TABLE 3.

Accumulation of osmoprotectants by salt-stressed E. coli MC4100^a

NaCl concn in M63 medium (M)	Amt of osmoprotectant accumulated (nmol mg of protein−1)
	DMSA	DMSP	GB
0	65	85	40
0.3	390	435	250
0.6	575	580	525
0.8	685	700	630

^aCultures were grown to the mid-exponential phase in M63 medium supplemented with NaCl. The steady-state levels of accumulated osmoprotectants were measured after dense cell suspensions (OD₅₇₀, 1) were incubated in the presence of [¹⁴C]GB, [¹⁴C]DMSA, or [¹⁴C]DMSP at a concentration of 1 mM (about 100,000 dpm in 200 μl).