Countercurrent distribution of poliovirus type 1

Abstract

Differences in the countercurrent distribution pattern in an aqueous polymer phase system are demonstrated for various strains of poliovirus type 1. The attenuated strains L Sc 2 ab and Baylor Att.-1 have partition coefficients of 0.2–0.4 whereas the CHAT strains and a virulent strain have partition coefficients of ≈4. Other strains tested were heterogeneous. The distribution pattern for homogeneous strains, which is genetically determined, is shown to be correlated to the m marker, since the strains with a low partition coefficient are m − and those with a high partition coefficient are m + . m + mutants from the m − strain L Sc 2 ab were shown to have a high partition co-efficient. The d character may also be correlated to the distribution pattern whereas other markers tested showed no evidence of correlation. The countercurrent fractionation can be used to eliminate m + mutants from virus pools.