. 2003 Aug;23(15):5217–5224. doi: 10.1128/MCB.23.15.5217-5224.2003

TABLE 1.

Enrichment of RIC during purification

Fraction	Protein (mg/ml)	Activity (U/ml)^a	Total activity (U)	Specific activity (U/mg)^b	Purifi- cation (fold)^c	Yield (%)^d
Inner membrane extract	1.2	73	58.4	60	—^e	100
Affinity 1 M K⁺ fraction	0.21	510	51	2,380	40	87
Glycerol gradient peak fraction	0.19	700	28	3,684	61	48

One unit of activity corresponds to the binding of 1 fmol of tRNA^Tyr in the electrophoretic mobility shift assay (Fig. 1).

Specific activity is expressed in terms of units per milligram of protein.

Increase in specific activity over the crude inner membrane extract.

Yield is the percentage of the total activity in the crude extract recovered in each fraction.

—, not applicable.