[Objective] To explore the potential mechanism by which Prevotella copri promotes atherosclerosis (AS) from the perspective of host-gut microbiota-metabolism. [Methods] ApoE^-/- mice were randomized into four groups (n=8): control group (Chow group, fed with a normal diet), model group (AS group, fed with a high-fat diet), low-concentration P. copri group (P. copri-low group, administrated with P. copri at 10⁹ CFU/mL by oral gavage daily from the first day of feeding with the high-fat diet), and high-concentration P. copri group (P. copri-high group, administrated with P. copri at 10¹¹ CFU/mL by oral gavage daily from the first day of feeding with the high-fat diet). The body weight was measured and recorded weekly to evaluate the weight gain trend. After 5 weeks, oil red O staining was employed to evaluate the aortic plaque area, and enzyme-linked immunosorbent assay (ELISA) was employed to measure lipid levels, on the basis of which the impact of P. copri on AS progression was assessed. Additionally, qPCR was used to detect the abundance of P. copri in the gut, and untargeted metabolomics was employed to analyze the metabolite changes in the feces of mice. [Results] Compared with the Chow group, the AS group showed increases in the body weight, aortic plaque area, and plasma levels of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglycerides (TG) and a decline in the high-density lipoprotein cholesterol (HDL-C) level. The abundance of P. copri in the gut showed no significant difference between the P. copri-low group and the P. copri-high group, indicating that P. copri successfully colonized the gut in both groups. Based on this, the P. copri-low group was selected as the standard concentration group (P. copri group) for further analysis. Compared with the AS group, P. copri colonization in the gut significantly increased the body weight and aortic plaque area and exacerbated dyslipidemia. Metabolomic analysis revealed that P. copri transplantation led to significant increases in the content of several metabolites, including Cer(d18:1/18:1(9Z)), N-palmitoylsphingosine, genistein, adenine, and linoleic acid. KEGG pathway enrichment analysis further indicated that P. copri might contribute to the development and progression of AS through key pathways such as the regulation of ABC transporters, bile acid metabolism, and neuroactive ligand-receptor interactions. [Conclusion] P. copri may exacerbate inflammation and lipid metabolism imbalance by regulating sphingolipid signaling, purine metabolism, and linoleic acid metabolism, thereby promoting the progression of AS.

In the special environment of plateau, adaptive responses and pathological changes occur in the skin of organisms, which include skin barrier dysfunction, skin vasoconstriction disorder, abnormal thickening of the stratum corneum, and fibrous pigment deposition, leading to a high incidence of skin diseases in plateau areas. In the plateau environment, the composition and diversity of skin microbiota change, which may be related to the occurrence and development of skin diseases. This paper reviews the effects of plateau environments on the skin, common skin diseases in plateau environments, and the effects of skin microbiota on skin diseases and discusses the mechanisms by which skin microbiota influences skin diseases in plateau environments.

[Objective] To establish a dual detection method for contaminations by six foodborne pathogens (Cronobacter, Escherichia coli O157:H7, Bacillus cereus, Staphylococcus aureus, Salmonella, and Listeria monocytogenes) in formula milk powder in a rapid manner. [Methods] Enzymatic recombinase amplification (ERA) is a novel isothermal amplification technology that exponentially amplifies trace amounts of DNA or RNA in 10-30 min at 25-42 ℃. The primers and probe of ERA for the detection of Cronobacter were designed. Meanwhile, the ERA primers and probes suitable for the detection of E. coli O157:H7, B. cereus, S. aureus, Salmonella, and L. monocytogenes were screened. Further, through pairwise combination and cross-reactivity analysis, as well as method optimization, the dual ERA detection system was established. The limit of detection and accuracy of the method were determined by application of this method in the detection of simulated contaminations and actual samples. [Results] Three groups of dual ERA systems were established, achieving the detection of six pathogens in 16 min 10 s. The established method showed the sensitivity of 1 ng/μL in the DNA detection of the combinations of Cronobacter with E. coli O157:H7, B. cereus, and S. aureus, while it showed the sensitivity of 10^-1 ng/μL in the DNA detection of Salmonella and L. monocytogenes. The results of the simulation contaminations showed that the limit of detection of the method was 1 CFU/mL. The dual ERA method established in this study was then adopted to detect 37 commercially available formula milk powder samples near the expiration date. The detection rates of B. cereus and L. monocytogenes were 37.84% and 21.62%, respectively. The results were consistent with those of the real-time PCR (industry standard method), confirming the accuracy of the dual ERA method established in this study. [Conclusion] The dual ERA method established in this study exhibits high specificity and high sensitivity. Moreover, it takes merely approximately 25 min from DNA extraction to obtaining the detection results, and it is capable of simultaneously detecting six pathogens, demonstrating high efficiency. This method is of importance for the rapid screening of foodborne pathogens.

