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Research on the roles of the bacteria in tumor development and progression is a rapidly emerging field. Increasing evidence links bacteria with the modification of the tumor immune microenvironment, which greatly influences the antitumor response. In view of the individual immune effects of various bacteria in various tumors, developing personalized bacteria-modulating therapy may be a key to successful antitumor treatment. This review emphasizes the critical role of the bacteria in immune regulation, including both the tumor bacteria and gut bacteria. Aiming at tumor-related bacteria, we focus on various precise modulation strategies and discuss their impact and potential for tumor suppression. Finally, engineered bacteria with tumor-targeting ability could achieve precise delivery of various payloads into tumors, acting as a precision tool. Therefore, a precise tumor-related bacteria therapy may be a promising approach to suppress the development of tumors, as well as an adjuvant therapy to improve the antitumor efficacy of other approaches. KEY POINTS: • The mini-review updates the knowledge on complex effect of bacteria in TME. • Insight into the interaction and adjustment of bacteria in gut for TME. • Prospects and limitations of bacteria-related personalized therapy in the clinical anticancer therapy.

A novel actinomycete strain, designated S2-4

Oscillospira is a class of organism that often appears in high-throughput sequencing data but has not been purely cultured and is widely present in the animal and human intestines. There is a strong association between variation in Oscillospira abundance and obesity, leanness, and human health. In addition, a growing body of studies has shown that Oscillospira is also implicated in other diseases, such as gallstones and chronic constipation, and has shown some correlation with the positive or negative changes in its course. Sequencing data combined with metabolic profiling indicate that Oscillospira is likely to be a genus capable of producing short-chain fatty acids (SCFAs) such as butyrate, which is an important reference indicator for screening “next-generation probiotics “. Considering the positive effects of Oscillospira in some specific diseases, such as obesity-related metabolic diseases, it has already been characterized as one of the next-generation probiotic candidates and therefore has great potential for development and application in the future food, health care, and biopharmaceutical products.

A Gram-negative bacterium, designated S1-65T, was isolated from soil samples collected from a cotton field located in the Xinjiang region of PR China. Results of 16S rRNA gene sequence analysis revealed that strain S1-65T was affiliated to the genus Steroidobacter with its closest phylogenetic relatives being ‘Steroidobacter cummioxidans’ 35Y (98.4 %), ‘ Steroidobacter agaridevorans ’ SA29-B (98.3 %) and Steroidobacter agariperforans KA5-BT (98.3 %). 16S rRNA-directed phylogenetic analysis showed that strain S1-65T formed a unique phylogenetic subclade next to ‘ S. agaridevorans ’ SA29-B and S. agariperforans KA5-BT, suggesting that strain S1-65T should be identified as a member of the genus Steroidobacter . Further, substantial differences between the genotypic properties of strain S1-65T and the members of the genus Steroidobacter , including average nucleotide identity and digital DNA–DNA hybridization, resolved the taxonomic position of strain S1-65T and suggested its positioning as representing a novel species of the genus Steroidobacter . The DNA G+C content of strain S1-65T was 62.5 mol%, based on its draft genome sequence. The predominant respiratory quinone was ubiquinone-8. The main fatty acids were identified as summed feature 3 (C16:1ω6c/C16:1ω7c), C16 : 0 and iso-C15 : 0. In addition, its polar lipid profile was composed of aminophospholipid, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. Here, we propose a novel species of the genus Steroidobacter : Steroidobacter gossypii sp. nov. with the type strain S1-65T (=JCM 34287T=CGMCC 1.18736T).

