TABLE 1.

Growth rates and proline, betaine, and total amino acid contents of wild-type and OSM35 cells grown under various conditions^a

Growth condition	μ (h−1)		Proline concn (nmol/mg of protein)		Betaine concn (nmol/mg of protein)		Amino acid concnb (nmol/mg of protein)
	wt	OSM35	wt	OSM35	wt	OSM35	wt	OSM35
CDM	0.61	0.59	10	12	–c	–	460	490
CDM + NaCl	0.43	0.51	4	5	–	–	560	790
CDM + Pro	0.75	0.76	15	25	–	–	370	470
CDM + Pro + NaCl	0.62	0.59	201	17	–	–	750	680
CDM + NaCl + Bet	0.61	0.51	5	6	530	–	520	730
CDM + Pro + NaCl + Bet	0.70	0.54	16	15	560	–	510	660

^aThe cells were cultivated in the indicated medium. The final concentrations of the various additives were as follows: proline, 5.9 mM; NaCl, 0.3 M; betaine, 1 mM. A volume of culture in exponential phase (A₆₀₀ = 0.8 to 1) corresponding to 1 mg of protein was filtered, and cytoplasmic content was released by osmotic downshock. Growth rates were determined independently in microplate assays, and the values are the means of triplicate experiments. Amino acid analysis was performed on an amino acid analyzer. Glycine betaine was quantified by HPLC. wt, wild type; Pro, proline; Bet, betaine. 

^bThe data represent the sum of the 19 amino acids (with proline) detected by the analysis. Data are the means of duplicate experiments. 

^c–, Value below the detection limit (<2).