Figure 2.

Correlation of the number of tandem repeats with size of alpha-like proteins from type V and VIII GBS strains. (A) Western blot of SDS extracts of clinical type V and VIII GBS strains with antiserum raised to purified alpha-like protein from strain JM9–130013 demonstrating protein size variation. (B) Structure of corresponding alpha-like protein genes. Except for the number of repeats in the tandem repeat region, all sequences were identical (>99%) to Alp3. The size of the tandem repeat region correlated with protein size for each strain. Generation of the laddering patterns on the Western blot is presumed to be a result of proteolysis at specific sites within each tandem repeat (10).