A Gram-positive, acid-fast and rapidly growing rod, designated S2-37 T , that could form yellowish colonies was isolated from soil samples collected from cotton cropping field located in the Xinjiang region of China. The draft genome of strain S2-37 T was 5.1 Mb in length, with a DNA G+C content of 68.4 mol%. 16S rRNA-directed phylogenetic analysis referred that strain S2-37 T was closely related to bacterial species belonging to the genus Mycolicibacterium and Mycobacterium . Multilocus sequence analysis of three genes (16S rRNA, hsp65 and rpoB ) revealed that strain S2-37 T shared high sequence similarities with Mycolicibacterium litorale CGMCC 4.5724 T (96.5%) and Mycobacterium neglectum CECT 8778 T (95.7%). Digital DNA-DNA hybridization (dDDH) and the average nucleotide identity (ANI) presented that strainS2-37 T displayed the highest values of 39.1% (35.7-42.6%) and 81.28% with M. litorale CGMCC 4.5724 T , respectively. And characterazition of conserved molecular signatures further confirmed that strain S2-37 T could be well classified into the genus Mycolicibacterium . The main fatty acids were identified as C 16:0 , C 18:0 , C 20:3 ω3 and C 22:6 ω3 . In addition, polar lipids profile was mainly composed of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Results indicated that strain S2-37 T represented genetically and phenotypically distinct from its closest phylogenetic neighbour, M. litorale CGMCC 4.5724 T . Here, we propose a novel species of the genus Mycolicibacterium : Mycolicibacterium gossypii sp. nov. with the type strain S2-37 T (=JCM 34327T =CGMCC 1.18817T ).

As fungus-like protists, thraustochytrids have been increasingly studied for their faster growth rates and high lipid content. In the 1990s, thraustochytrids were used as docosahexaenoic acid (DHA) producers for the first time. Thraustochytrids genera, such as Thraustochytrium, Schizochytrium, and Aurantiochytrium have been developed and patented as industrial strains for DHA production. The high DHA yield is attributed to its unique and efficient polyketide-like synthase (PKS) pathway. Moreover, thraustochytrids possess a completed mevalonate (MVA) pathway, so it can be used as host for terpenoid production. In order to improve strain performance, the metabolic engineering strategies have been applied to promote or disrupt intracellular metabolic pathways, such as genetic engineering and addition of chemical activators. However, it is difficult to realize industrialization only by improving strain performance. Various operation strategies were developed to enlarge the production quantities from the laboratory-scale, including two-stage cultivation strategies, scale-up technologies and bioreactor design. Moreover, an economical and effective downstream process is also an important consideration for the industrial application of thraustochytrids. Downstream costs accounts for 20-60% of the overall process costs, which represents an attractive target for increasing the cost-competitiveness of thraustochytrids, including how to improve the efficiency of lipid extraction and the further application of biomass residues. This review aims to overview the whole lipid biotechnology of thraustochytrids to provide the background information for researchers.

Great efforts have been made to the investigation of defects in silicon carbide for their attractive optical and spin properties. However, most of the researches are implemented at low and room temperature. Little is known about the spin coherent property at high temperature. Here, we experimentally demonstrate coherent control of divacancy defect spins in silicon carbide above 550 K. The spin properties of defects ranging from room temperature to 600 K are investigated, in which the zero-field-splitting is found to have a polynomial temperature dependence and the spin coherence time decreases as the temperature increases. Moreover, as an example of application, we demonstrate a thermal sensing using the Ramsey method at about 450 K. Our experimental results would be useful for the investigation of high temperature properties of defect spins and silicon carbide-based broad-temperature range quantum sensing., Comment: 5 pages, 5 figures

Elasticity variations in railway overhead contact line would lead to the fluctuation of contact force between pantograph and contact wire and produce a negative effect on the stability of current collection. Dropper distribution is one of the key factors affecting the elasticity of the contact wire. In this paper, the influence of dropper spacing on elasticity and quality of current collection have been studied using finite element analysis method by simulation. By analyzing the changes of elasticity value and contact force under different conditions of dropper distribution, the effect laws of dropper spacing on the contact wire elasticity and the quality of current collection under the speeds of 300km/h, 350km/h and 400km/h have been obtained.

The recent experimental progress in parity-time (PT) symmetry has attracted great interest. However, compared with PT symmetry, there are only a few reported results on its counterpart, anti-PT symmetry, which would lead to new insights and applications. Experimentally simulating and demonstrating the properties of anti-PT symmetry is of particular interest. Here, we present experimental research for simulating the dynamics of bosonic Bogoliubov quasi-particles with anti-PT symmetry based on single photons generated from a point defect in a gallium nitride film. The dynamical evolution under a non-unitary operator is a continuous complex Lorentz transformation in a complex Minkowski space. The evolved states are located on hyperbolic curves, depending on the values of the new defined inner product, which remain invariant during the evolution. Three types of state, space-like, light-like, and time-like, which are analogous to those predicted by the special relativity, are demonstrated. The results of our work could be helpful to investigate the dynamics of quasi-particles in diverse systems and promote deep understanding of non-Hermitian quantum mechanics in open systems.