Total biosynthesis of the medicinal triterpenoid saponin astragalosides.

Astragalus membranaceus has been used in traditional Chinese medicine for over 2,000 years. Its major active triterpenoid saponins, astragalosides, have attracted great attention due to their multiple health benefits and applications in medicine. Despite this, the biosynthetic machinery for astragalosides remains enigmatic.

Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa.

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity. Given that two C-10 modified camptothecin derivatives, topotecan and irinotecan, have been approved as potent anticancer agents, there is a critical need for methods to access other aromatic ring-functionalized congeners (e.g.

Four unreported aporphine alkaloids with antifungal activities from Artabotrys hexapetalus.

In this study, the extract from Artabotrys hexapetalus showed strong antifungal activity against phytopathogenic fungi in vitro. Four unreported aporphine alkaloids, hexapetalusine A-D (1-4), were isolated from stems and roots of Artabotrys hexapetalus (L.f.

Chromosome level genome assembly of endangered medicinal plant Anisodus tanguticus.

Anisodus tanguticus is a medicinal herb that belongs to the Anisodus genus of the Solanaceae family. This endangered herb is mainly distributed in Qinghai-Tibet Plateau. In this study, we combined the Illumina short-read, Nanopore long-read and high-throughput chromosome conformation capture (Hi-C) sequencing technologies to de novo assemble the A.

First report of Fusarium ussurianum causing leaf spot on Hemerocallis citrina in Sichuan Basin of China.

Hemerocallis citrina is a popular vegetable crop in China, due to abundant nutrients in its edible flower buds. In March 2021, serious symptoms of leaf spot were observed on nearly 90% cultivated H. citrina seedlings in the fields of Dazhou city (31°17'56″ N, 107°31'59″ E), Sichuan, China.

First report of leaf spot caused by Epicoccum latusicollum on Hemerocallis citrina in China.

Hemerocallis citrina is a popular vegetable crop. Its eatable flower buds contain abundant nutrients, especially lecithin (Guo et al., 2022).

Genomic and structural basis for evolution of tropane alkaloid biosynthesis.

The tropane alkaloids (TAs) cocaine and hyoscyamine have been used medicinally for thousands of years. To understand the evolutionary origins and trajectories of serial biosynthetic enzymes of TAs and especially the characteristic tropane skeletons, we generated the chromosome-level genome assemblies of cocaine-producing (Erythroxylaceae, rosids clade) and hyoscyamine-producing (Solanaceae, asterids clade). Comparative genomic and phylogenetic analysis suggested that the lack of spermidine synthase/-methyltransferase (SPMT1) in ancestral asterids species contributed to the divergence of polyamine (spermidine or putrescine) methylation in cocaine and hyoscyamine biosynthesis.

Phytochemical Analysis of Nothapodytes tomentosa and Distribution and Content of Camptothecin and its Analogues in Four Plants.

Camptothecin (CPT) and its derivatives have attracted worldwide attention because of their notable anticancer activity. However, the growing demand for CPT in the global pharmaceutical industry has caused a severe shortage of CPT-producing plant resources. In this study, phytochemical analysis of results in the isolation and identification of CPT (13: ) and 16 analogues (1:  - 12, 14:  - 17: ), including a new (1: ) and five known (9, 10, 12, 15: , and 17: ) CPT analogues with an open E-ring.

3 and Systems Mediated Base Editing in Kiwifruit Canker Causal Agent pv. .

pv. () causes bacterial canker of kiwifruit with heavy economic losses. However, little is known about the pathogenic genes of .

Asperidulins A and B, two new prenylxanthone derivatives from an apple-derived fungus KIB-HACM-01.

Two new prenylxanthone derivatives, asperidulins A () and B (), along with a known emodin analogue () were isolated from an apple-derived fungus KIB-HACM-01. Their structures were elucidated by interpretation of HRMS, NMR, and comparisons of specific optical rotation. Asperidulin B () exhibited a moderate cytotoxicity against A549 and BEAS-2B with an IC values of 13.

Discovery and Biosynthetic Origin of Quinolizidomycins A and B, Two Quinolizidine Alkaloids from sp. KIB-1714.

Quinolizidomycins A () and B (), two unprecedented quinolizidine alkaloids featuring a tricyclic 6/6/5 ring system, were isolated from sp. KIB-1714. Their structures were assigned by detailed spectroscopic data analyses and X-ray diffraction.

Discovery and biosynthesis of karnamicins as angiotensin converting enzyme inhibitors.

Angiotensin-converting enzyme inhibitors are widely used for treatment of hypertension and related diseases. Here, six karnamicins E-E (1-6), which bear fully substituted hydroxypyridine and thiazole moieties are characterized from the rare actinobacterium Lechevalieria rhizosphaerae NEAU-A2. Through a combination of isotopic labeling, genome mining, and enzymatic characterization studies, the programmed assembly of the fully substituted hydroxypyridine moiety in karnamicin is proposed to be due to sequential operation of a hybrid polyketide synthase-nonribosomal peptide synthetase, two regioselective pyridine ring flavoprotein hydroxylases, and a methyltransferase.