Zearalenone (ZEN) is a secondary metabolite produced by the filamentous fungi of Fusarium, causing serious harm to human and animal health. [Objective] To identify a ZEN-degrading strain and investigate its growth and degradation characteristics under different conditions. [Methods] A bacterial strain that can efficiently degrade ZEN was screened out with ZEN as the only carbon source from soil samples of a field with continuous maize cropping in Anhui Province, China. The strain was identified by morphological observation, biochemical tests, and phylogenetic analysis based on 16S rRNA gene sequences. The effects of temperature, pH, and incubation time on the growth rate and ZEN degradation efficiency of the strain were studied. Furthermore, the efficiency of different active components of the strain on ZEN degradation was measured, and the locations of the active components were determined. [Results] A total of 21 ZEN-degrading strains were isolated from the soil samples, among which strain DC-R2 showed the strongest degradation effect and it was identified as Gordonia sp. BHI medium was the optimal medium for the growth of this strain. The optimal culture conditions of the strain for ZEN degradation were 37 ℃ and pH 8.0, under which 100% ZEN (5 μg/mL) was degraded within 6 h. Intracellular enzymes were the main contributors in DC-R2 to ZEN degradation. [Conclusion] We isolated a strain Gordonia sp. DC-R2 capable of efficiently degrading ZEN. The intracellular enzyme present in this strain is the key to the degradation of ZEN. This provides a foundation for the purification of the key degrading enzyme in subsequent work and the potential application.

[Objective] Biofilm formation and adhesion are important indicators for evaluating the beneficial effects of probiotics. However, the relationship of specific genes with the biofilm formation and adhesion of Lactiplantibacillus remains unclear. The rbk gene encodes ribokinase, which is involved in ribose metabolism and may be related to biofilm formation and adhesion. This study aims to analyze the effects of rbk overexpression on the biofilm formation and adhesion of Lactiplantibacillus paraplantrum LR-1, explore the role of this gene in the regulation of quorum sensing (QS) and expression of related genes, and reveal the influencing mechanism of rbk overexpression in bacteria from a metabolic profile perspective. [Methods] L. paraplantarum LR-1 was selected as the target strain, and the shuttle vector pMG76e was used to construct the recombinant strain rbk-pMG76e-LR-1. The overexpression of rbk was confirmed by qRT-PCR and the enzyme activity assay. Crystal violet staining, cell adhesion assay, and qRT-PCR were employed to evaluate the effects of rbk overexpression on biofilm formation, adhesion, and expression of tuf, luxS, and rpoN. Furthermore, untargeted metabolomics analysis was conducted to assess the effect of rbk overexpression on the metabolic profile. Finally, the effect on the biofilm formation and adhesion of LR-1 was verified by exogenous addition of metabolites. [Results] The overexpression of rbk increased the biofilm formation of LR-1 and the adhesion to HT-29 cells by 1.55-2.34 folds and 3.58 folds, respectively. Moreover, the overexpression of rbk up-regulated the expression levels of tuf, luxS, and rpoN by 70.30, 96.94, and 45.61 folds, respectively. The untargeted metabolomics analysis revealed that rbk overexpression led to changes in the abundance of 145 metabolites. Finally, the exogenous addition of l-proline, rhamnose, and nicotinamide adenine dinucleotide (NADH) increased the biofilm formation of LR-1 by 1.27, 1.39, and 1.25 folds and the adhesion by 1.40, 1.41, and 1.52 folds, respectively. [Conclusion] This study demonstrates that rbk can serve as a key target for enhancing the biofilm formation and adhesion of Lactiplantibacillus.

Cotton Verticillium wilt is the most serious disease affecting cotton cultivation, which could cause a significant decrease in cotton yield or even complete crop failure. Cotton Verticillium wilt is caused by the filamentous fungus Verticillium dahliae. The traditional chemical control affects public health and brings about environmental pollution, and the continuous usage has induced the drug resistance of Verticillium dahliae. Therefore, it is urgent to develop environmental friendly and sustainable development control strategies against cotton Verticillium wilt. Biological control has become a good choice to prevent cotton Verticillium wilt. Based on the analysis of the recent research progress, this review discussed the screening, mechanism of action and field application of biocontrol microbial strains against cotton Verticillium wilt, and summarized the research progress of biocontrol microorganisms inhibiting the growth of pathogen through various mechanisms such as competition, antibiotic action, and inducing plant defense response. Although the application prospects of biocontrol microorganisms are expected, they still face challenges such as environmental adaptability, stability, and usage costs of these biocontrol microorganisms. To further improve the practicality of biocontrol microbial strains in agricultural production, future research should focus on genetic improvement of biocontrol microorganisms, development, and application of the microbial agents and so on.

