C. Frank et al., METABOLISM OF AROMATIC-ALDEHYDES AS COSUBSTRATES BY THE ACETOGEN CLOSTRIDIUM-FORMICOACETICUM, Archives of microbiology, 170(6), 1998, pp. 427-434
When the acetogen Clostridium formicoaceticum was cultivated on mixtur
es of aromatic compounds (e.g., 4-hydroxybenzaldehyde plus vanillate),
the oxidation of aromatic aldehyde groups occurred more rapidly than
did O-demethylation. Likewise, when fructose and 4-hydroxybenzaldehyde
were simultaneously provided as growth substrates, fructose was utili
zed only after the aromatic aldehyde group was oxidized to the carboxy
l level. Aromatic aldehyde oxidoreductase activity was constitutive (a
ctivities approximated 0.8 U mg(-1)), and when pulses of 4-hydroxybenz
aldehyde were added during fructose-dependent growth, the rate at whic
h fructose was utilized decreased until 4-hydroxybenzaldehyde was cons
umed. Although 4-hydroxybenzaldehyde inhibited the capacity of cells t
o metabolize fructose, lactate or gluconate were consumed simultaneous
ly with 4-hydroxybenzaldehyde, and lactate or aromatic compounds lacki
ng an aldehyde group were utilized concomitantly with fructose. These
results demonstrate that (1) aromatic aldehydes can be utilized as cos
ubstrates and have negative effects on the homoacetogenic utilization
of fructose by C. formicoaceticum, and (2) the consumption of certain
substrates by this acetogen is not subject to catabolite repression by
fructose.