Abstract: The present invention relates to a modified bacterium with anti-tumor activity, which comprises an essential gene expression cassette under the control of a strictly hypoxia inducible promoter and is deficient in at least one gene involved in or regulating the endogenous anti-oxidative stress response pathway or a functional expression product thereof. The present invention also relates to a pharmaceutical composition comprising the modified bacterium and anti-tumor use thereof.

Abstract: A visual continuous spatial directed evolution method is disclosed. The host grows and moves in a solid culture space, the host carrying a foreign target gene to be evolved and containing a gene element that assists the evolution of the target gene, the target gene being correlated with the growth and movement of the host. Depending on different spatial distribution patterns formed in the solid culture space during the growth and movement of the host, screening is performed to obtain an evolved product. This method is carried out directly in the solid culture space. Depending on images of different spatial distribution morphologies visible to the naked eye that are locally formed, selection of evolved products is performed without the need for liquid fed-batch culture equipment. In addition, the evolution effect is visually observed through the infection spots formed during evolution, so that no real-time monitoring equipment is required.

Abstract: A bacterial targeting vector and use thereof in tumor treatment, in particular, a bacterial targeting vector carrying a cytokine such as interleukin 6 and interleukin 10 or carrying a polynucleotide such as mRNA of the cytokine and use thereof in tumor treatment. An attenuated chassis bacterium capable of targeting solid tumors can be used as a delivery carrier of a tumor therapy molecule, and achieve expression and controllable release of a human/murine cytokine, thereby achieving anti-tumor effects.

Abstract: The invention relates to a method for constructing an obligate anaerobic Salmonella strain, the obligate anaerobic Salmonella strain constructed by using said method, and the use thereof in tumor therapy.

Abstract: A visual continuous spatial directed evolution method is disclosed. The host grows and moves in a solid culture space, the host carrying a foreign target gene to be evolved and containing a gene element that assists the evolution of the target gene, the target gene being correlated with the growth and movement of the host. Depending on different spatial distribution patterns formed in the solid culture space during the growth and movement of the host, screening is performed to obtain an evolved product. This method is carried out directly in the solid culture space. Depending on images of different spatial distribution morphologies visible to the naked eye that are locally formed, selection of evolved products is performed without the need for liquid fed-batch culture equipment. In addition, the evolution effect is visually observed through the infection spots formed during evolution, so that no real-time monitoring equipment is required.

Abstract: A visual continuous spatial directed evolution method is disclosed. The host grows and moves in a solid culture space, the host carrying a foreign target gene to be evolved and containing a gene element that assists the evolution of the target gene, the target gene being correlated with the growth and movement of the host. Depending on different spatial distribution patterns formed in the solid culture space during the growth and movement of the host, screening is performed to obtain an evolved product. This method is carried out directly in the solid culture space. Depending on images of different spatial distribution morphologies visible to the naked eye that are locally formed, selection of evolved products is performed without the need for liquid fed-batch culture equipment. In addition, the evolution effect is visually observed through the infection spots formed during evolution, so that no real-time monitoring equipment is required.