Running title:
Dibutyl phthalate metabolic pathway in strain ZJUTW
Manuscript prepared for Biotechnology and Bioengineering, March,
2020.
Abstract: 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 andpht gene cluster, are located on the plasmid pQL1. Whilepca 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 betweenpht and pca clusters, which also favor ZJUTW allowing it
to efficiently degrade DBP. Combined genomic and transcriptomic analyses
affords the
complete
DBP metabolic pathway inArthrobactersp. ZJUTW that is different from that of reported otherArthrobacter 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.
Keywords :Dibutyl phthalate, genomics, transcriptomics,
biodegradation