Engineering a heterologous synthetic pathway in Escherichia coli for efficient production of biotin.

OBJECTIVE: To enhance biotin production in Escherichia coli by engineering a heterologous biotin synthetic pathway. RESULTS: Biotin operon genes from Pseudomonas putida, which consisted of a bioBFHCD cluster and a bioA gene, was engineered into Escherichia coli for biotin production. The introduction of bioW gene from Bacillus subtilis, encoding pimeloyl-CoA synthetase and sam2 gene from Saccharomyces cerevisiae, encoding S-adenosyl-L-methionine (SAM) synthetase contributed to the heterologous production of biotin in recombinant E. coli. Furthermore, biotin production was efficiently enhanced by optimization of the fermentation compositions, especially pimelic acid and L-methionine, the precursor related to the pimeloyl-CoA and SAM synthesis, respectively. The combination of overexpression of the heterologous biotin operon genes and enhanced supply of key intermediate pimeloyl-CoA and SAM increased biotin production in E. coli by more than 121-fold. With bioprocess engineering efforts, biotin was produced at a final titer of 92.6 mg/L in a shake flask and 208.7 mg/L in a fed-batch fermenter. CONCLUSION: Through introduction of heterologous biotin synthetic pathway, increasing the supply of precursor pimeloyl-CoA and cofactor SAM can significantly enhance biotin production in E. coli.

Identification of Prognostic Related Hub Genes in Clear-Cell Renal Cell Carcinoma via Bioinformatical Analysis.

Objective To identify new genes that correlate with prognosis of clear-cell renal cell carcinoma (ccRCC) via bioinformatics analysis. Methods The gene expression profiles of 62 ccRCC and 54 normal kidney tissues were available from the Gene Expression Omnibus database: GSE12606, GSE36895 and GSE66272. The differentially expressed genes were screened with GEO2R and J Venn online tools. Functional annotation including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) was applied to identify the possible function of the hub genes involved in prognosis of ccRCC. In protein protein interaction network (PPI network), the STRING online tool was used to visualize the network of the differentially expressed genes, and the core gene was selected by MCODE App in Cytoscape software. Finally, GEPIA Survival Plot was performed to assess genes associated with worse survival. Results We totally found 648 differentially expressed genes, including 222 up-regulated genes and 426 down-regulated genes. PPI network showed that in 28 up-regulated genes 7 (CCNE2, CDK1, CDC6, CCNB2, BUB1, TTK and PTTG1) enriched in cell cycle and 4 genes (CCNE2, CDK1, CCNB2 and RRM2) enriched in p53 signaling pathway. GEPIA Survival Plot assay revealed that ccRCC patients carrying CDK1, CCNB2, RRM2, BUB1, and PTTG1 had a worse survival. GEPIA Box Plot showed that BUB1, CCNB2, PTTG1, and RRM2 were over expressed in the ccRCC tissues in contrast to the normal tissues (P<0.05). Conclusion ccRCC patients with the four up-regulated differentially expressed genes including BUB1,CCNB2,PTTG1, and RRM2might manifest a poor prognosis.

[Regulatory effect of Jinkui Shenqi Pills on the gene expression of the Nrf2 signaling pathway in cyclophosphamide-induced testis injury in mice].

