Table 2.

Infectivity of purified r-coresa

Particle typePrepnbP/PFUcRelative P/PFUd
CoreA1.1 × 109 1.0
B5.0 × 108 1.0
r-coreA-12.1 × 106 530
A-22.3 × 106 480
B-11.4 × 106 360
B-2e 1.1 × 106 450
r-core(μ1-581D)B-11.9 × 106 260
Virion11507.3 × 106
21109.7 × 106
  • a See text for descriptions of r-cores.

  • b Each core preparation is designated with a capital letter. Each r-core preparation is designated with a letter, representing the core preparation from which it was derived, followed by the preparation number.

  • c Particle (P) per PFU values for each preparation were obtained by dividing P per milliliter by PFU per milliliter and are presented as an average of three determinations (SD < 0.10 log10 unit for all values). Concentrations of virion and core preparations were estimated by A260 (13, 51). Concentrations of r-core preparations were determined by densitometry of Coomassie blue-stained SDS-polyacrylamide gels compared with virion standards. Viral infectivity was measured by plaque assay (18).

  • d Defined as the ratio of P/PFU value of a preparation of cores to P/PFU value of a matching core or r-core preparation. Relative P/PFU values of virion preparations were calculated by using the PFU-per-milliliter value of core preparation A.

  • e Same as r-core preparation 2 in Fig. 1B and Table 1.