FIG. 3.

Organization of the genes of the htx and phn operons involved in the metabolism of phosphonates in P. stutzeri compared to that of the phn operon of E. coli. The black arrow represents genes within the htx operon that are not homologous to any phn gene, green arrows represent genes likely involved in phosphonate transport, red arrows represent genes with putative regulatory function, blue arrows represent genes thought to encode the catalytic components of the C—P lyase, and gold arrows represent genes believed to encode accessory proteins to C—P lyase. The percentages of predicted amino acid sequence identity between each of the homologous proteins are indicated.