Development of a robust and efficient virus-induced gene silencing system for reverse genetics in recalcitrant Camellia drupifera capsules.

Background: Virus-induced gene silencing (VIGS) is a rapid and powerful method for gene functional analysis in plants that pose challenges in stable transformation. Numerous VIGS systems based on Agrobacterium infiltration has been widely developed for tender tissues of various plant species, yet none is available for recalcitrant perennial woody plants with firmly lignified capsules, such as tea oil camellia. Therefore, there is an urgent need for an efficient, robust, and cost-effective VIGS system for recalcitrant tissues.

Biosynthesis of a Bioactive Meroterpene Bakuchiol in Yeast.

Bakuchiol (BAK), a specialized meroterpene, is known for its valuable biological properties and has recently gained prominence in cosmetology for its retinol-like functionality. However, low abundance in natural sources leads to environmentally unfriendly and unsustainable practices associated with crop-based manufacturing and chemical synthesis. Here, we identified a prenyltransferase (PT) from that catalyzes the reverse geranylation of a nonaromatic carbon in -coumaric acid (-CA), coupled with a decarboxylation step to form BAK.

[Corrigendum] Hispolon inhibits breast cancer cell migration by reversal of epithelial‑to‑mesenchymal transition via suppressing the ROS/ERK/Slug/E‑cadherin pathway.

Subsequently to the publication of the above paper, an interested reader drew to the authors' attention that, with the cell migration assay data shown in Fig. 7 on p. 901, the "TPA" and "TPA + U0126" panels were strikingly similar, such that data which were intended to show the results from differently performed experiments had apparently been derived from the same original source.

Stepwise increase of fidaxomicin in an engineered heterologous host through multi-level metabolic engineering.

The anti- infection (CDI) drug fidaxomicin is a natural polyketide metabolite mainly produced by , such as , , and . In the present study, we employed a stepwise strategy by combining heterologous expression, chassis construction, promoter engineering, activator and transporters overexpression, and optimization of fermentation media for high-level production of fidaxomicin. The maximum yield of 384 mg/L fidaxomicin was achieved with engineered D7-VHb in 5 L-tank bioreactor, and it was approximately 15-fold higher than the native strain YP-1 with higher strain stability and growth rate.

A Novel ZnCys Transcription Factor, TopC, Positively Regulates Trichodin A and Asperpyridone A Biosynthesis in .

Asperpyridone A represents an unusual class of pyridone alkaloids with demonstrated potential for hypoglycemic activity, primarily by promoting glucose consumption in HepG2 cells. Trichodin A, initially isolated from the marine fungus Trichoderma sp. strain MF106, exhibits notable antibiotic activities against .

Daptomycin production enhancement by ARTP mutagenesis and fermentation optimization in Streptomyces roseosporus.

Aims: We evaluated whether the randomness of mutation breeding can be regulated through a double-reporter system. We hope that by establishing a new precursor feeding strategy, the production capacity of industrial microorganisms after pilot scale-up can be further improved.

Methods And Results: In this study, the industrial strain Streptomyces roseosporus L2796 was used as the starter strain for daptomycin production, and a double-reporter system with the kanamycin resistance gene Neo and the chromogenic gene gusA was constructed to screen for high-yield strain L2201 through atmospheric and room temperature plasma (ARTP).

Production improvement of FK506 in Streptomyces tsukubaensis by metabolic engineering strategy.

Aims: Study of the effect of isoleucine on the biosynthesis of FK506 and modification of its producing strain to improve the production of FK506.

Methods And Results: Metabolomics analysis was conducted to explore key changes in the metabolic processes of Streptomyces tsukubaensis Δ68 in medium with and without isoleucine. In-depth analysis revealed that the shikimate pathway, methylmalonyl-CoA, and pyruvate might be the rate-limiting factors in FK506 biosynthesis.

Metagenomics-metabolomics analysis of microbial function and metabolism in petroleum-contaminated soil.

Contamination of soil by petroleum is becoming increasingly serious in the world today. However, the research on gene functional characteristics, metabolites and distribution of microbial genomes in oil-contaminated soil is limited. Considering that, metagenomic and metabonomic were used to detect microbes and metabolites in oil-contaminated soil, and the changes of functional pathways were analyzed.

Identification and Characterization of a New Regulator, TagR, for Environmental Stress Resistance Based on the DNA Methylome of Streptomyces roseosporus.

DNA methylation is a defense that microorganisms use against extreme environmental stress, and improving resistance against environmental stress is essential for industrial actinomycetes. However, research on strain optimization utilizing DNA methylation for breakthroughs is rare. Based on DNA methylome analysis and KEGG pathway assignment in Streptomyces roseosporus, we discovered an environmental stress resistance regulator, TagR.

Degradation mechanism of AtrA mediated by ClpXP and its application in daptomycin production in Streptomyces roseosporus.

The efficiency of drug biosynthesis depends on different transcriptional regulatory pathways in Streptomyces, and the protein degradation system adds another layer of complexity to the regulatory processes. AtrA, a transcriptional regulator in the A-factor regulatory cascade, stimulates the production of daptomycin by binding to the dptE promoter in Streptomyces roseosporus. Using pull-down assays, bacterial two-hybrid system and knockout verification, we demonstrated that AtrA is a substrate for ClpP protease.

m4C DNA methylation regulates biosynthesis of daptomycin in L30.

Despite numerous studies on transcriptional level regulation by single genes in drug producing , the global regulation based on epigenetic modification is not well explored. N4-methylcytosine (m4C), an abundant epigenetic marker in ' genome, but its regulatory mechanism remains unclear. In this study, we identify a m4C methyltransferase (SroLm3) in L30 and multi-omics studies were performed and revealed SroLm3 as a global regulator of secondary metabolism.

