Gene mining and efficient biosynthesis of a fungal peptidyl alkaloid.

Objective: Peptidyl alkaloids, a series of important natural products can be assembled by fungal non-ribosomal peptide synthetases (NRPSs). However, many of the NRPSs associated gene clusters are silent under laboratory conditions, and the traditional chemical separation yields are low. In this study, we aim to discovery and efficiently prepare fungal peptidyl alkaloids assembled by fungal NRPSs. Methods: Bioinformatics analysis of gene cluster containing NRPSs from the genome of Penicillium thymicola, and heterologous expression of the putative gene cluster in Aspergillus nidulans were performed. Isolation, structural identification, and biological evaluation of the product from heterologous expression were carried out. Results: The putative tri-modular NRPS AncA was heterologous-expressed in A. nidulans to give anacine (1) with high yield, which showed moderate and selective cytotoxic activity against A549 cell line. Conclusion: Heterologous expression in A. nidulans is an efficient strategy for mining fungal peptidyl alkaloids.

Terpenoids from Resina Commiphora Regulating Lipid Metabolism via Activating PPARα and CPT1 Expression.

Commiphoranoids A-E (1-5), five novel sesquiterpenoids, dinorditerpenoids, and heterodimers with unprecedented carbon skeletons, were isolated from Resina Commiphora. The structure of 1 was secured by X-ray crystallography. Compound 4 represents the first example of C38 terpenoids, whereas 5 is a C30 terpenoid formed by two types of sesquiterpenoids. These metabolites possess lipid regulatory activities via activating PPARα and CPT1.

Anti-Mycobacterium tuberculosis Terpenoids from Resina Commiphora.

Four new compounds including two new sesquiterpenoid dimers, commiphoroids E (1) and F (2), a new triterpenoid (3), and a new sesquiterpenoid (4), along with three known terpenoids (5-7) were isolated from Resina Commiphora, whose structures were identified by NMR spectra, HRESIMS, and X-ray diffraction analysis. Compounds 1 and 2 both bear an O-bridge ring and feature a plausible [4 + 2] Diels-Alder cycloaddition reaction. Antimycobacterial activities show that all the tested compounds (200 µM) could inhibit the growth of both sensitive and clinically multi-drug resistant (MDR) isolated strains. In addition, cellular toxicity of the isolates against human cancer cells and THP-1 monocyte cells was examined.

Discovery of Populusone, a Skeletal Stimulator of Umbilical Cord Mesenchymal Stem Cells from Populus euphratica Exudates.

Populusone (1), a cembrane-type macrocyclic trinorditerpenoid, was isolated from the exudates of Populus euphratica and shown to have an unprecedented carbon skeleton, The structure was identified using spectroscopic methods and X-ray crystallography. A possible pathway for the biosynthesis of 1 was proposed. Populusone (10 µM) was found to promote proliferation and differentiation of umbilical cord derived mesenchymal stem cells into keratinocyte like cells.

Commiphoratones A and B, Two Sesquiterpene Dimers from Resina Commiphora.

Two sesquiterpene dimers, commiphoratones A (1) and B (2), were isolated from Resina Commiphora. Their structures were elucidated by spectroscopic, computational, and crystallographic methods. Compounds 1 and 2 represent an unusual pattern of dimerization between two types of sesquiterpenes. Moreover, compound 1 has a saddle shape. The plausible biosynthetic pathway for 1 and 2 is presented. Bioassay showed that 1 and 2 significantly block lipid metabolism in a concentration-dependent manner.

Characterization of Sesquiterpene Dimers from Resina Commiphora That Promote Adipose-Derived Stem Cell Proliferation and Differentiation.

The new sesquiterpene dimers commiphoroids A-D (1-4) were isolated from Resina Commiphora, and their structures were assigned by spectroscopic methods and X-ray diffraction analysis. Compounds 1 and 2 are stereoisomers of putative [2 + 4]-cycloaddition reactions, and 3 is a trinorsesquiterpene dimer containing a 6/6/5/6/6/6 hexacyclic framework, while 4 possesses a 8-oxabicyclo[3.2.1]oct-6-ene skeletal core. Plausible biosynthetic pathways for 1-4 are proposed. Biochemical studies show that compound 1 promotes ca. 60% expression of keratinocyte-specific markers in adipose-derived stem cells at 10 µM.

Cytotoxic and renoprotective diterpenoids from Clerodendranthus spicatus.

Three new diterpenoids, spicatusenes A-C (1-3), and eleven known ones (4-14) were isolated from the aerial parts of Clerodendranthus spicatus. Their structures were identified by spectroscopic methods. The cytotoxic activities of all the compounds against human cancer cells (HL-60, SMMC-7721, A-549, MCF-7, and SW-480) were examined and found that compounds 2, 3, 6, 8, 10, and 13 were active against one or more cancer cell lines. Besides, the renoprotective effects of all the isolates in TGF-ß1-induced rat kidney fibroblasts revealed that compounds 3-7, 9, 13, and 14 were beneficial for renal fibrosis. Finally, a plausible biosynthetic pathway for 1 via a Hantzsch-type reaction was proposed.

[Induction of skin allograft tolerance in mice by using anti-alphabeta T cell receptor and anti-CD80 monoclonal antibodies combined with bone marrow transfusion].

OBJECTIVE: To explore the role of anti-alphabeta T cell receptor (TCR) and anti-CD80 monoclonal antibodies (mAbs) combined with donor bone marrow cells (BMCs) infusion in the induction of murine skin allografts tolerance. METHODS: On day 0, 2 x 10(8) BMCs of BALB/c mice were injected into recipient C57BL/6 mice via the tail vein, meanwhile, an intraperitoneal injection of TCRalphabeta mAb (500 microg) was given. On day 2, CD80 mAb was administered intraperitoneally. Skin grafting was performed on day 6. Delayed type hypersensitivity (DTH), mixed lymphocyte reaction (MLR), IL-2 reverse assay of MLR, adoptive transfer assay and chimerism detection were performed at different time points and tolerance mechanisms were investigated. RESULTS: The mean survival time (MST) of BALB/c skin allografts in C57BL/6 recipients that were treated by anti-TCRalphabeta and anti-CD80 mAbs combined with donor BMCs infusion was 70 days. DTH and MLR assay indicated that the tolerant mice displayed significant hyporesponsiveness. The result of IL-2 reverse test showed that clone anergy was probably involved in the formation of tolerance in the tolerant C57BL/6 mice. In vivo and in vitro adoptive transfer assay, suppressive activity in the spleens of tolerant C57BL/6 mice was observed. Chimerism existed in both the thymus and spleen of the tolerant C57BL/6 mice. The chimerism level gradually declined with time. CONCLUSION: Treatment of anti-TCRalphabeta and anti-CD80 mAbs combined with donor BMCs infusion can successfully induce a long-term tolerance in BALB/c mice to C57BL/6 skin graft. Multiple mechanisms, including clone anergy, suppressor cells and chimerism are involved in the tolerance.