Programmed necrosis, necroptosis, is considered to be a highly immunogenic activity, often mediated via the release of damage-associated molecular patterns (DAMPs). Interestingly, enhanced macroautophagic/autophagic activity is often found to be accompanied by necroptosis. However, the possible role of autophagy in the immunogenicity of necroptotic death remains largely obscure. In this study, we investigated the possible mechanistic correlation between phytochemical shikonin-induced autophagy and the shikonin-induced necroptosis for tumor immunogenicity. We show that shikonin can instigate RIPK1 (receptor [TNFRSF]-interacting serine-threonine kinase 1)- and RIPK3 (receptor-interacting serine-threonine kinase 3)-dependent necroptosis that is accompanied by enhanced autophagy. Shikonin-induced autophagy can directly contribute to DAMP upregulation. Counterintuitively, among the released and ectoDAMPs, only the latter were shown to be able to activate the cocultured dendritic cells (DCs). Interruption of autophagic flux via chloroquine further upregulated ectoDAMP activity and resultant DC activation. For potential clinical application, DC vaccine preparations treated with tumor cells that were already pretreated with chloroquine and shikonin further enhanced the antimetastatic activity of 4T1 tumors and reduced the effective dosage of doxorubicin. The enhanced immunogenicity and vaccine efficacy obtained via shikonin and chloroquine cotreatment of tumor cells may thus constitute a compelling strategy for developing cancer vaccines via the use of a combinational drug treatment.

Monacolin K is a secondary metabolite synthesized by polyketide synthases (PKS) from Monascus. The monacolin K biosynthetic gene cluster, mokA-mokI, has been characterized in Monascus pilosus. The mokH gene encoding Zn(II)2Cys6 binuclear DNA binding protein is assumed to be an activator for monacolin K production. In this study, the mokH gene was cloned and driven by the glyceraldehyde-3-phosphate dehydrogenase (gpd) promoter for overexpression in M. pilosus. The transformants containing an extra copy of the mokH gene were obtained and verified by PCR and Southern hybridization. The transcripts of mokH in the transformants were expressed significantly higher than those of the wild-type strain. The transformants were stably inherited through the next generation, as determined by observation of the enhanced green fluorescent protein (EGFP). The transformant T-mokH1 also showed a 1.7-fold higher production of monacolin K than the wild-type strain in a time course analysis. Analysis of the RT-PCR products demonstrated that the monacolin K biosynthetic genes in the transformant were expressed to a greater extent than those in the wild-type strain. These results indicated that mokH upregulated the transcription of monacolin K biosynthetic genes and increased monacolin K production.

Three new compounds, hypoxyloamide (1), 8-methoxynaphthalene-1,7-diol (2), and hypoxylonol (3), together with seven compounds isolated from nature for the first time, investiamide (4), hypoxypropanamide (5), hypoxylonol A (6), investienol (7), 2-heptylfuran (8), (3S)-5-methyl-8-O-methylmellein (9), (4R)-O-methylsclerone (10), along with 19 known compounds, 11-29, were isolated from the culture broth of Hypoxylon investiens BCRC 10F0115, a fungal endophyte residing in the stems of an endemic Formosan plant Litsea akoensis var. chitouchiaoensis. The structures of the new compounds were established by spectroscopic methods, including UV, IR, HR-ESI-MS, and extensive 1D- and 2D-NMR techniques. Of these isolates, 2, 8-methoxynaphthalen-1-ol (15), and 1,8-dimethoxynaphthalene (16) showed nitric oxide (NO) inhibitory activity with IC50 values of 11.8±0.9, 17.8±1.1, and 13.3±0.5 μM, respectively, stronger than the positive control quercetin (IC50 36.8±1.3 μM). Compounds 2, 15, and 16 also showed interleukin-6 (IL-6) inhibitory activity with IC50 values of 9.2±1.7, 18.0±0.6, and 2.0±0.1 μM, stronger than the positive control quercetin (IC50 31.3±1.6 μM). To the best of our knowledge, this is the first report on guaiane sesquiterpene metabolites, 3, 6, and 7, from the genus Hypoxylon.

Seven new metabolites, including three sesquiterpenoids, 10‐hydroxythujopsene (1), akotriol (2), and xylaritriol (3), one diterpenoid, cubentriol (4), one aliphatic derivative, akoenic acid (5), one alkaloid, akodionine (6), and one isocoumarin, akolitserin (7), together with seven known compounds, 8–14, were isolated from the AcOEt‐soluble fraction of the fermentation broth of the endophytic fungus Xylaria cubensis, derived from the leaves of Litsea akoensis Hayata (Lauraceae). Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and by HR‐ESI‐MS mass spectrometry. Among the isolates, (−)‐(R)‐7‐hydroxymellein showed IL‐6 inhibitory activity with an IC50 value of 9.41 μM.

No abstract

Strain 06168H-1 was isolated from a fishpond sediment sample collected from the southern area of Taiwan, and a polyphasic approach was used to determine its taxonomic position. The isolate grew between 20-40 °C and 0-8 % (w/v) NaCl. It produced branched and unfragmented substrate mycelia. Short spore chains (3-10 spores per chain) formed on branched aerial mycelia. The spore chains contained non-motile, smooth-surfaced, oval spores. Galactose, arabinose and ribose were the whole-cell sugars and meso-diaminopimelic acid was present in its peptidoglycan. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylcholine, hydroxyphosphati dylethanolamine and a ninhydrin-positive phosphoglycolipid. The predominant menaquinone was MK-9(H4) and minor components were MK-8(H4) and MK-9(H6). Mycolic acids were not detected. The major cellular fatty acids were iso-C16 : 0 and C17 : 1ω6c and C17 : 0ω8c. The DNA G+C content of the strain was 70.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed this strain clustered with the members of the genus Saccharomonospora and was closely related to Saccharomonospora xinjiangensis, Saccharomonospora azurea and Saccharomonosporacyanea. The levels of similarity between this strain and the closely related species were: Sxinjiangensis BCRC16887, 98.34 %; S. azurea BCRC 16220, 98.27 %; and S. cyanea BCRC 16886, 97.99 %. Based on phylogenetic characteristics, strain 06168H-1 represents a novel species of the genus Saccharomonospora. We thus propose the name Saccharomonospora piscinae sp. nov. for this novel strain, with strain 06168H-1 (=BCRC 16893=KCTC 19743) as the type strain.

Pang (2020): Salinity, pH and temperature growth ranges of Halophytophthora isolates suggest their physiological adaptations to mangrove environments, Mycology,

Cultivation of the fungal strain Annulohypoxylon ilanense, an endophytic fungus isolated from the wood of medicinal plant Cinnamomum species, resulted in the isolation of one new furanoid derivative, ilanefuranone (1), one new pyrrole alkaloid, ilanepyrrolal (2), and one new biarylpropanoid derivative, ilanenoid (3), together with 22 known compounds, of which one α-tetralone analog, (-)-(4R)-3,4-dihydro-4,6-dihydroxynaphthalen-1(2H)-one (4) was isolated for the first time from a natural source. The structures were elucidated on the basis of physicochemical evidence, in-depth NMR spectroscopic analysis, and high-resolution mass spectrometry, and the antimycobacterial activities were also evaluated.