After the disruption of the mycelium from the isolates
grown in phenol, the extracts were incubated in the presence
of catechol, resulting in increases in the absorbance at 260
nm (Table 3), probably due to yield of cis,cis-muconic acid
[8]. Meta-cleavage activity was not detectable. A product
with an identical catechol peak was obtained from chromatographic
analysis of these samples (data not shown). These
results suggest phenol metabolism throughout occurred via
ortho fission of catechol. Activity of phenol hydroxylase
was also observed. Isolates LA5, FIB4, AE2 and FE11
that presented the highest degradation rates in 10 mM of
phenol, also presented higher activities of enzymes phenol
hydroxylase and catechol 1,2-dioxygenase. The activities
of phenol-degrading enzymes of strain FIB4 were 1.5 times
higher than those of strain LA5 and AE2 and FE11. This
difference could explain the higher values of phenol degradation
rates showed by strain FIB4 grown on up to 10
mM phenol and resulted in an increase of phenol tolerance
(Fig. 1).
After the disruption of the mycelium from the isolates
grown in phenol, the extracts were incubated in the presence
of catechol, resulting in increases in the absorbance at 260
nm (Table 3), probably due to yield of cis,cis-muconic acid
[8]. Meta-cleavage activity was not detectable. A product
with an identical catechol peak was obtained from chromatographic
analysis of these samples (data not shown). These
results suggest phenol metabolism throughout occurred via
ortho fission of catechol. Activity of phenol hydroxylase
was also observed. Isolates LA5, FIB4, AE2 and FE11
that presented the highest degradation rates in 10 mM of
phenol, also presented higher activities of enzymes phenol
hydroxylase and catechol 1,2-dioxygenase. The activities
of phenol-degrading enzymes of strain FIB4 were 1.5 times
higher than those of strain LA5 and AE2 and FE11. This
difference could explain the higher values of phenol degradation
rates showed by strain FIB4 grown on up to 10
mM phenol and resulted in an increase of phenol tolerance
(Fig. 1).
การแปล กรุณารอสักครู่..
