The
s-triazine herbicide, atrazine, has been well
acknowledged as an important source causing contamination
of soil, water, and sediment. Functional bacteria are
one of the critical candidates for removing residual atrazine
from contaminated environments. Here, seven bacterial
strains showing atrazine-degrading ability were isolated
from long-term atrazine-contaminated corn field and
identified based on 16S rRNA gene sequencing. Among
these bacterial isolates, a bacterium, later designated as
Arthrobacter
sp. C3, was found to be capable of completely
degrading 25 mg/l atrazine. The high-performance
liquid chromatography–mass spectrometry (HPLC–MS)
analysis indicated that the atrazine was dechlorinated to
hydroxyatrazine, a non-phytotoxic compound. The functional
gene,
trzN, which participates in the first step of
atrazine degradation was successfully amplified and
showed high similarity to the known
trzN genes from
different bacterial genera. Based on the HPLC–MS and the
functional gene analysis, the functional bacterium C3 was
speculated to degrade atrazine via dechlorination, which
detoxified the herbicide. This study suggested a great
potential of
Arthrobacter sp. C3 to be used in indigenous
bioremediation of atrazine in field.