OBJECTIVE: To investigate the protective effect of Jinkui Shenqi Pills (JSP) against cyclophosphamide-induced testis injury (TI) and its anti-oxidation mechanism in mice. METHODS: Thirty male mice were equally divided into a blank control, a TI model control and a JSP treatment group. The mice in the JSP treatment group were treated intragastrically with JSP and the blank controls with normal saline at 1.2 g/kg qd for 7 days, and then the animals in both the TI model control and JSP treatment groups were injected intraperitoneally with cyclophosphamide at 50 mg/kg, once a week, for 35 days, to induce testis injury. After modeling, all the mice were weighed and sacrificed, followed by detection of the serum T content, measurement of the testis weight, examination of semen parameters in the caudad epididymis, and determination of the levels of super oxide dismutase (SOD) and malondialdehyde (MDA) in the testis tissue and the expressions of relevant genes by qRT-PCR. RESULTS: The mice of the TI model control group, compared with the blank controls, showed significant decreases in the body weight (ï¼»34.63 ± 1.92ï¼½ vs ï¼»48.32 ± 1.64ï¼½ g, P<0.05), testis weight (ï¼»80.00 ± 3.90ï¼½ vs ï¼»140.00 ± 6.10ï¼½ mg, P<0.05), testicular organ coefficient (ï¼»0.22 ± 0.01ï¼½ vs ï¼»0.31 ±0.03ï¼½%, P<0.05), sperm motility (ï¼»48.66 ± 8.08ï¼½% vs ï¼»89.33 ± 4.04ï¼½%, P<0.05), sperm concentration (ï¼»28.42 ± 5.26ï¼½ vs ï¼»77.67 ± 8.73ï¼½ ×106/ml, P<0.05), and levels of serum T (ï¼»8.75 ± 0.96ï¼½ vs ï¼»21.75 ± 1.71ï¼½ pg/ml, P<0.05) and SOD (ï¼»140.82 ± 10.08ï¼½ vs ï¼»358.52 ± 40.41ï¼½ U/mg prot, P<0.05), but remarkable increases in the sperm deformity rate (ï¼»37.33 ± 2.08ï¼½ vs ï¼»15.33±1.53ï¼½%, P<0.05) and MDA level (ï¼»54.89±6.09ï¼½ vs ï¼»30.21±2.17ï¼½ nmol/ng prot, P<0.05). The mice of the JSP treatment group, in comparison with the TI model controls, exhibited markedly increased body weight (ï¼»39.80±2.89ï¼½ vs ï¼»34.63±1.92ï¼½g, P<0.05), testis weight (ï¼»130.00 ± 11.00ï¼½ vs ï¼»80.00 ± 3.90ï¼½ mg, P<0.05), testicular organ coefficient (ï¼»0.28 ± 0.01ï¼½ vs ï¼»0.22 ± 0.01ï¼½%, P<0.05), sperm motility (ï¼»76.00 ± 5.29ï¼½% vs ï¼»48.66 ± 8.08ï¼½%, P<0.05), sperm concentration (ï¼»56.08 ± 4.29ï¼½ vs ï¼»28.42 ± 5.26ï¼½ ×106/ml, P<0.05), and levels of serum T (ï¼»15.50 ± 1.29ï¼½ vs ï¼»8.75 ± 0.96ï¼½ pg/ml, P<0.05) and SOD (ï¼»206.59 ± 16.38ï¼½ vs ï¼»140.82 ± 10.08ï¼½ U/mg prot, P<0.05), but decreased sperm deformity rate (ï¼»25.01 ± 2.99ï¼½% vs ï¼»37.33 ± 2.08ï¼½%, P<0.05) and MDA level (ï¼»35.84 ± 3.61ï¼½ vs ï¼»54.89 ± 6.09ï¼½ nmol/ng prot, P<0.05). The mRNA expressions of NOQ-1, Nrf2 and HO-1 in the testis tissue were significantly lower and that of Caspase-3 remarkably higher in the TI model control than in the blank control group (P<0.05), while those of Nrf2 and HO-1 significantly higher and that of Caspase-3 markedly lower in the JSP treatment group than in the TI model controls (P<0.05). Histopathological images displayed reduced layers of spermatogenic cells in the seminiferous tubules, complete exfoliation of the spermatogenic cells in some of the tubules and decreased number of sperm cells in the TI model controls, which were all found normal in the JSP treatment group. CONCLUSIONS: Jinkui Shenqi Pills can effectively inhibit cyclophosphamide-induced testis injury, which may be related to its effect of regulating the gene expression of the Nrf2 signaling pathway and enhancing the activity of antioxidant enzymes.

[Diversity and difference of endophytes in Dendrobium huoshanense with different growth years].

