Heterologous biosynthesis of medicarpin using engineered Saccharomyces cerevisiae.

Medicarpin is an important bioactive compound with multiple medicinal activities, including anti-tumor, anti-osteoporosis, and anti-bacterial effects. Medicarpin is associated with pterocarpans derived from medicinal plants, such as Sophora japonica, Glycyrrhiza uralensis Fisch., and Glycyrrhiza glabra L. However, these medicinal plants contain only low amounts of medicarpin. Moreover, the planting area for medicarpin-producing plants is limited; consequently, the current medicarpin supply cannot meet the high demands of medicinal markets. In this study, eight key genes involved in medicarpin biosynthesis were identified using comparative transcriptome and bioinformatic analyses. In vitro and in vivo enzymatic reaction confirmed the catalytic functions of candidate enzymes responsible for the biosynthesis of medicarpin and medicarpin intermediates. Further engineering of these genes in Saccharomyces cerevisiae achieved the heterologous biosynthesis of medicarpin using liquiritigenin as a substrate, with a final medicarpin yield of 0.82 ± 0.18 mg/L. By increasing the gene copy numbers of vestitone reductase (VR) and pterocarpan synthase (PTS), the final medicarpin yield was increased to 2.05 ± 0.72 mg/L. This study provides a solid foundation for the economic and sustainable production of medicarpin through a synthetic biology strategy.

[Correlation between rhizosphere environment and content of medicinal components of Arnebia euchroma].

This study aimed to explore the correlation between rhizosphere soil microorganisms of wild Arnebia euchroma and the content of medicinal components to provide guidance for the selection of the ecological planting base. The total DNA of rhizosphere soil microorganisms of wild A. euchroma was extracted, and the microbial community structure of rhizosphere soil microorganisms was analyzed by IlluminaMiseq high-throughput sequencing technology. The content of total hydroxynaphthoquinone pigment and ß,ß'-dimethylacrylalkannin in medicinal materials was determined by high-performance liquid chromatography(HPLC). The physicochemical pro-perties of rhizosphere soil of wild A. euchroma in main producing areas were determined, and the correlation of soil microbial abundance with index component content and soil physicochemical properties was analyzed by SPSS software. The results showed that the species composition of rhizosphere fungi and bacteria in A. euchroma from different habitats was similar at the phylum and genus levels, but their relative abundance, richness index(Chao1), and community diversity(Simpson) index were different. Correlation analysis showed that the content of available phosphorus in soil was positively correlated with the content of total hydroxynaphthoquinone pigment and ß,ß'-dimethylacrylalkannin, and the abundance of five fungal genera such as Solicoccozyma and six bacterial genera such as Pseudo-nocardia and Bradyrhizobium was positively correlated with the content of medicinal components in medicinal materials. The abundance of Bradyrhizobium was significantly positively correlated with the content of ß,ß'-dimethylacrylalkanin. The abundance of fungi such as Archaeorhizomyces was significantly positively correlated with the content of available phosphorus in rhizosphere soil, and Bradyrhizobium was significantly negatively correlated with soil pH. Therefore, the abundance of fungi and bacteria in the rhizosphere of A. euchroma has a certain correlation with the medicinal components and the physicochemical properties of the rhizosphere soil, which can provide a scientific basis for the selection of ecological planting bases in the later stage.

The complete chloroplast genome sequence of Viola kunawarensis Royle, a precious Uygur medicinal material.

Viola kunawarensis Royle is a precious Uygur medicinal material that has anti-fever and detoxifying effects. This study reports the complete chloroplast genome sequence of V. kunawarensis based on Illumina NovaSeq-PE150 platform sequencing reads. The genome is 156,837 bp long and contains a small single-copy (SSC) region of 17,059 bp and a large single-copy (LSC) region of 86,194 bp, separated by two inverted repeats (IRs) of 26,792 bp each. There are 111 unique genes in the chloroplast genome. In this study, V. kunawarensis was confirmed to be most closely related to all comprising Viola taxa except Viola mirabilis and Viola websteri.

[Environmental Behaviors of Plant Growth Regulators in Soil: A Review].

At present, plant growth regulators play an increasingly important role in global agricultural production. The average growth rate of global sales of plant growth regulators has been above 14% in the past decade. For many years, most plant growth regulators have been considered low-toxicity or slight-toxicity pesticides. However, recent studies have found that many plant growth regulators and their degradation products in the environment are potentially harmful to humans, animals, and plants. As the key factors to control the entering of plant growth regulators into the environment, the environmental behaviors of plant growth regulators in soil could make a significant influence on the risk of plant growth regulators to environmental safety. Therefore, it is critical to investigate the environmental behaviors of plant growth regulators in soil. This study systematically summarizes the environmental behaviors of plant growth regulators in soil from recent research, including the adsorption, desorption, hydrolysis, photolysis, and microbial degradation. Additionally, the factors affecting the environmental behaviors of plant growth regulators in the soil are discussed in detail. Moreover, the future research focus and direction to plant growth regulators are suggested.

The complete chloroplast genome of Humulus lupulus cv. 'Fubei-1' (Rosales: Cannabaceae).

