TABLE 2.

Purification of B. subtilis recombinant CDA^a

Purification step	Total amt of protein (mg)	Total activity (U)b	Sp act (U/mg)	Yield (%)
1. Crude extract	331	8,280	25	100
2. Streptomycin	293	9,080	31	110
3. DEAE	79	5,280	67	57
4. Heat treatment	31	4,590	149	55
5. G-100 filtration	25	3,690	148	44
6. Q5 FPLC	7	1,250	176	15

^aFrom 1 liter of bacterial culture. 

^bUnits are micromoles of cytidine deaminated per minute at 25°C.