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Dinitrotoluene sulfonates (DNTS) as the major toxic compounds in 2,4,6-trinitrotoluene (TNT) red water-contaminated soil threaten human health and environmental safety and are hardly degraded by common soil microorganisms. Thus, isolation and characterization of the microbes with high DNTS-degrading ability is the crucial first step for bioremediation of TNT red water-contaminated sites. Here, a novel bacterial strain, namely Bacillus altitudinis D47, with a high capacity to biodegrade DNTS was isolated and identified from the TNT red water-contaminated soil. The result showed that DNTS content was reduced to 2.05% of the original amount after 3 days inoculation with B. altitudinis D47. LC-MS/MS analysis of DNTS degradation metabolites revealed B. altitudinis D47 reduced nitro-groups on DNTS to hydroxylamino- and/or amino-groups through the activity of nitroreductase (NR). Furthermore, the genome of B. altitudinis D47 was sequenced and assembled, and six NRs were retrieved in the genome. Transcriptomic analysis showed the expression of five NRs was significantly upregulated in DNTS-treated B. altitudinis D47. The enzymatic activity assay of recombinant NR proteins validated that NR1-6 can catalyze nitro reduction of DNTS in vitro. Finally, the addition of B. altitudinis D47 remarkably alleviated the phytotoxicity of DNTS to alfalfa. Overall, our work provides insights into the characteristics and molecular mechanism of B. altitudinis D47 for biodegradation of DNTS and suggests its potential application of B. altitudinis D47 in the bioremediation of TNT red water-contaminated soil. [Display omitted] • A novel Bacillus altitudinis D47 with high DNTS-degrading ability was isolated. • Nitroreductases of B. altitudinis D47 function in the nitroreduction of DNTS. • B. altitudinis D47 treatment alleviated the toxicity of DNTS to plant significantly. [ABSTRACT FROM AUTHOR]

Monochasma savatieri Franch. ex Maxim is a perennial medicinal plant with antibiotic properties. However, the current M. savatieri resources cannot meet the increasing market demand. Thus, an advanced bioengineering technology platform is required for breeding novel and high-yielding M. savatieri germplasm/cultivars with high value. In the present study, a hairy root system induced by Agrobacterium rhizogenes , which is often used as a model to study root function and bioactive compound production, was established for M. savatieri for the first time. The hairy root induction frequencies of the different explants ranged from 4.6% to 68.3% after infection with A. rhizogenes strain LBA9402. Furthermore, many co-transformed hairy root lines using the binary vector pEG100–35S::GFP were generated. Fluorescence microscopy revealed that GFP was expressed in 72.9% of the transgenic hairy root lines. After six months, the co-transformed hairy root lines were able to grow into transgenic plantlets on medium containing cytokinin. In addition, to construct a gene editing system for M. savatieri, the tRNA-target-gRNA cassette was cloned into the pRGEB31 vector with AtU6-sgRNA and hSpCas9 backbones. The cellulose synthase-like D (CSLD2/3) genes were used as markers to assess the gene editing efficiency of the CRISPR/Cas9 vector in M. savatieri. The results showed that the CSLD2/3 sequences were altered in 11 out of 59 co-transformed hairy root lines. This study successfully established a genome editing platform for M. savatieri , for the first time, using the A. rhizogenes -mediated co-transformation system. This will enable the development of novel M. savatieri germplasm/cultivars for facility cultivation and exploitation of its medicinal value in the future. [Display omitted] • The hairy root system of Monochasma savatieri was established for the first time. • 73% of the transgenic hairy root lines were co-transformants. • CRISPR/Cas9-mediated Monochasma savatieri mutants were successfully generated. [ABSTRACT FROM AUTHOR]

The workflow of this new strategy for the metabolic phenotype analysis of PPP. A. the biosynthesis relationship of PPP was summarized via the chemical structures of involved metabolites. B. the 103 key metabolites that reflect the metabolic phenotype of PPP were chosen to construct a structural periodic table according to their biosynthesis relationship. C. the characteristics of metabolic phenotype targeting PPP were elucidated according to the heatmap of metabolites filled in the structural periodic table. [Display omitted] • A method template for high resolution of metabolic phenotype analysis targeting PPP was conducted based on accurate qualification and quantification of 103 structural associated metabolites via liquid chromatography tandem mass spectrometry. • The delicate spatial-temporal metabolic balance of PPP from ginkgo biloba can be elucidated via this method. • It is first confirmed that the salt and draught stresses could redirect the biosynthesis trend of PPP in soybean leaves to produce more isoflavones through this method. The phenylpropane pathway (PPP) is one of the most extensively investigated metabolic routes. This pathway biosynthesizes many important active ingredients such as phenylpropanoids and flavonoids that affect the flavor, taste and nutrients of food. How to elucidate the metabolic phenotype of PPP is fundamental in food research and development. In this study, we designed a structural periodical table filled with 103 metabolites produced from PPP. All of them especially the 62 structural isomers were qualified and quantified with high resolution and sensitivity via multiple reaction mode in liquid chromatography tandem triple quadrupole mass spectrometry. Ginkgo biloba and soybean were used as samples for the practical application of this method: The delicate spatial-temporal metabolic balance of PPP from ginkgo biloba has been first elucidated; It is first confirmed that the salt and draught stresses could redirect the biosynthesis trend of PPP to produce more isoflavones in soybean leaves. [ABSTRACT FROM AUTHOR]