Journal of Molecular Evolution

, Volume 48, Issue 2, pp 142–150

Physical and Genetic Map of the Genome of Buchnera, the Primary Endosymbiont of the Pea Aphid Acyrthosiphon pisum

Authors

  • Hubert  Charles
    • Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, Tokyo 113-0033, Japan
  • Hajime  Ishikawa
    • Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, Tokyo 113-0033, Japan
Article

DOI: 10.1007/PL00006452

Cite this article as:
Charles, H. & Ishikawa, H. J Mol Evol (1999) 48: 142. doi:10.1007/PL00006452

Abstract.

Abstract The genome of Buchnera, an endosymbiotic bacterium of the pea aphid Acyrthosiphon pisum, was characterized by pulse-field gel electrophoresis (PFGE) as a circular DNA molecule of 657 kb. The enzymes I-CeuI, CpoI, ApaI, SmaI, NaeI, SacII, MluI, FspI, and NruI were used to cleave the DNA of Buchnera into fragments of suitable size for PFGE analysis. A physical map of the Buchnera genome, including restriction fragments from seven of these enzymes, was constructed using double cutting, partial digestion, and hybridization with linking fragments, and 29 genes and operons were localized on the map. In addition, the genomic map of Buchnera was compared with those of Escherichia coli and Haemophilus influenzae. The gene order in Buchnera is more similar to that of E. coli than to H. influenzae. The dramatic shrinkage of the Buchnera genome compared with those of other members of the closely related Enterobacteriaceae family is discussed in terms of evolution under the influence of the intracellular symbiotic association.

Key words:Buchnera—Acyrthosiphon pisum— Pea aphid — Pulse-field gel electrophoresis — Genome size — Genetic map — Symbiosis

Copyright information

© Springer-Verlag New York Inc. 1999