Main conclusionWe assembled the complete mitochondrial genome of Scutellaria tsinyunensis in this study. Repeatmediated recombination resulted in the formation of two conformations of the mitochondrial genome in S. tsinyunensis.

In photodynamic therapy (PDT), elevated reactive oxygen species (ROS) activate tumor cell protective autophagy, therefore attenuating the antitumor function of therapy. Hence, inhibition of protective autophagy in tumors can improve the antitumor effect of PDT. Herein, an innovative nanotraditional Chinese medicine system ((TP+A)@TkPEG NPs), which remodeled autophagy homeostasis, was fabricated. A photosensitizer aggregation inducing emission (AIE) and autophagy modulator triptolide (TP, an active ingredient of Tripterygium wilfordii Hook F) were encapsulated into ROS-responsive nanoparticles to improve antitumor effect of PDT in treatment of triple negative breast cancer. We proved that (TP+A)@TkPEG NPs effectively elevated intracellular ROS levels, activated ROS-responsive release of TP and inhibited the proliferation of 4T1 cells in vitro. More importantly, it sharply reduced autophagy related genes transcription and proteins expression in 4T1 cells, then promote cell apoptosis. In addition, this nanoherb therapeutic system effectively orientated to tumor sites, achieved efficient inhibition of tumor, and extended the survival time of 4T1-bearing mice in vivo. Further results confirmed that (TP+A)@TkPEG NPs remarkably inhibit the expression level of autophagy related initiation gene (becline-1) and elongation protein (light chain 3B) in tumor microenvironment and then block PDT induced protective autophagy. In brief, this system can remodel autophagy homeostasis and serve as an innovative approach for treatment of triple negative breast cancer.

Scutellaria Linn. is a perennial herb with about 300 species. This genus has high medicinal value and many are used in Traditional Chinese Medicine (TCM). In this study, we sequenced and assembled the complete chloroplast genomes of Scutellaria tsinyunensis and S. tuberifera . Subsequently, we conducted a comprehensive comparative genomics analysis with 12 other published Scutellaria species. These genomes all had a conserved quartile structure, and the gene contents, gene sequences and GC contents are highly similar. The study on the genetic characteristics and nucleotide substitution rate of different genes found that the protein-coding genes of chloroplasts have differed greatly. Most genes are under purifying selection, but the rps 12 gene may have undergone positive selection. Besides, we identified three hypervariable regions as potential markers for Scutellaria taxa, which could play an important role in species identification of Scutellaria . Phylogenetic analysis showed that the 14 Scutellaria taxa were divided into two major clades. Moreover, the variation of IR regions is closely related to the evolutionary history as was reconstructed based on SNPs. In conclusion, we provided two high-quality chloroplast reference genomes of Scutellaria , this reliable information and genomic resources are valuable for developing of efficient DNA barcodes as reconstruction of chloroplast evolutionary history of the genus.

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Staphylococcus aureus is one of the major foodborne pathogens and can cause serious foodborne illness in humans by foods contaminated with S. aureus enterotoxins. In recent years, livestock-associated S. aureus has been a major public health concern for humans and has emerged in various countries globally. China is one of the largest producers of pigs and pork in the world. However, there are few studies on the detailed genotypic and pathogenic characterization of pork-associated S. aureus in China. In this study, the prevalence, antimicrobial resistance, and genotypic characteristics of S. aureus in raw pork in Wuhan, China, were investigated through multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and whole-genome sequencing analysis. A total of 518 S. aureus isolates (16.9%) were isolated from 3067 retail and wholesale pork samples. The prevalence of S. aureus in retail pork (22.7%) was significantly higher than in wholesale pork (15.1%), while the proportion of multidrug-resistant (MDR) isolates in wholesale pork (12.9%) was significantly higher than in retail pork (6.2%). Among the isolates, 10.8% were resistant to three or more antibiotics, with higher rates of resistance to penicillin (88.8%) and erythromycin (58.1%). A total of 28 sequence types (STs) were identified in the 518 isolates, and the predominant type was ST7 (57.5%), followed by ST5 (9.1%). In addition, based on the whole-genome sequences of 39 representative strains, 17 spa types were identified among the isolates, of which t899, t091, and t437 were the most common. Furthermore, 19 staphylococcal enterotoxin (SE) and SE-like (SEl) toxin genes were detected in the isolates, of which selw was the most common type (100%), followed by sei, sem, seo, seu, and selv (46.2%); sey (35.9%); and sea, seg, and sen (33.3%). This study found for the first time that ST7-t091-selw and ST9-t899-SCCmecXII-selw were the predominant genotypes of S. aureus in pork in China, which indicated the spreading of S. aureus with multiple virulence factors, especially with new SE/SEl types in pigs and pork, is a serious new challenge for food safety. Good hygiene and good production practices to prevent interspecies transmission and cross-contamination of S. aureus in the pig–pork chain are of great significance to public health.