Rhizobiales (Alphaproteobacteria) are well-known beneficial partners in plant-microbe interactions. Less is known about the occurrence and function of Rhizobiales in the lichen symbiosis, although it has previously been shown that Alphaproteobacteria are the dominating group in growing lichen thalli. We have analyzed the taxonomic structure and assigned functions to Rhizobiales within a metagen...

The genetic characterization of a 5.5-kb chromosomal region of Sinorhizobium meliloti 2011 that contains lpsB, a gene required for the normal development of symbiosis with Medicago spp., is presented. The nucleotide sequence of this DNA fragment revealed the presence of six genes: greA and lpsB, transcribed in the forward direction; and lpsE, lpsD, lpsC, and lrp, transcribed in the reverse dire...

The Brucella BvrR/BvrS two-component regulatory system is homologous to the ChvI/ChvG systems of Sinorhizobium meliloti and Agrobacterium tumefaciens necessary for endosymbiosis and pathogenicity in plants. BvrR/BvrS controls cell invasion and intracellular survival. Probing the surface of bvrR and bvrS transposon mutants with monoclonal antibodies showed all described major outer membrane prot...

Evaluation of the soil rhizosphere has been limited by the lack of robust assessments that can explore the vast complex structure and diversity of soil microbial communities. Our objective was to combine fatty acid methyl ester (FAME) and pyrosequencing techniques to evaluate soil microbial community structure and diversity. In addition, we evaluated biogeochemical functionality of the microbia...

Higher plants contain potentially vast sources of nutrients for the myriad bacterial species in their environment, and most bacteria are small enough to pass through stomates and other natural openingsinto the apoplast-the anteroom for these riches. However, surprisingly few bacteria raid the nutrient stores of living plant cells, apparently because the metabolic intimacy involved in parasitism...

The establishment of a nitrogen-fixing symbiosis is an economically important plant phenomenon. Biological reduction of dinitrogen to ammonia is among the most effective fixation systems facilitating the plant growth in nitrogen starved soils without the requirement of massive inputs of fertilizers. This process occurs in legumes roots in structures called nodules. Nodule development is induced...

The Pacific coast tick, Dermacentor occidentalis Marx, is found throughout California and can harbor agents that cause human diseases such as anaplasmosis, ehrlichiosis, tularemia, Rocky Mountain spotted fever and rickettsiosis 364D. Previous studies have demonstrated that nonpathogenic endosymbiotic bacteria can interfere with Rickettsia co-infections in other tick species. We hypothesized tha...

BACKGROUND Porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric pathogen of swine. The spike glycoprotein (S) of PEDV is the major immunogenic determinant that plays a pivotal role in the induction of neutralizing antibodies against PEDV, which therefore is an ideal target for the development of subunit vaccine. In an attempt to develop a subunit vaccine for PEDV, we cloned two...

Nitrogen is the nutrient plants require in the highest amount, and in agriculture nitrogen availability has a major influence on both yield and product quality. In nature plants acquire nitrogen by assimilation of nitrate and ammonium or from dinitrogen through association with nitrogen-fixing bacteria. Symbiotic nitrogen fixation, where the plant supplies the carbon source for the energy-depen...