Ribonucleotide reductase genes of Bacillus prophages: a refuge to introns and intein coding sequences.
The ribonucleotide reductase gene tandem bnrdE/bnrdF in SPbeta-related prophages of different Bacillus spp. isolates presents different configurations of intervening sequences, comprising one to three of six non-homologous splicing elements. Insertion sites of group I introns and intein DNA are clustered in three relatively short segments encoding functionally important domains of the ribonucleotide reductase. Comparison of the bnrdE homologs reveals mutual exclusion of a group I intron and an intein coding sequence flanking the codon that specifies a conserved cysteine. In vivo splicing was demonstrated for all introns. However, for two of them a part of the mRNA precursor molecules remains unspliced. Intergenic bnrdE-bnrdF regions are unexpectedly long, comprising between 238 and 541 nt. The longest encodes a putative polypeptide related to HNH homing endonucleases.
Lazarevic
V
V
Institut de Génétique et de Biologie Microbiennes, Rue César-Roux 19, CH-1005 Lausanne, Switzerland. vladimir.lazarevic@igbm.unil.ch
D001407:Bacillus / Q000235:genetics* / Q000821:virology*; D001435:Bacteriophages / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D017124:Conserved Sequence / Q000235:genetics; D003545:Cysteine / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D021901:DNA, Intergenic / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D005814:Genes, Viral / Q000235:genetics; D007438:Introns / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames / Q000235:genetics; D011533:Proviruses / Q000201:enzymology / Q000235:genetics*; D012313:RNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012264:Ribonucleotide Reductases / Q000235:genetics*
D004269:DNA, Bacterial; D021901:DNA, Intergenic; D004279:DNA, Viral; D012313:RNA; D012264:Ribonucleotide Reductases; D003545:Cysteine