Engineering yeasts to Co-utilize methanol or formate coupled with CO2 fixation.

The development of synthetic microorganisms that could use one-carbon compounds, such as carbon dioxide, methanol, or formate, has received considerable interest. In this study, we engineered Pichia pastoris and Saccharomyces cerevisiae to both synthetic methylotrophy and formatotrophy, enabling them to co-utilize methanol or formate with CO2 fixation through a synthetic C1-compound assimilation pathway (MFORG pathway). This pathway consisted of a methanol-formate oxidation module and the reductive glycine pathway. We first assembled the MFORG pathway in P. pastoris using endogenous enzymes, followed by blocking the native methanol assimilation pathway, modularly engineering genes of MFORG pathway, and compartmentalizing the methanol oxidation module. These modifications successfully enabled the methylotrophic yeast P. pastoris to utilize both methanol and formate. We then introduced the MFORG pathway from P. pastoris into the model yeast S. cerevisiae, establishing the synthetic methylotrophy and formatotrophy in this organism. The resulting strain could also successfully utilize both methanol and formate with consumption rates of 20 mg/L/h and 36.5 mg/L/h, respectively. The ability of the engineered P. pastoris and S. cerevisiae to co-assimilate CO2 with methanol or formate through the MFORG pathway was also confirmed by 13C-tracer analysis. Finally, production of 5-aminolevulinic acid and lactic acid by co-assimilating methanol and CO2 was demonstrated in the engineered P. pastoris and S. cerevisiae. This work indicates the potential of the MFORG pathway in developing different hosts to use various one-carbon compounds for chemical production.

Doramectin inhibits glioblastoma cell survival via regulation of autophagy in vitro and in vivo.

Glioblastoma (GBM) is one of the most widespread and lethal types of cancer. However, there are currently no drugs or therapeutic strategies that can completely cure GBM. Doramectin (DRM) has a broad range of activities against endoparasites and ectoparasites, and is extensively used in livestock. In the present study, the effect of DRM on the induction of autophagy in U87 and C6 GBM and glioma cell lines, as well as the mechanism of autophagy, were examined. First, transmission electron microscopy, plasmid transfection and western blot analysis demonstrated that DRM could induce autophagy in U87 and C6 cells in vitro. Next, MTT and colony formation assays revealed that DRM­induced autophagy prevented U87 and C6 cell viability and colony formation ratio. In addition, DRM­induced autophagy promoted U87 and C6 cell apoptosis, as indicated by DAPI analysis and flow cytometry. Furthermore, transcriptome analysis demonstrated that DRM modulated a number of genes and pathways involved in autophagy. In a nude mouse xenograft model, immunohistochemical staining and the TUNEL assay demonstrated that the effect of DRM on the tumor was consistent with that in vivo. These data indicated that DRM induced autophagy mainly by blocking the PI3K/AKT/mTOR signaling pathway in GBM cells. DRM­induced autophagy promoted the inhibition of GBM cell proliferation and apoptosis in vitro and in vivo. The present study suggested that DRM may be an effective drug for the treatment of GBM.

2,3,5,6-Tetra-fluoro-1,4-bis-({[(thio-phen-2-yl)methyl-idene]amino}-meth-yl)benzene.

In the title compound, C18H12F4N2S2, a bis-thio-phenyl Schiff base ligand with a perifluorinated aromatic core, the complete molecule is generated by crystallographic inversion symmetry. The thio-phene and tetra-fluorinated benzene rings are oriented at a dihedral angle of 77.38 (4)°. The crystal structure exhibits C-H⋯F hydrogen bonds, resulting in supra-molecular chains along the c-axis direction.

2,3,5,6-Tetra-fluoro-1,4-bis-({[(5-methyl-thio-phen-2-yl)methyl-idene]amino}-meth-yl)benzene.

The title compound, C20H16F4N2S2, is a flexible bis-thio-phene-type Schiff base ligand with a perfluorinated backbone. The terminal thio-phene rings are almost normal to one another with a dihedral angle of 83.8 (2)°, and they are tilted to the central tetra-fluorinated benzene ring with dihedral angles of 61.2 (2) and 77.7 (1)°. In the crystal, there are π-π inter-actions involving the benzene ring and the thiophene ring of a symmetry-related molecule with a centroid-centroid separation of 3.699 (3) Å.