Open AccessThe Regulation of para-Nitrophenol Degradation in Pseudomonas putida DLL-E4
Author(s) -
Qiongzhen Chen,
Hui Tu,
Xue Luo,
Biying Zhang,
Fei Huang,
Zhoukun Li,
Jue Wang,
Wenbiao Shen,
Jiale Wu,
Zhongli Cui
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0155485
Subject(s) - catabolite repression , nitrophenol , downregulation and upregulation , 4 nitrophenol , pseudomonas putida , degradation (telecommunications) , biology , biochemistry , transcriptome , chemistry , gene expression , gene , mutant , telecommunications , computer science , catalysis
Pseudomonas putida DLL-E4 can efficiently degrade para -nitrophenol and its intermediate metabolite hydroquinone. The regulation of para -nitrophenol degradation was studied, and PNP induced a global change in the transcriptome of P . putida DLL-E4. When grown on PNP, the wild-type strain exhibited significant downregulation of 2912 genes and upregulation of 845 genes, whereas 2927 genes were downregulated and 891 genes upregulated in a pnpR -deleted strain. Genes related to two non-coding RNAs ( ins1 and ins2 ), para -nitrophenol metabolism, the tricarboxylic acid cycle, the outer membrane porin OprB, glucose dehydrogenase Gcd, and carbon catabolite repression were significantly upregulated when cells were grown on para -nitrophenol plus glucose. pnpA , pnpR , pnpC1C2DECX1X2 , and pnpR1 are key genes in para -nitrophenol degradation, whereas pnpAb and pnpC1bC2bDbEbCbX1bX2b have lost the ability to degrade para -nitrophenol. Multiple components including transcriptional regulators and other unknown factors regulate para -nitrophenol degradation, and the transcriptional regulation of para -nitrophenol degradation is complex. Glucose utilization was enhanced at early stages of para -nitrophenol supplementation. However, it was inhibited after the total consumption of para -nitrophenol. The addition of glucose led to a significant enhancement in para -nitrophenol degradation and up-regulation in the expression of genes involved in para -nitrophenol degradation and carbon catabolite repression (CCR). It seemed that para -nitrophenol degradation can be regulated by CCR, and relief of CCR might contribute to enhanced para -nitrophenol degradation. In brief, the regulation of para -nitrophenol degradation seems to be controlled by multiple factors and requires further study.