In order to explore endophytes diversity and difference in Dendrobium huoshanense,in this paper,the metagenomics method was used to analyze the endophytic bacteria and fungi community of 5 groups include 30 samples in different growth years. The results indicate that 3 540 bacterial OTUs were identified from D. huoshanense,and there are 138 OTUs in 5 groups simultaneously;2 168 fungal OTUs were identified,and 143 OTUs exist in 5 groups simultaneously. The dominate endophytic bacteria community are Sphingomonas sp.,Acinetobacter sp.,Burkholderia sp.,Methylobacterium sp.,Enterococcus sp.,Bacillus sp.,the difference endophytic bacteria community are Oceanobacillusd sp.,Actinomycetospora sp.,Paenibacillus sp.. The dominate endophytic fungi community are Zasmidium sp.,Zymoseptoria sp.,Alternaria sp.,Cladosporium sp.,Fusarium sp.,the difference endophytic fungi community are Cyphellophore sp.,Fusarium sp.. The results of clustering revealed that both the endophytic bacteria and the endophytic fungi,ⅢY2 and ⅢY3 are complete clustered,and ⅡY1 and ⅢY1 are also cluster completely. These enriched the species and resources of endophytic bacteria and fungi in D. huoshanense,and provided a theoretical reference for the reasonable harvest of D. huoshanense.

Gilteritinib Enhances Anti-Tumor Efficacy of CDK4/6 Inhibitor, Abemaciclib in Lung Cancer Cells.

Abemaciclib is a cyclin-dependent kinases 4/6 (CDK4/6) inhibitor approved for the treatment of metastatic breast cancer. Preclinical studies suggest that abemaciclib has the potential for lung cancer treatment. However, several clinical trials demonstrate that monotherapy with abemaciclib has no obvious superiority than erlotinib to treat lung cancer patients, limiting its therapeutic options for lung cancer treatment. Here, we show that the US Food and Drug Administration (FDA)-approved drug, gilteritinib, enhances the cytotoxicity of abemaciclib through inducing apoptosis and senescence in lung cancer cells. Interestingly, abemaciclib in combination with gilteritinib leads to excessive accumulation of vacuoles in lung cancer cells. Mechanistically, combined abemaciclib and gilteritinib induces complete inactivation of AKT and retinoblastoma (Rb) pathways in lung cancer cells. In addition, RNA-sequencing data demonstrate that combination of abemaciclib and gilteritinib treatment induces G2 phase cell-cycle arrest, inhibits DNA replication, and leads to reduction in homologous recombination associated gene expressions. Of note, abemaciclib-resistant lung cancer cells are more sensitive to gilteritinib treatment. In a mouse xenograft model, combined abemaciclib and gilteritinib is more effective than either drug alone in suppressing tumor growth and appears to be well tolerated. Together, our findings support the combination of abemaciclib with gilteritinib as an effective strategy for the treatment of lung cancer, suggesting further evaluation of their efficacy is needed in a clinical trial.

Targeting Gut Microbiota With Natural Polysaccharides: Effective Interventions Against High-Fat Diet-Induced Metabolic Diseases.

Unhealthy diet, in particular high-fat diet (HFD) intake, can cause the development of several metabolic disorders, including obesity, hyperlipidemia, type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), and metabolic syndrome (MetS). These popular metabolic diseases reduce the quality of life, and induce premature death worldwide. Evidence is accumulating that the gut microbiota is inextricably associated with HFD-induced metabolic disorders, and dietary intervention of gut microbiota is an effective therapeutic strategy for these metabolic dysfunctions. Polysaccharides are polymeric carbohydrate macromolecules and sources of fermentable dietary fiber that exhibit biological activities in the prevention and treatment of HFD-induced metabolic diseases. Of note, natural polysaccharides are among the most potent modulators of the gut microbiota composition. However, the prebiotics-like effects of polysaccharides in treating HFD-induced metabolic diseases remain elusive. In this review, we introduce the critical role of gut microbiota human health and HFD-induced metabolic disorders. Importantly, we review current knowledge about the role of natural polysaccharides in improving HFD-induced metabolic diseases by regulating gut microbiota.

The role of Insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) as m6A readers in cancer.

