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To compare the allergenicity of native arginine kinase (nAK) and recombinant AK (rAK) from Scylla paramamosain and to identify the predominant allergenic domain of AK, AK was divided into 4 fragments: AK-E1 (amino acid (AA) 1–92), AK-E2 (AA 87–187), AK-E3 (AA 172–265), and AK-E4 (AA 276–357) based on the distribution of epitopes and the spatial structure of the AK molecule. The four recombinant fragments were expressed in the prokaryotic system Escherichia coli, and then nAK, rAK, and the recombinant fragments were purified. The allergenicity of recombinant proteins were evaluated using BALB/c mice. The results showed that the levels of specific antibodies in the serum and the secretion of Th2 type cytokines by the splenocytes of mice sensitized with rAK significantly increased, but the immunogenicity of rAK was weaker than that of nAK. Among the 4 fragments of AK, AK-E2 had the strongest immunogenicity. Meanwhile, rAK could stimulate RBL-2H3 cells to release β-hexokinase, but it was less effective than nAK. Among the 4 expressed fragments, AK-E2 and AK-E4 had a stronger stimulating effect on effector cells. In conclusion, the rAK expressed in the prokaryotic system showed weaker immunogenicity than nAK, and among the 4 fragments of AK, AA 87–187 has the strongest immunogenicity while AA 276–357 has the strongest immunoreactivity.

Bacteria‐initiated cancer therapy has been demonstrated high therapeutic efficacy against cancer. However, the undesired therapeutic efficacy and induced systematic inflammation storm compromise the therapeutic effect and outcome. Herein, a thermally‐activated living nanomedicine composed of reactive biohybrid (designated as Sa@FeS) is rationally designed and engineered for enhancing hydrogen sulfide (H2S)‐combined chemodynamic oncotherapy by biomineralizing ferrous sulfide nanoparticles (FeS NPs) onto the surface of a Salmonella typhimurium strain (Sa) without reducing bacterial activity. Ascribed to the deep penetration capability of Sa, FeS NPs facilitate photothermally‐enhanced catalytic Fenton reaction of decomposing endogenous H2O2 into cytotoxic hydroxyl radicals deep in tumor tissues upon near infrared irradiation. Meanwhile, Sa bacteria maintain sustained H2S release within tumor for achieving H2S‐induced intracellular acidosis that favors the generation of reactive oxygen species synergistically. Of note, the thermally‐triggered all‐in‐one strategy effectively inhibits bacterial viability, thus reducing the risk of systematic inflammation storm and ensuring biosafety. Therefore, the engineered nano‐bacteria living system exerts the thermally‐enhanced nanocatalytic and gas therapies to effectively eradicate tumors, providing a distinct paradigm for the combination of synthetic biology and nanomedicine in tumor therapy. [ABSTRACT FROM AUTHOR]

Trichosanthes kirilowii (T. kirilowii) is a valuable plant used for both medicinal and edible purposes. It belongs to the Cucurbitaceae family. However, its phylogenetic position and relatives have been difficult to accurately determine due to the lack of mitochondrial genomic information. This limitation has been an obstacle to the potential applications of T. kirilowii in various fields. To address this issue, Illumina and Nanopore HiFi sequencing were used to assemble the mitogenome of T. kirilowii into two circular molecules with sizes of 245,700 bp and 107,049 bp, forming a unique multi-branched structure. The mitogenome contains 61 genes, including 38 protein-coding genes (PCGs), 20 tRNAs, and three rRNAs. Within the 38 PCGs of the T. kirilowii mitochondrial genome, 518 potential RNA editing sites were identified. The study also revealed the presence of 15 homologous fragments that span both the chloroplast and mitochondrial genomes. The phylogenetic analysis strongly supports that T. kirilowii belongs to the Cucurbitaceae family and is closely related to Luffa. Collinearity analysis of five Cucurbitaceae mitogenomes shows a high degree of structural variability. Interestingly, four genes, namely atp1, ccmFC, ccmFN, and matR, played significant roles in the evolution of T. kirilowii through selection pressure analysis. The comparative analysis of the T. kirilowii mitogenome not only sheds light on its functional and structural features but also provides essential information for genetic studies of the genus of Cucurbitaceae. [ABSTRACT FROM AUTHOR]