Functional organization of the kdp genes of Escherichia coli K-12

D. B. Rhoads, L. Laimins, W. Epstein

Research output: Contribution to journalArticlepeer-review

41 Scopus citations


The kdp genes code for a high-affinity and repressible K+ transport system. The regulation and organization of the kdp genes were analyzed by studies of constitutive mutants and of strains in which bacteriophage λ is integrated into the kdp genes. The polar effects of λ integration demonstrate that three of the kdp genes form an operon, kdpABC, read from A to C. The kdpD gene is a separate transcription unit and is the site of mutations making expression of the kdp genes partially constitutive. The constitutive mutants are dominant to kdpD+ in diploids. These findings, the fact that kdpD mutations identified previously are Kdp-, and the existence of intracistronic complementation between some kdpD mutations indicate that the kdpD gene product is an oligomeric positive regulator of the kdp genes. Deletions extending clockwise from kdp as far as the gltA locus were isolated from strains with bacteriophage λ integrated into kdpD. Plaqueforming transducing λ phages carrying the kdpABC operon were isolated.

Original languageEnglish (US)
Pages (from-to)445-452
Number of pages8
JournalJournal of bacteriology
Issue number2
StatePublished - 1978

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology


Dive into the research topics of 'Functional organization of the kdp genes of Escherichia coli K-12'. Together they form a unique fingerprint.

Cite this