Gram-Level Production of Balanol through Regulatory Pathway and Medium Optimization in Herb Fungus .

As a potential protein kinase C inhibitor, the fungus metabolite balanol has become more attractive in recent decades. In our previous work, we revealed its biosynthetic pathway through overexpression of the cluster-situated regulator gene in Chinese herb fungus . However, information on the regulation of is still largely unknown.

Activation and Characterization of Lanthomicins A-C by Promoter Engineering in L10.

The emergence of drug resistance highlights the importance of new drug discovery. Microbial secondary metabolites encoded in biosynthetic gene clusters (BGCs) are a prolific source of drugs, whereas most of these BGCs are cryptic. Thus, taking strategies to activate these cryptic BGCs is of great importance for potential drug discovery.

Improving the Yield and Quality of Daptomycin in by Multilevel Metabolic Engineering.

Daptomycin is a cyclic lipopeptide antibiotic with a significant antibacterial action against antibiotic-resistant Gram-positive bacteria. Despite numerous attempts to enhance daptomycin yield throughout the years, the production remains unsatisfactory. This study reports the application of multilevel metabolic engineering strategies in to reconstruct high-quality daptomycin overproducing strain L2797-VHb, including precursor engineering (i.

A novel strategy of gene screen based on multi-omics in Streptomyces roseosporus.

Daptomycin is a new lipopeptide antibiotic for treatment of severe infection caused by multi-drug-resistant bacteria, but its production cost remains high currently. Thus, it is very important to improve the fermentation ability of the daptomycin producer Streptomyces roseosporus. Here, we found that the deletion of proteasome in S.

Redirection of acyl donor metabolic flux for lipopeptide A40926B0 biosynthesis.

The metabolic flux of fatty acyl-CoAs determines lipopeptide biosynthesis efficiency, because acyl donor competition often occurs from polyketide biosynthesis and homologous pathways. We used A40926B0 as a model to investigate this mechanism. The lipopeptide A40926B0 with a fatty acyl group is the active precursor of dalbavancin, which is considered as a new lipoglycopeptide antibiotic.

Directed Evolution of a Nonheme Diiron N-oxygenase AzoC for Improving Its Catalytic Efficiency toward Nitrogen Heterocycle Substrates.

The azoxy compounds with an intriguing chemical bond [-N=N(-O)-] are known to have broad applications in many industries. Our previous work revealed that a nonheme diiron N-oxygenase AzoC catalyzed the oxidization of amino-group to its nitroso analogue in the formation of azoxy bond in azoxymycins biosynthesis. However, except for the reported pyridine alkaloid azoxy compounds, most azoxy bonds of nitrogen heterocycles have not been biosynthesized so far, and the substrate scope of AzoC is limited to -aminobenzene-type compounds.

The complete chloroplast genome sequence of (Annonaceae).

(Annonaceae) is endemic to China, this plant has high medicinal value and broad application prospect. In this study, we assembled and systematically analyzed the chloroplast genome of on the basis of DNA sequencing using high-throughput techniques. The chloroplast sequence of was 178,195 bp in length, including two inverted repeat regions of 42,150 bp, a large single-copy region of 90,797 bp and a small single-copy region of 3098 bp.

Cadmium-induced ultrastructural changes and apoptosis in the gill of freshwater mussel Anodonta woodiana.

This study investigated the acute toxicity of cadmium (Cd) to the freshwater mussel Anodonta woodiana. The freshwater mussels were exposed to five concentrations of Cd (0 mg/L, 8.43 mg/L, 16.

Strategy for Producing the High-Quality Glycopeptide Antibiotic A82846B in Based on the CRISPR-Cas12a System.

Oritavancin is a new-generation semisynthetic lipoglycopeptide antibiotic used to prevent the spread of vancomycin-resistant Gram-positive bacteria. The glycopeptide A82846B is the direct precursor of oritavancin. Considering the structural similarity between A82846B and vancomycin, the vancomycin producer was used as a chassis for the construction of a strain producing high-quality A82846B.

Improvement of FK506 production via metabolic engineering-guided combinational strategies in Streptomyces tsukubaensis.

Background: FK506, a macrolide mainly with immunosuppressive activity, can be produced by various Streptomyces strains. However, one of the major challenges in the fermentation of FK506 is its insufficient production, resulting in high fermentation costs and environmental burdens. Herein, we tried to improve its production via metabolic engineering-guided combinational strategies in Streptomyces tsukubaensis.

Rational engineering strategies for achieving high-yield, high-quality and high-stability of natural product production in actinomycetes.

Actinomycetes are recognized as excellent producers of microbial natural products, which have a wide range of applications, especially in medicine, agriculture and stockbreeding. The three main indexes of industrialization (titer, purity and stability) must be taken into overall consideration in the manufacturing process of natural products. Over the past decades, synthetic biology techniques have expedited the development of industrially competitive strains with excellent performances.

Activation and discovery of tsukubarubicin from Streptomyces tsukubaensis through overexpressing SARPs.

Genome sequencing has revealed that each Streptomyces contains a wide range of biosynthetic gene clusters (BGCs) and has the capability to produce more novel natural products than what is expected. However, most gene clusters for secondary metabolite biosynthesis are cryptic under normal growth conditions. In Streptomyces tsukubaensis, combining overexpression of the putative SARPs (Streptomyces antibiotic regulatory proteins) and bioactivity-guided screening, the silent gene cluster (tsu) was successfully activated and a novel bioactive anthracycline tsukubarubicin was further isolated and identified.