title: Short interrupted palindromes on the extragenic DNA of Escherichia coli K-12, Haemophilus influenzae and Neisseria meningitidis.
abstract: BACKGROUND
  The importance of the various kinds of repetitive nucleotide sequences for the workings of bacterial DNA has been widely recognized. This work is concerned with the distribution of a particular group of repetitive sequences, the short-sequenced interrupted extragenic palindromes, on the genetic maps of Escherichia coli K-12, Haemophilus influenzae Rd and Neisseria meningitidis Z2491 and MC58. A tool has been developed based upon a statistical hypothesis test taking into account the markovian structure of random sequences in order to determine the non-random character of extragenic palindromes.
  
  
  RESULTS
  Totals of 7631, 12904, 4722 and 5477 non-random short interrupted palindromes have been found on the E.coli, H.influenzae, and N.meningitidis serogroup A and serogroup B genomes, respectively. Their distribution patterns on the respective genomes vary according to the bacterial species considered. Based on their position on the genome, palindromes could be distinguished as those which integrate longer, repetitive sequences; those which stand in isolation, and still others are associated to specific genome sites.
  
  
  BACKGROUND
  The complete list of the observed palindromes is available at the site http://www/lncc.br/~atrv.
  
  
  BACKGROUND
  atrv@lncc.br
authors.affiliation: Laboratório Nacional de Computação Científica, MCT, Petrópolis, RJ, 25651-070, Brazil. atrv@lncc.br
authors.forename: A T
authors.initials: AT
authors.lastname: Vasconcelos
authors.forename: M A
authors.initials: MA
authors.lastname: Maia
authors.forename: D F
authors.initials: DF
authors.lastname: de Almeida
mesh_terms: D019295:Computational Biology; D004269:DNA, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005821:Genetic Techniques; D016680:Genome, Bacterial; D006193:Haemophilus influenzae / Q000235:genetics*; D009345:Neisseria meningitidis / Q000235:genetics*; D012044:Regression Analysis; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004269:DNA, Bacterial