We used an integrative genetics approach using sequences of (1) nuclear ribosomal rDNA (internal transcribed spacers and partial large subunit rDNA), (2) single-copy microsatellite nuclear DNA, (3) chloroplast-encoded 23S rDNA, (4) mitochondrial cytochrome b, and (5) repeat variation at eight microsatellite markers, to test the hypothesis that the stress-tolerant, ‘morphologically cryptic’ Clad...

The set of "expansion segments" of any eukaryotic 26S/28S ribosomal RNA (rRNA) gene is responsible for the bulk of the difference in length between the prokaryotic 23S rRNA gene and the eukaryotic 26S/28S rRNA gene. The expansion segments are also responsible for interspecific fluctuations in length during eukaryotic evolution. They show a consistent bias in base composition in any species; for...

In addition to forming symbiotic nodules on legumes, rhizobial strains are members of soil or rhizosphere communities or occur as endophytes, e.g., in rice. Two rhizobial strains which have been isolated from root nodules of the aquatic legumes Aeschynomene fluminensis (IRBG271) and Sesbania aculeata (IRBG74) were previously found to promote rice growth. In addition to analyzing their phylogene...

The bacterium Acidovorax avenae causes disease in a wide range of economically important monocotyledonous and dicotyledonous plants, including corn, rice, watermelon, anthurium, and orchids. Genotypic and phenotypic relatedness among strains of phytopathogenic A. avenae subsp. avenae, A. avenae subsp. citrulli, A. avenae subsp. cattleyae and A. konjaci, as well as all other Acidovorax species, ...

Apple proliferation (AP), pear decline (PD) and European stone fruit yellows (ESFY) are among the most economically important plant diseases that are caused by phytoplasmas. Phylogenetic analyses revealed that the 16S rDNA sequences of strains of each of these pathogens were identical or nearly identical. Differences between the three phytoplasmas ranged from 1.0 to 1.5% of nucleotide positions...

It was recently demonstrated that peptide bond formation can occur using an Escherichia coli naked 23S ribosomal RNA without any of the ribosomal proteins. Here, the six domains of the 23S ribosomal RNA were individually synthesized and shown to be capable, when complexed together, of stimulating the reaction. Omission and addition experiments indicated that the activity could be reconstituted ...