Table 1.

Purification profile of RNase P from HeLa whole cell extracts

Step	Volume, ml	Total protein, mg	Total activity, units × 105	Specific activity, units/mg × 105	Purification, -fold
S100	450	6300	9,000	1.4	—
DEAE	180	740	32,000	43	31
Glycerol	81	140	24,000	170	121
Mono Q	7.2	2.9	2,100	720	510
S-12	2.0	0.2	640	3200	2300

One unit is defined as the amount of enzyme required to convert 1 μmol of substrate to product in 1 min at 37°C