-Alkylazoxymycins A-F, Naturally Occurring Azoxy-Aromatic Compounds from sp. Py50.

Six new azoxy-aromatic compounds (-alkylazoxymycins A-F, -) and two new nitrogen-bearing phenylvaleric/phenylheptanoic acid derivatives (-alkylphemycins A and B, and ) were isolated from sp. Py50. Their structures were elucidated based on HRESIMS, NMR, UV spectroscopic analyses, and X-ray crystallographic data.

Guvermectin Biosynthesis Revealing the Key Role of a Phosphoribohydrolase and Structural Insight into the Active Glutamate of a Noncanonical Adenine Phosphoribosyltransferase.

Guvermectin is a novel plant growth regulator that has been registered as a new agrochemical in China. It is an adenosine analogue with an unusual psicofuranose instead of ribose. Herein, the gene cluster responsible for guvermectin biosynthesis in NEAU6 is identified using gene interruption and heterologous expression experiments.

Novel Plant Growth Regulator Guvermectin from Plant Growth-Promoting Rhizobacteria Boosts Biomass and Grain Yield in Rice.

Food is a fundamental human right, and global food security is threatened by crop production. Plant growth regulators (PGRs) play an essential role in improving crop yield and quality, and this study reports on a novel PGR, termed guvermectin (GV), isolated from plant growth-promoting rhizobacteria, which can promote root and coleoptile growth, tillering, and early maturing in rice. GV is a nucleoside analogue like cytokinin (CK), but it was found that GV significantly promoted root and hypocotyl growth, which is different from the function of CK in .

Discovery and Engineering of the Cocaine Biosynthetic Pathway.

Cocaine, the archetypal tropane alkaloid from the plant genus , has recently been used clinically as a topical anesthesia of the mucous membranes. Despite this, the key biosynthetic step of the requisite tropane skeleton (methylecgonone) from the identified intermediate 4-(1-methyl-2-pyrrolidinyl)-3-oxobutanoic acid (MPOA) has remained, until this point, unknown. Herein, we identify two missing enzymes (CYP81AN15 and MT4) necessary for the biosynthesis of the tropane skeleton in cocaine by transient expression of the candidate genes in .

Bioproduction of monoterpene indole alkaloids in a single cell factory.

The biosynthesis of vindoline and catharanthine, the direct precursors used for industrial production of the anti-cancer drug vinblastine, has been achieved in the yeast cell factory. To date, this is the longest natural product biosynthesis pathway that has been successfully transferred from plants to microorganisms, indicating the possibility of producing more than 3,000 other monoterpene indole alkaloids in yeast by synthetic genome engineering.

Genomic Variation and Host Interaction among pv. Strains in 'Hongyang'.

Kiwifruit bacterial canker is a recent epidemic disease caused by pv. (), which has undergone worldwide expansion in a short time and resulted in significant economic losses. 'Hongyang' (), a widely grown cultivar because of its health-beneficial nutrients and appreciated red-centered inner pericarp, is highly sensitive to .

Isolation and biosynthesis of daturamycins from sp. KIB-H1544.

Two novel diarylcyclopentenones daturamycin A and B ( and ), and one new -terphenyl daturamycin C (), along with three known congeners (-), were isolated from a rhizosphere soil-derived sp. KIB-H1544. The structures of new compounds were elucidated via a joint use of spectroscopic analyses and single-crystal X-ray diffractions.

Catalytic innovation underlies independent recruitment of polyketide synthases in cocaine and hyoscyamine biosynthesis.

Tropane alkaloids such as hyoscyamine and cocaine are of importance in medicinal uses. Only recently has the hyoscyamine biosynthetic machinery become complete. However, the cocaine biosynthesis pathway remains only partially elucidated.

Products distribution during in situ and ex situ catalytic fast pyrolysis of Chinese herb residues.

Catalytic fast pyrolysis (CFP) for biomass treatment is a research hotspot but there is little information about the difference between the in situ and ex situ methods. In present work, the Ni-Fe/CaO-AlO catalysts with different Ni/Fe ratios have been synthesized by coprecipitation method, and the product distribution about the Chinese herb residue (CHR) catalytic fast pyrolysis by in situ and ex situ methods in a quartz tube reactor system has been investigated. The results show that the CFP pyrolysis would upgrade the quality of bio-oil but decrease the yields, no matter in situ or ex situ CFP process.

Isolation and Biosynthesis of Phenazine-Polyketide Hybrids from sp. KIB-H483.

A phenazine-polyketide hybrid compound, nexphenazine A (), was isolated from sp. KIB-H483. The bioinformatic analysis of the draft genome of the producing strain and gene inactivation experiments revealed that the biosynthesis of involves a phenazine-polyketide hybrid gene cluster.