Hop (Humulus lupulus) is a perennial plant with commercial values. Here, we reported the complete chloroplast genome for a local hop cultivar (Humulus lupulus cv. 'Fubei-1') from Xinjiang, China. The chloroplast genome is 153,614 bp long with an A + T-biased base composition, and contains a total of 113 gene species, including 79 protein-coding, 30 tRNA, and four rRNA gene species. Nineteen gene species are duplicated, and 18 gene species harbor one or two introns. Phylogenetic analysis revealed close relatedness among the three hop cultivars ('Saazer', 'Hallertauer', and 'Fubei-1').

The complete chloroplast genome sequence of Ferula sinkiangensis K. M. Shen, a precious and endangered traditional Chinese medicine.

Ferula sinkiangensis K. M. Shen is a valuable traditional Chinese medicine historically used to treat stomachache and rheumatoid arthritis. The chloroplast genome of Ferula genus plant has not been previously reported. This study reported the complete chloroplast genome sequence of F. sinkiangensis based on high-throughput sequencing. The genome was 166,583 bp in length, containing a small single-copy (SSC) region of 17,595 bp and a large single-copy (LSC) region of 85,242 bp, separated by two inverted repeats (IRs) of 31,873 bp, each. The genome contained 114 unique genes, including 80 protein-coding genes (PCGs), four rRNA genes, and 30 tRNA genes. In addition, 17 genes contained one or two introns, including nine PCG genes with a single intron, two PCG genes harboring two introns, and six tRNA genes harboring a single intron. In this study, F. sinkiangensis K. M. had the closest genetic relationship with Torilis scabra and clustered with the Umbelliferae family species.

Possibility of Combining Carbon Dots and Liquid Exfoliated Graphene as a Carbon-Based Light Addressable Potentiometric Sensor.

A light addressable potentiometric sensor (LAPS) is a versatile sensing platform for bioassay. However, the lack of carbon-based LAPS (C-LAPS) is a bottleneck for its sustainable development in a carbon electronic era. Herein, a study of C-LAPS based on the combinations of carbon dots (CDs) and liquid exfoliated graphene (LEG) is presented. Devices of C-LAPS are first fabricated by self-assembling the hydrothermally synthesized CDs and the cosolvent ultrasonic delaminated LEG on poly(diallyldimethylammonium chloride) (PDDA)-modified indium tin oxide (ITO) glasses. According to the stacking orders of CDs and LEG, C-LAPS are named as CDs/LEG@PDDA/ITO and LEG/CDs@PDDA/ITO. Then, their electronic and photoelectronic features are measured and compared with the pure CD- and pure LEG-decorated ITO electrodes. Furthermore, working mechanisms are proposed by means of the classical theories of energy band bending and built-in electric field at the heterojunction of CDs and LEG. The resemblances of CDs/LEG@PDDA/ITO-based C-LAPS with Si-based LAPS (Si-LAPS) are confirmed from the points of view of production and separation of the photogenerated carriers, the formation of photocurrent, and the distinction with LEG/CDs@PDDA/ITO. Finally, its feasibility for biological application is justified by using the immune reaction of 5-methylcytosine (5mC) and its antibody (anti-5mC) as a proof of concept. The improved linear responses are evidenced by the comparisons with Si-LAPS' results. Conclusively, the proposed C-LAPS is believed to be a candidate for traditional semiconductor-based LAPS, with the merit of solution-processable. Meanwhile, the theoretical deductions about C-LAPS' principle can also pave the way for developing similar carbon-based sensors.

Multiprobe Assay for Clinical SEPT9 Methylation Based on the Carbon Dot-Modified Liquid-Exfoliated Graphene Field Effect Transistor with a Potential to Present a Methylation Panorama.

The hypermethylation in the promoter region of the SEPT9 gene is associated with the development of colorectal cancer (CRC). Although its clinical significance for early diagnosis and screening of CRC has been demonstrated, the tedious operations in the conventional DNA methylation (DNAm) detection hinder its wide application. Herein, an electronic method for determining SEPT9 methylation in CRC patients is proposed by using the carbon dot-modified liquid exfoliated graphene field effect transistor (CDs-LEG-FET) as the DNAm sensor, the specifically designed probes to capture the SEPT9 gene and the immunologic recognition to recognize 5-methylcytosine (5mC) positions on the anchored sequences. The identification and nanomorphology of the as-prepared materials and devices are executed first by the characterizations of UV-vis, Raman, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and electronic measurements. Then, the role of CDs in enhancing DNAm sensitivity of CD-LEG-FET is manifested by comparing it with that of CD-free LEG-FET. Third, the captured SEPT9 genes on CD-LEG-FETs by different probes are evaluated, and the optimized temperature for hybridizing the target ssDNA sequences is determined to be 48 °C. Furthermore, the detection sensitivity for the low-quantity of DNA samples is demonstrated to be as low as 2 ng. Finally, the methylation degree of the tumor and corresponding noncancerous tissue DNA samples were examined by the proposed electric method and methylight assay in parallel. The diagnostic value of the electrical assay is confirmed by using the receiver operating characteristic curves; meanwhile, the superiority of the CD-LEG-FET platform is found to present a methylation panorama of the target gene.