FIG 7 .

(A) Dehydrogenase activities toward methanol and formaldehyde in the cell-free extracts of strain 22A grown on methanol or succinate, in the presence of 30 µM CaCl₂, and in the absence and presence of LaCl₃. Activities were determined from three biological and three technical replicates. n.d., not detected. Error bars show the standard error of the mean (n = 3). (B) Formaldehyde production and degradation by resting cells of strain 22A pregrown on methanol in the absence and presence of La³⁺. Production (a) and degradation (b) of formaldehyde by strain 22A cells were measured. Strain 22A was pregrown on methanol in the absence (circles) and presence (squares) of LaCl₃. Autoclave-killed cells were used as controls (closed symbols). The molar amounts of formaldehyde in the 200-µl reaction mixture in 96-well plates were normalized by total cell numbers (10⁵ cells). Asterisks indicate statistical significance: **, P < 0.01; ***, P < 0.001; and ****, P < 0.0001 (Sidak’s multiple-comparison test).