The 160-Kilobase Genome of the Bacterial Endosymbiont Carsonella

  title={The 160-Kilobase Genome of the Bacterial Endosymbiont Carsonella},
  author={Atsushi Nakabachi and Atsushi Yamashita and Hidehiro Toh and Hajime Ishikawa and Helen E Dunbar and Nancy A. Moran and Masahira Hattori},
  pages={267 - 267}
Previous studies have suggested that the minimal cellular genome could be as small as 400 kilobases. Here, we report the complete genome sequence of the psyllid symbiont Carsonella ruddii, which consists of a circular chromosome of 159,662 base pairs, averaging 16.5% GC content. It is by far the smallest and most AT-rich bacterial genome yet characterized. The genome has a high coding density (97%) with many overlapping genes and reduced gene length. Genes for translation and amino acid… 
Loss of Conserved Noncoding RNAs in Genomes of Bacterial Endosymbionts
It is found that the loss of cis-regulatory ncRNA sequences, which regulate the expression of cognate protein-coding genes, is characterized by the reduction of secondary structure formation propensity, GC content, and length of the corresponding genomic regions.
The bacterial essence of tiny symbiont genomes.
Genome size of Pachypsylla venusta (Hemiptera: Psyllidae) and the ploidy of its bacteriocyte, the symbiotic host cell that harbors intracellular mutualistic bacteria with the smallest cellular genome
Psyllids harbor the primary symbiont, Carsonella ruddii (γ-Proteobacteria), within the cytoplasm of specialized cells called bacteriocytes, and whole genome analysis of psyllids provides a foundation for genomics-based research into host-symbiont interactions.
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Since 2006, numerous cases of bacterial symbionts with extraordinarily small genomes have been reported, pointing to highly degenerate genomes that retain only the most essential functions, often including a considerable fraction of genes that serve the hosts.
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Promoter Characterization in the AT-Rich Genome of the Obligate Endosymbiont “Candidatus Blochmannia floridanus”
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The genome of “Candidatus Carsonella ruddii” strain BT from Bactericera trigonica in Israel was sequenced and has a G+C content of 14.6%, with 224 predicted open reading frames (ORFs) and 30 RNAs.
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Instances of gene duplication, gene loss and gene acquisition through lateral transfer show that the three Frankia genomes are dynamic and have evolved as a function of their host characteristics and biogeography.
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Biology bacteriocyte-associated endosymbionts of plant sap-sucking insects.
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    Annual review of microbiology
  • 2005
Psyllids, whiteflies, aphids, and mealybugs are members of the suborder Sternorrhyncha and share a common property, namely the utilization of plant sap as their food source, and the different properties of the genomes and fragments of the genome suggest that there are different constraints on the permissible evolutionary changes.
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CORRECTIONS &CLARIFICATIONS Brevia: “The 160-kilobase genome of the bacterial endosymbiont Carsonella
  • 2006
CORRECTIONS &CLARIFICATIONS Brevia: “The 160-kilobase genome of the bacterial endosymbiont Carsonella,
  • 2006