Deciphering triterpenoid saponin biosynthesis by leveraging transcriptome response to methyl jasmonate elicitation in Saponaria vaccaria.

Methyl jasmonate (MeJA) is a known elicitor of plant specialized metabolism, including triterpenoid saponins. Saponaria vaccaria is an annual herb used in traditional Chinese medicine, containing large quantities of oleanane-type triterpenoid saponins with anticancer properties and structural similarities to the vaccine adjuvant QS-21. Leveraging the MeJA-elicited saponin biosynthesis, we identify multiple enzymes catalyzing the oxidation and glycosylation of triterpenoids in S. vaccaria. This exploration is aided by Pacbio full-length transcriptome sequencing and gene expression analysis. A cellulose synthase-like enzyme can not only glucuronidate triterpenoid aglycones but also alter the product profile of a cytochrome P450 monooxygenase via preference for the aldehyde intermediate. Furthermore, the discovery of a UDP-glucose 4,6-dehydratase and a UDP-4-keto-6-deoxy-glucose reductase reveals the biosynthetic pathway for the rare nucleotide sugar UDP-D-fucose, a likely sugar donor for fucosylation of plant natural products. Our work enables the production and optimization of high-value saponins in microorganisms and plants through synthetic biology approaches.

Incaspitolide A extracted from Carpesium cernuum induces apoptosis in vitro via the PI3K/AKT pathway in benign prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) is a common disease that occurs mainly in older men. The pathogenesis of BPH is complex and patients face a prolonged treatment course, and novel drugs with better selectivity and lower toxicity are required. Incaspitolide A (compound TMJ-12) is a germacrane-type sesquiterpenoid compound extracted from the plant Carpesium carnuum. Extracts of C. carnuum are known to exert suppressive effects on BPH-1 cells. In the present study, we investigated the molecular mechanisms underlying the suppressive effect of TMJ-12 specifically on BPH-1 cells. A cytotoxicity assay indicated that TMJ-12 inhibited BPH-1 cell proliferation, while flow cytometry assays showed that TMJ-12 induced G2/M phase cell cycle arrest and the apoptosis of BPH-1 cells. TMJ-12 was also shown to regulate the expression of several apoptosis- and cell cycle-related proteins, namely Bcl-2, Bax, Bad, Caspase-9, Caspase-3, cyclin-dependent kinase 1 (CDK1), Cyclin B1, CDC25C, and c-Myc, among others. Collapse of the mitochondrial membrane potential (ΔΨm) following exposure to TMJ-12 was detected with the JC-1 staining assay. Further investigation revealed that treatment with TMJ-12 inhibited the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway by increasing the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Taken together, the results suggest that TMJ-12 prevents BPH-1 cell proliferation via the PI3K/AKT pathway by inducing apoptosis and cell cycle arrest.

Preparation of non-sintered lightweight aggregates through co-mechanochemical treatment of oil-contaminated drill cuttings, circulation fluidized bed combustion fly ash, and quicklime.

This work investigates the feasibility of co-mechanochemical treatment of oil-contaminated drill cuttings (OCDC), circulation fluidized bed combustion (CFBC) fly ash, and quicklime to prepare non-sintered lightweight aggregates (NSLWAs). The NSLWAs with high cylinder compressive strength and low water absorption could be obtained under the condition of optimal water addition and appropriate steam-curing temperature, as well as steam-curing time. Co-mechanochemical treatment could enhance the pozzolanic reactivity of CFBC fly ash effectively, which is beneficial to the strength development of NSLWAs. Moreover, co-mechanochemical treatment also can degrade the petroleum hydrocarbon of OCDC, greatly reducing the leaching concentrations of total petroleum hydrocarbons (TPH) of NSLWAs. The final leaching concentrations of TPH are much lower than the requirements of Chinese National Standard GB 31571-2015. Graphical abstract.

Roles of B739_1343 in iron acquisition and pathogenesis in Riemerella anatipestifer CH-1 and evaluation of the RA-CH-1ΔB739_1343 mutant as an attenuated vaccine.

