TABLE 2.

β-Galactosidase activity of the S. meliloti Rm5000 strain carrying a hutX-lacZ fusion integrated into the chromosome (strain Rm HZ240) under various physiological conditions^a

Culture condition	β-Galactosidase activity (Miller units)
Control	39
NaCl (0.3 M)	12
Glycine betaine	22
Proline	27
Proline betaine	29
Histidine	204

^aCells were grown in a low-osmolarity M9 minimal medium (Control). Betaines and amino acids were added at a final concentration of 1 mM. Values are means from duplicates of three independent cultures.