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Myxobacteria are special bacteria with wide adaptability, which are rich sources of structurally diverse natural products with intriguing biological properties. Here, a gram-negative myxobacterium strain s54d21 T was isolated from the sediment of a wetland park in China using the Escherichia coli baiting method. Based on 16S rRNA gene sequence and genomic data, the strain was demonstrated to be a novel species of a rare genus Hyalangium , designated Hyalangium ruber sp. nov (type strain s54d21 T  = GDMCC 1.1945 T  = JCM 39263 T ). The subsequent chemical investigation of the strain s54d21 T led to the isolation of three rare 3,5,6-trisubstituted 2(1 H )-pyrazinones, namely, hyalanones A-C ( 1 - 3 ), together with a known macrolactin A ( 4 ). Those new structures and their absolute configurations were unambiguously assigned by extensive analyses of spectroscopic data and density functional theory (DFT) calculations. In biological assays, compound 4 exhibited moderate cytotoxic activities against human cell lines RKO, A549, and NCM460 with IC 50 values ranging from 27.21 to 32.14  μ M., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zang, Zhang, Wang, Tong, Zhou, Yao and Zhu.)

Macrophage migration inhibitory factor (MIF), a multifunctional cytokine, is secreted by various cells and participates in inflammatory reactions, including innate and adaptive immunity. There are some evidences that MIF is involved in many vitreoretinal diseases. For example, MIF can exacerbate many types of uveitis; measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment. MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage. Furthermore, MIF is critical for retinal/choroidal neovascularization, especially complex neovascularization. MIF exacerbates retinal degeneration; thus, anti-MIF therapy may help to mitigate retinal degeneration. MIF protects uveal melanoma from attacks by natural killer cells. The mechanism underlying the effects of MIF in these diseases has been demonstrated: it binds to cluster of differentiation 74, inhibits the c-Jun N-terminal kinase pathway, and triggers mitogen-activated protein kinases, extracellular signal-regulated kinase-1/2, and the phosphoinositide-3-kinase/Akt pathway. MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway. This review focuses on the structure and function of MIF and its receptors, including the effects of MIF on uveal inflammation, retinal degeneration, optic neuropathy, retinal/choroidal neovascularization, and uveal melanoma., Competing Interests: None

Objective: We isolated myxobacteria and explored their diversity from the rhizosphere soils of some medicinal plants., Methods: We used the helper bacteria baiting technique to isolate myxobacteria from the rhizosphere soils collected in South China Botanical Garden and Nanling National Forest Park. The myxobacteria were identified by morphological characteristics and 16S rDNA gene sequences analysis., Results: A total of 50 strains were isolated from 22 soil samples, which were identified into 7 genera, Myxococcus (18), Corallococcus (11), Cystobacter (7), Archangium (8), Stigmatella (1), Chondromyces (4) and Pyxidicoccus (1). The dominant genera were Myxococcus and Corallococcus., Conclusion: Environmental factors were associated with the diversity of myxobactria. Myxobacteria better adapt in high organic matter content and neutral pH environments. The strains of Myxococcus and Corallococcus had a good adaptability for different pH. Meanwhile, the dependence of the strains of Myxococcus and Cystobacter on organic carbon content was not too obvious, and they can also be found in the poor soils. Our findings provided an important scientific base for the development and utilization of myxobacteria resources.

Objective: We isolated myxobacteria in saline-alkaline soils of Xinjiang using a prey-predator strategy where the prey bacteria can induce the predator myxobacteria to form visible fruiting body, and evaluated intrinsic relationships between prey and predator myxobacteria., Methods: Sixteen bacteria with inductive effects of fruiting body formation were obtained, and then used as preys to isolate the myxobacteria., Results: A total of 55 myxobacteria strains were isolated from 25 soil samples, which were identified to the genera of Myxococcus, Corallococcus, Pyxidicoccus, Cystobacter, and Nannocystis. Besides, 6 unpurified isolates were believed to be myxobacteria. All the 16 prey bacteria had preferable inductive effects on Myxococcus spp., whereas Pyxidicoccus spp. and Cystobacter spp. were only induced by Gram-positive strains., Conclusion: The prey-predator strategy provided a new and more effective way to isolate myxobacteria.

Baicalin has been demonstrated to exert anticancer effects mainly through induction of tumor cell apoptosis and cell cycle arrest. However, the precise mechanisms underlying its anticancer role remain to be elucidated. In the present study, we investigated whether autophagy was involved in the anticancer activity of baicalin in the human hepatocellular carcinoma (HCC) cell line SMMC-7721 and the possible molecular mechanisms. Our data showed that the viability of SMMC-7721 cells was significantly inhibited by baicalin in a dose- and time-dependent manner. Alongside apoptosis, autophagy was also induced by baicalin dose- and time-dependently with the involvement of the autophagy-associated protein Βeclin 1. Moreover, we demonstrated that cell death induced by baicalin was significantly inhibited by the apoptosis inhibitor z-DEVD-fmk or the autophagy inhibitor 3-MA, respectively. In addition, we found that CD147, a key molecule related both to apoptosis and autophagy, was markedly downregulated at the protein level in SMMC-7721 cells treated with baicalin. Collectively, this is the first study to suggest that baicalin induces autophagic cell death in SMMC-7721 cells, which involves the downregulation of CD147. Our study reveals a new mechanism for the anticancer effects of baicalin and puts forward a potential crucial role of CD147 in baicalin-induced cancer cell death.

Objective: To isolate myxobacteria and investigate their diversity in saline-alkaline soils from Akesu in Xinjiang., Methods: Conventional culture-dependent methods, e. g. baiting technique, water agar, soil extract agar and mineral agar, were used to isolate myxobacteria from 25 soil samples collected from Akesu areas of Xinjiang. Combining with physicochemical properties (acidity/alkalinity, salt concentration, vegetation and geographical locations) of the soil samples, myxobacterial diversity was studied., Results: In total 58 strains were isolated, and identified as belonging to 6 different genera, i.e. Myxococcus, Cystobacter, Corallococcus, Sorangium, Nannocystis and Polyangium of Myxococcales. The most frequent genus isolated was Myxococcus which may better adapt in harsh environments. Different myxobacterial diversity was detected in different habitat., Conclusion: Myxobacteria diversity was low in saline-alkaline soils of Akesu in Xinjiang.