The complete genome sequence of strain CCMM B554 (FSM-MA), a highly effective nitrogen-fixing microsymbiont of Gaertn.

Strain CCMM B554, also known as FSM-MA, is a soil dwelling and nodule forming, nitrogen-fixing bacterium isolated from the nodules of the legume L. in the Maamora Forest, Morocco. The strain forms effective nitrogen fixing nodules on species of the , and genera and is exceptional because it is a highly effective symbiotic partner of the two most widely used accessions, A17 and R108, of the model legume Gaertn.

Specific Host-Responsive Associations Between Medicago truncatula Accessions and Sinorhizobium Strains.

Legume plants interact with rhizobia to form nitrogen-fixing root nodules. Legume-rhizobium interactions are specific and only compatible rhizobia and plant species will lead to nodule formation. Even within compatible interactions, the genotype of both the plant and the bacterial symbiont will impact on the efficiency of nodule functioning and nitrogen-fixation activity.

Ploidy-dependent changes in the epigenome of symbiotic cells correlate with specific patterns of gene expression.

The formation of symbiotic nodule cells in is driven by successive endoreduplication cycles and transcriptional reprogramming in different temporal waves including the activation of more than 600 cysteine-rich genes expressed only in nodules. We show here that the transcriptional waves correlate with growing ploidy levels and have investigated how the epigenome changes during endoreduplication cycles. Differential DNA methylation was found in only a small subset of symbiotic nodule-specific genes, including more than half of the genes, whereas in most genes DNA methylation was unaffected by the ploidy levels and was independent of the genes' active or repressed state.

Extreme specificity of NCR gene expression in Medicago truncatula.

Background: Legumes form root nodules to house nitrogen fixing bacteria of the rhizobium family. The rhizobia are located intracellularly in the symbiotic nodule cells. In the legume Medicago truncatula these cells produce high amounts of Nodule-specific Cysteine-Rich (NCR) peptides which induce differentiation of the rhizobia into enlarged, polyploid and non-cultivable bacterial cells.

Complete genome sequence of Propionibacterium acnes type IB strain 6609.

Propionibacterium acnes is an anaerobic Gram-positive bacterium that forms part of the normal human cutaneous microbiota and is thought to play a central role in acne vulgaris, a chronic inflammatory disease of the pilosebaceous unit (I. Kurokawa et al., Exp.