CRISPR-Cas adaptive immune systems, but its innate immune repertoire is unknown.

Complete Genome Sequences of spp. Inoculant Strains sv. TA1 and CC275e: Resources for Genomic Study of the - Symbiosis.

symbiovar strains TA1 and CC275e are nitrogen-fixing microsymbionts of spp. and have been used as commercial inoculant strains for clovers in pastoral agriculture in Australia and New Zealand. Here we present the complete genome sequences of both strains, resolving their multipartite genome structures and allowing for future studies using genomic approaches.

Rhizobium leguminosarum bv. trifolii NodD2 Enhances Competitive Nodule Colonization in the Clover-Rhizobium Symbiosis.

Establishment of the symbiotic relationship that develops between rhizobia and their legume hosts is contingent upon an interkingdom signal exchange. In response to host legume flavonoids, NodD proteins from compatible rhizobia activate expression of nodulation genes that produce lipochitin oligosaccharide signaling molecules known as Nod factors. Root nodule formation commences upon legume recognition of compatible Nod factor.

Timing of indicated delivery after antenatal steroids in preterm pregnancies with severe hypertension.

Objectives: To evaluate the effect of the time interval between administering antenatal steroids needed to accelerate fetal lung maturity and indicated delivery in preterm pregnancies complicated by severe hypertension, as determined by maternal and perinatal outcomes.

Methods: The Nova Scotia Atlee Perinatal Database was used to identify a population-based cohort of women with severe hypertension who delivered an infant between 1989 and 2002. Women were included if they received antenatal steroids and required delivery between 26 and 34 weeks gestation.