Transduction of the nitrogen-fixation genes in Klebsiella pneumoniae.

The bacteriophage P1 infects and functions as a generalized transducing phage for nitrogen-fixing strains of the coliform bacterium Klebsiella pneumoniae. Bacterial mutants (nif(-)) unable to grow on molecular nitrogen as a nitrogen source were found to be deficient in nitrogenase activity as assayed by the conversion of acetylene to ethylene. These mutants regained normal nitrogenase activity and the ability to grow on N(2) after transduction with lysates of P1 phage prepared from wild-type bacteria. Transductional analysis with P1 revealed that several nif genes are located on the genetic linkage map of Klebsiella near the histidine operon.