RNA can be modified by over 170 types of distinct chemical modifications, and the most abundant internal modification of mRNA in eukaryotes is N6-methyladenosine (m6A). The m6A modification accelerates mRNA process, including mRNA splicing, translation, transcript stability, export and decay. m6A RNA modification is installed by methyltransferase-like proteins (writers), and potentially removed by demethylases (erasers), and this process is recognized by m6A-binding proteins (readers). Notably, alterations of m6A-modified proteins (writers, erasers and readers) are involved in the tumorigenesis, progression and metastasis. Importantly, the fate of m6A-methylated mRNA is mediated mostly through m6A readers, and among these readers, insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) are unique RNA-binding proteins (RBPs) that stabilize their targets mRNA via m6A modification. In this review, we update the writers, erasers and readers, and their cross-talks in m6A modification, and briefly discuss the oncogenic role of IGF2BPs in cancer. Most importantly, we mainly review the up-to-date knowledges of IGF2BPs (IGF2BP1/2/3) as m6A readers in an m6A-modified manner in cancer progression.

Rapid quantification of polysaccharide and the main onosaccharides in Dendrobium huoshanense by near-infrared attenuated total reflectance spectroscopy.

A rapid, green, low cost and nondestructive attenuated total reflection near infrared (ATR NIR) method was developed to quantify the total polysaccharide and the main monosaccharides mannose and glucose in Dendrobium huoshanense. Total 100 D. huoshanense samples from different places were analyzed using ATR NIR method. Potential outlying samples were initially removed from the collected NIR data using the PCA-Mahalanobis distance method. Spectral data preprocessing was studied in the construction of a partial least squares (PLS) model and six different signal pretreatment methods, including multiplicative scattering correction (MSC), standard normal transformation (SNV), first and second derivatives, the combination of MSC with the first derivative, and the combination of SNV with the first derivative, were compared. The results showed that the best signal pretreatment method was the spectral data pretreated by SNV combined with the first derivative due to it showed the lowest root-mean-square error of cross-validation (RMSECV), highest R2 for both the polysaccharide and its main monosaccharides. In order to improve the performance of the model, the pretreated full spectrum was calculated by different wavelength selection method. The results showed that the optional wavelength selection model was the one simultaneously selecting the NIR wavelength ranges 7500-5750 cm-1, 5250-4700 cm-1, 4450-4300 cm-1 and 4200-4100 cm-1 because of the lowest RMSECV and the highest R2 among the ten wavelength selection models. The external validation and the complete external validation confirmed the robustness and reliability of the developed NIR model. The contents of the total polysaccharide and the main monosaccharides are the essential quality assessment criterion for plant medicines while their traditional quantification methods involved sample destruction, tedious sample processing and non-environmentally friendly pretreatment, therefore, our study might provide an efficient technique tool for the rapid, green and nondestructive quantification of the total polysaccharide and the main monosaccharides for D. huoshanense and other rich-in-polysaccharide plant medicines.

Separation and structure elucidation of a new homoflavanol derivative from Pteridium aquilinum (L.) Kuhn.

A novel homoflavanol derivative (1) with an unprecedented skeleton, as well as two known flavonoids kaempferol (2) and quercetin (3), was isolated from the plant Pteridium aquilinum (L.) Kuhn, and the structure and relative stereochemistry of the new compound (1) were elucidated on the basis of spectroscopic data.

Rapid identification of three varieties of Chrysanthemum with near infrared spectroscopy

A total of 139 batches of Chrysanthemum samples were randomly divided into calibration set (92 batches) and prediction set (47 batches). The near infrared diffuses reflectance spectra of Chrysanthemum varieties were preprocessed by a first order derivative (D1) and autoscaling, and a modelwas built using partial least squares analysis. In this study, three Chrysanthemum varieties were identified, the accuracy rates in calibration sets of Dabaiju, Huju, and Xiaobaiju are 97.60, 96.65, and 94.70%, respectively; And 95.16, 86.11, and 93.46% accuracy rate in prediction sets was obtained. The research results demonstrate that the qualitative analysis can be conducted by machine learning combined with Near-Infrared Spectroscopy, which provides a new method for rapid and non-invasive identification of Chrysanthemum varieties.