Combined genomic and transcriptomic analysis of Dibutyl phthalate
metabolic pathway in Arthrobacter sp. ZJUTW
Dibutyl phthalate (DBP) is an environmental pollutant that can threaten
human health. The strain Arthrobacter sp. ZJUTW, isolated from the
sludge of river of Hangzhou city, can efficiently degrade DBP. Its
genomic and transcriptomic differences when cultivated with DBP and with
glucose revealed specific DBP metabolic pathways in the ZJUTW strain.
The degrading gene clusters distribute separately on a circular
chromosome and a plasmid pQL1. Genes related to the initial steps of DBP
degradation from DBP to phthalic acid (PA), the pehA gene and pht gene
cluster, are located on the plasmid pQL1. While pca gene cluster related
to the transforming of protocatechuic acid (PCA) to acetyl-CoA, is
located on the chromosome. After homologous alignment analysis with the
reported gene clusters, we found that there were a series of double
copies of homologous genes in pht and pca gene clusters that contribute
to the efficient degradation of DBP by ZJUTW. In addition,
transcriptomic analysis showed a synergistic effect between pht and pca
clusters, which also favor ZJUTW allowing it to efficiently degrade DBP.
Combined genomic and transcriptomic analyses affords the complete DBP
metabolic pathway in Arthrobacter sp. ZJUTW that is different from that
of reported other Arthrobacter strains. After necessary modification
based on its metabolic characteristics, Arthrobacter sp. ZJUTW or its
mutants might represent promising candidates for use in the
bioremediation of DBP pollution.