Iron is one of the most important elements for bacterial survival and pathogenicity. The iron uptake mechanism of Riemerella anatipestifer (R. anatipestifer, RA), a major pathogen that causes septicemia and polyserositis in ducks, is largely unknown. Here, the functions of the putative TonB-dependent iron transporter of RA-CH-1, B739_1343, in iron utilization and pathogenicity were investigated. Under iron-starved conditions, the mutant strain RA-CH-1ΔB739_1343 exhibited more seriously impaired growth than the wild-type strain RA-CH-1, and the expression of B739_1343 in the mutant strain restored growth. qRT-PCR results showed that the transcription of B739_1343 was not regulated by iron conditions. In an animal model, the median lethal dose (LD50) of the mutant strain RA-CH-1ΔB739_1343 increased more than 104-fold (1.6×1012 CFU) compared to that of the wild-type strain RA-CH-1 (1.43×108 CFU). In a duck co-infection model, the mutant strain RA-CH-1ΔB739_1343 was outcompeted by the wild-type RA-CH-1 in the blood, liver and brain of infected ducks, indicating that B739_1343 is a virulence factor of RA-CH-1. Finally, immunization with live bacteria of the mutant strain RA-CH-1ΔB739_1343 protected 83.33% of ducks against a high-dose (100-fold LD50) challenge with the wild-type strain RA-CH-1, suggesting that the mutant strain RA-CH-1ΔB739_1343 could be further developed as a potential live attenuated vaccine candidate for the duck industry.

[Effects of Longzuan Tongbi Recipe on Fas/FasL Systems in Serum and Synovium of Collagen-in- duced Arthritis Rats].

Objective To observe the effect of Longzuan Tongbi Recipe (LTR) on Fas/FasL sys- tems in serum and synovium of collagen-induced arthritis (CIA) rats. Methods Ten rats were randomly selected from 60 male Wistar rats as a normal control group. CIA model was prepared by injecting type II bovine collagen and incomplete Freund's adjuvant mixture in the rest 50 rats. After modeling rats were di- vided into the model group, the methotrexate (MTX) group, high, middle, and low dose LTR groups, 10 in each group. Normal saline was administered to rats in the model group by gastrogavage. MTX solution (0.27 mg/100 g) was administered to rats in the MTX group by gastrogavage, once per week for 4 succes- sive weeks. LTR (4.32, 2.16, 1.08 g/mL) was administered to rats in the 3 LTR groups by gastrogavage, twice per day for 30 successive days. Morphological changes of synovium were observed by HE staining. Expression levels of Fas/FasL in rat serum and synovium were quantitatively detected by ELISA. Results Normal synovium cells could be seen in the normal group. But they were obviously proliferated, fat cells in the lower synovium were reduced or deformed, fibroblasts were increased in the model group, accompa- nied with infiltration of lymphocytes and monocytes. All these changes were more obviously alleviated in the MTX group, and the 3 LTR groups. Compared withI the normal control group, Fas expression level in- creased in rat serum and synovium, serum FasL expression level decreased in the model group (P <0. 05, P <0. 01). Compared with the model group, Fas expression level decreased in rat serum and synovium in the MTX group, high and middle dose LTR groups; Fas expression level in rat serum increased in the MTX group and 3 LTR groups; Fas expression level in synovium increased in the MTX group, high and middle dose LTR groups (P <0. 05, P <0. 01). Compared with the MTX group, Fas expression level in serum of the low dose LTR group, and Fas expression level in synovium of low and middle dose LTR groups was elevat- ed; Fas expression level in serum and synovium of the high dose LTR group was reduced; FasL expres- sion level in serum and synovium of low and middle dose LTR groups was reduced; FasL expression level in serum and synovium increased of the high dose LTR group (P <0. 05, P <0. 01). Conclusion LTR could control and treat rheumatoid arthritis, and its mechanism might lie in regulating. Fas/FasL systems media- ted cell apoptosis, and relieving pathological reaction of rheumatoid arthritis.