title: Pilus-dependent, double-stranded DNA bacteriophage for Caulobacter.
abstract: Caulobacter phage phi 6, previously reported to adsorb specifically to bacterial flagella, was shown here to attach to pili more frequently than to flagella. Phage phi 6 was shown to contain double-stranded DNA by circular dichroism spectroscopy and thermal denaturation accompanied by a hyperchromic shift at 260 nm. Morphologically, phage phi 6 fits group B2 (H.-W. Ackermann, in A. I. Laskin and H. A. Lechevalier, ed., Handbook of Microbiology, vol. 1, p. 638-643, 1973) with a long, noncontractile tail and an elongate head. Pilus-less mutants of the host Caulobacter vibrioides CV6 are phage phi 6 resistant, whereas flagellum-less mutants, which produce pili, are phage susceptible. Treatments of susceptible cells which remove or immobilize pili and flagella, e.g., blending or cyanide, inhibited phage phi 6 infection. Our evidence suggests that phage of phi 6 initiates infection in a manner similar to the pilus-specific phages for Pseudomonas described previously (D. E. Bradley, Virology 51:489-492, 1973; D. E. Bradley and T. L. Pitt, J. Gen. Virol. 24:1-15, 1974).
mesh_terms: D001419:Bacteria / Q000648:ultrastructure; D001435:Bacteriophages / Q000502:physiology* / Q000648:ultrastructure; D010861:Fimbriae, Bacterial / Q000502:physiology*; D005407:Flagella / Q000502:physiology; D011190:Potassium Cyanide / Q000494:pharmacology
chemical_list: D011190:Potassium Cyanide