[Objective] Mumps virus (MuV) is the causative agent of mumps. Nowadays, genotype F is widely prevalent in China, while genotype G appears in localized areas and is exhibiting a trend of gradual expansion. To understand the genetic characteristics of genotype G strains in China, we selected two genotype G MuV strains that were isolated from Dalian, Liaoning for analysis. [Methods] The whole genomes of the two strains were sequenced, and the genotypes were determined according to the WHO reference strains. Furthermore, we compared the molecular characteristics among different genotypes and within genotype G. By comparison with the sequences of genotype G strains in other areas of China, we analyzed the features of genotype G MuVs in China, as well as the genetic distance and variations of key antigenic sites between the wild-type genotype G strains and the existing vaccine strains. [Results] The strains isolated in this study both belonged to genotype G, and they showed the nucleotide differences ranging from 4.2% to 6.9% from other 12 genotypes, with the greatest divergence from genotype A. Among the protein coding genes, the SH coding gene exhibited the largest variation, while the NP, M, and L coding genes were conserved. The P, F and HN coding genes demonstrated significant differences among different genotypes. The genotype G strains isolated in this study were closely related to the strain isolated in Jiangsu Province (Jiangsu.CHN/22.13/2), while they were distinct from the strains previously isolated in Liaoning Province. The genotype G strains isolated in this study lacked a N-glycosylation site (aa 12-14) but gained a N-glycosylation site (aa 464-466) in the key epitope of HN protein. In addition, the genotype G strains showed considerable differences in terms of neutralizing epitopes from the genotype A vaccine strain. These differences suggested that the mutations of these sites may potentially reduce the cross-protection effects of vaccine strains against wild-type MuV strains. Although there were some mutations in F protein, the functional region was conserved. [Conclusion] This study details the genotypic characteristics of genotype G MuVs in Dalian, highlighting their high similarities to the genotype G strains in China and the WHO reference strains, while underscoring significant differences from the genotype A vaccine strain used worldwide. These findings suggest the necessity of continuous surveillance of MuV strains in China and further studies of their epidemiology and virology, which could provide references for tracing MuVs, cutting the transmission route, and developing immunization strategies in China.

In the post-antibiotic era, phage therapy becomes a candidate for treating drug-resistant bacteria. Phages are diverse, and jumbo phages are a class of phages with genomes longer than 200 kb. Their large genomes carry abundant functional genes with scattered distribution. Jumbo phages have a variety of unique biological characteristics, such as oversized phage particles, unique replication cycles, and unique structures such as the nucleus-like compartment, the “inner body”, and the long-wavy curly tail fiber. This paper reviews the research progress in jumbo phages, focusing on their biological characteristics, genomes, evolution, and special replication mechanisms and structures. Furthermore, this review explores the application potential of jumbo phages in the treatment of drug-resistant bacterial infection, environmental management, aquaculture, and biocontrol, aiming to provide reference and implications for the research and application of jumbo phages.

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed in the environment and have ecological and environmental toxicological effects. Therefore, the treatment and remediation of PAH-contaminated sites have attracted much attention. Microbial degradation, as one of the remediation methods for PAH pollution, has the advantages of low cost, high efficiency, and environmental friendliness. The co-cultured microbial system usually has better degradation effect, stronger adaptability, and greater resistance to stress than single strains. This paper reviews the microbial species and mechanisms of co-cultured microorganisms for degrading PAHs and points out the strategies for constructing co-culture systems and different microbial combinations, hoping to provide reference for the application of co-cultured microbial flora in the remediation of organically polluted environments.

Streptococcus suis, a major pathogen of pigs, can cause meningitis, septicemia, and arthritis, leading to serious economic losses in the pig industry. In addition, it can also infect humans and result in diseases or death, being a zoonotic pathogen. Therefore, accurate, rapid, sensitive, and simple detection methods are critical for the prevention and control of swine streptococcosis. At present, a variety of detection methods for S. suis have been developed, including traditional detection methods of microbiology, molecular biology, and immunology and emerging technologies such as nanomaterial-based immunosensors, CRISPR-Cas12a system, and matrix-assisted laser desorption ionization-time of flight mass spectrometry. This review summarizes the principles, applications, advantages, and disadvantages of the above methods and introduces the future directions of S. suis detection methods, aiming to provide reference for the prevention and control of swine streptococcosis.