From OMPwiki
Jump to: navigation, search

White, BJ, Hochhauser, SJ, Cintron, NM and Weiss, B (1976) Genetic mapping of xthA, the structural gene for exonuclease III in Escherichia coli K-12.J. Bacteriol. 126:1082-8


The genes xthA, pncA, and pabB were ordered relative to others by two- and three-factor transductional crosses with bacteriophage P1. The genes studied span 2 min (2%) of the genetic map of Escherichia coli K-12 in the clockwise sequence pheS-pfkB-xthA-pncA-gap-pabB-fadD. Eleven independently derived xth mutations were examined; all were known to affect exonuclease III and its associated endonuclease II activity, and all were mapped in the xthA region. pncA mutations were found to confer resistance to 6-aminonicotinamide, whereas some pheS mutations are known to specify resistance to p-fluorphenylalanine. xth mutations were readily transferred into other strains by selecting for these co-transducible drug resistance markers.




6-Aminonicotinamide; Chromosome Mapping; Deoxyribonucleases; Drug Resistance, Microbial; Endonucleases; Escherichia coli; Exonucleases; Genes; Transduction, Genetic; p-Fluorophenylalanine

Main Points of the Paper

Please summarize the main points of the paper.

Materials and Methods Used

Please list the materials and methods used in this paper (strains, plasmids, antibodies, etc).

Phenotype Annotations

See Help:AnnotationTable for details on how to edit this table.

Phenotype of Taxon Information Genotype Information (if known) Condition Information OMP ID OMP Term Name ECO ID ECO Term Name Notes Status

a mutation or genetic difference within a strain

  • Taxon: Escherichia coli
  • Strain: K-12
  • Substrain:
  • NCBI Taxon ID: 83333
  • Genotype of Reference Strain: pncA
  • Genotype of Experimental Strain : pncA
  • Reference Condition:

increased resistance to antibiotics


non-traceable author statement

Resistant to 6-amino-nicotinamide



See Help:References for how to manage references in OMPwiki.