Influencing factors of purifications treatments on cell counts determined by Coulter Counter. (A) Cell counts for E. coli cultures before (black bars) and after (gray bars) purification procedures. Denomination of procedures is according to Table 1. Error bars resulted from nine different measurements. (B) Influence of filtration: Cell counts of E. coli purified with procedure 1-C2-S2-H1-F2 prior to vacuum filtration with a 12–15 μm filter (black bar), after filtration (grey bar), and cell counts of residues on the filter (white bar). Error bars resulted from three different measurements.