sb9b00515_si_001.pdf (610.01 kB)
Designing an Artificial Pathway for the Biosynthesis of a Novel Phenazine N‑Oxide in Pseudomonas chlororaphis HT66
journal contribution
posted on 2020-03-26, 19:08 authored by Shuqi Guo, Rongfeng Liu, Wei Wang, Hongbo Hu, Zhiyong Li, Xuehong ZhangAromatic N-oxides are valuable due to their versatile
chemical, pharmaceutical, and agricultural applications. Natural phenazine N-oxides possess potent biological activities and can be
applied in many ways; however, few N-oxides have
been identified. Herein, we developed a microbial system to synthesize
phenazine N-oxides via an artificial
pathway. First, the N-monooxygenase NaphzNO1 was
predicted and screened in Nocardiopsis sp. 13–12–13
through a product comparison and gene sequencing. Subsequently, according
to similarities in the chemical structures of substrates, an artificial
pathway for the synthesis of a phenazine N-oxide
in Pseudomonas chlororaphis HT66 was designed and
established using three heterologous enzymes, a monooxygenase (PhzS)
from P. aeruginosa PAO1, a monooxygenase (PhzO) from P. chlororaphis GP72, and the N-monooxygenase
NaphzNO1. A novel phenazine derivative, 1-hydroxyphenazine N′10-oxide, was obtained in an engineered strain, P. chlororaphis HT66-SN. The phenazine N-monooxygenase NaphzNO1 was identified by metabolically engineering
the phenazine-producing platform P. chlororaphis HT66.
Moreover, the function of NaphzNO1, which can catalyze the conversion
of 1-hydroxyphenazine but not that of 2-hydroxyphenazine, was confirmed in vitro. Additionally, 1-hydroxyphenazine N′10-oxide demonstrated substantial cytotoxic activity against
two human cancer cell lines, MCF-7 and HT-29. Furthermore, the highest
microbial production of 1-hydroxyphenazine N′10-oxide
to date was achieved at 143.4 mg/L in the metabolically engineered
strain P3-SN. These findings demonstrate that P. chlororaphis HT66 has the potential to be engineered as a platform for phenazine-modifying
gene identification and derivative production. The present study also
provides a promising alternative for the sustainable synthesis of
aromatic N-oxides with unique chemical structures
by N-monooxygenase.
History
Usage metrics
Categories
Keywords
PAOGPchlororaphis HT 66.chlororaphis HT 66monooxygenase NaphzNO 1Pseudomonas chlororaphis HT 66 Aromatic Nhydroxyphenazinemonooxygenase NaphzNO 1.phenazine-producing platform Pphenazine NNatural phenazine Nchemical structuresphenazine-modifying gene identificationstrain P 3-SNchlororaphis HT 66-SNoxide1-cancer cell linesPseudomonas chlororaphis HT 66MCF
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC