Tuberculosis (TB), one major threat to humans, can infect one third of the worldwide population, and cause more than one million deaths each year. This study aimed to identify the effective diagnosis and therapy biomarkers of TB. Hence, we analyzed two microarray datasets (GSE54992 and GSE62525) derived from the Gene Expression Omnibus (GEO) database to find the differentially expressed genes (DEGs) of peripheral blood mononuclear cell (PBMC) between TB patients and healthy specimens. Functional and pathway enrichment of the DEGs were analyzed by Metascape database. Protein-protein interaction (PPI) network among the DEGs were constructed by STRING databases and visualized in Cytoscape software. The related transcription factors regulatory network of the DEGs was also constructed. A total of 190 DEGs including 36 up-regulated genes and 154 down-regulated genes were obtained in TB samples. Gene functional enrichment analysis showed that these DEGs were enriched in T cell activation, chemotaxis, leukocyte activation involved in immune response, cytokine secretion, head development, etc. The top six hub genes (namely, LRRK2, FYN, GART, CCR7, CXCR5, and FASLG) and two significant modules were got from PPI network of DEGs. Vital transcriptional factors, such as FoxC1 and GATA2, were discovered with close interaction with these six hub DEGs. By systemic bioinformatic analysis, many DEGs associated with TB were screened, and these identified hub DEGs may be potential biomarkers for diagnosis and treatment of TB in the future.

The rapid emergence of multidrug-resistant Shigella dysenteriae strains necessitates new therapeutic approaches, such as phage therapy. Phages are considered a promising adjunct to antibiotics. The rapid emergence of phage-resistant bacterial mutants represents a major challenge in clinical practice. Nevertheless, this sometimes comes with fitness trade-offs. Thus, understanding the fitness trade-offs is crucial prior to phage clinical application. In the present study, a new lytic S. dysenteriae phage, Henu12, was isolated. Henu12 was assigned to the Caudoviricetes class and demonstrated good thermal, pH, and chloroform stability. The phage genome comprises a 69,779 bp linear double-stranded DNA with 90 open reading frames and has the highest similarity with Shigella phage Sf15 and Escherichia phage vB_EcoM_3HA14. Interestingly, the genome did not contain integrases, virulence, or antibiotic resistance genes. A time-kill assay demonstrated synergistic effects with polymyxin B, tetracycline, and ceftazidime. The phage-resistant mutant demonstrated impaired adsorption, downregulation of the tested lipopolysaccharide biosynthetic genes, enhanced sensitivity to polymyxin B and tetracycline, and environmental stressors, impaired biofilm, and diminished in vivo colonization compared to the wild-type strain. The whole-genome resequencing of the phage-resistant mutant identified a multi-base insertion in the waaH gene involved in the lipopolysaccharide biosynthesis pathway, potentially responsible for the phage resistance phenotype, along with other mutations related to the associated trade-offs. Together, these findings provide new insights into the evolutionary interactions between phage resistance and bacterial fitness that could potentially offer a novel approach to treat resistant Shigella dysenteriae infections. IMPORTANCE: Phage therapy is a promising approach to combat the rise of multidrug-resistant bacteria. The emergence of phage-resistant bacterial strains is a potential complication associated with the application of phages. In the current study, we demonstrated that the synergistic use of phage Henu12 in conjunction with antibiotics not only enhances the bactericidal efficacy but also postpones the development of resistant strains. In addition, we provide a better understanding of the fitness trade-off that might fill some gaps in the future success of phage therapies in combating resistant shigellosis in clinical settings.

As the overuse of antibiotics has not yet been strictly limited in urban areas, drug-resistant Escherichia coli has become a fatal pressure for bacteremia treatment. Considering the outstanding performance of bacteriophages in vitro , bacteriophages may serve as an alternative to heal chronic refractory infections. In this study, a 49,890 bp double-stranded circular DNA phage, Henu8, was isolated and was able to lyse the group of E. coli strains tested in this study. Prominent biological characterization revealed that the highly adsorbed bacteriophage Henu8 could form a fully transparent plaque with a narrow translucent halo. The optimal multiplicity of infection of the bacteriophage Henu8 was 0.01, with a burst size of 275 PFU/cell. Genomic analysis revealed a G + C content of 44.17% Henu8, in which 65 open reading frames were located, which could be assigned as a new species in the genus Hanrivervirus of the subfamily Tempevirinae . The effective antibacterial ability and the obvious biofilm destruction and inhibition capability of phage Henu8 were observed. The time-killing assay demonstrated the synergetic potential of Henu8 with antibiotics in vitro for E. coli eradication. Henu8 has profound medicinal potential in a mouse bacteremia model. These studies indicate that Henu8 is a novel bacteriophage with therapeutic potential alone or in combination with antibiotics for clinical treatment. IMPORTANCE: The findings described in this study constitute concrete evidence that it is possible to significantly synergize the antimicrobial activity of bacteriophages and antibiotics. We showed that the newly isolated potent bacteriophage Henu8 lyses Escherichia coli rapidly but tends to produce resistant bacteria. The bacteriophage Henu8 has synergistic antimicrobial effects with several antibiotics and is not susceptible to developing resistance. These results provide further evidence that bacterial resistance to phages arises, possibly at an adaptive cost to sensitivity to antibiotics. Therefore, the findings of this study are important for increasing the potential of phages for clinical applications and developing new approaches to improve their therapeutic efficacy against bacterial drug resistance.

New anti-infective therapies are urgently needed for the treatment of drug-resistant bacterial infections in the context of the rapid spread of drug resistance. Phages, the natural enemies of bacteria, have irreplaceable advantages in the treatment of bacterial infections. Here, we report a novel phage, vB_KpnP_Henu1_3, that specifically lyses capsule-type K1 Klebsiella pneumoniae . The phage vB_KpnP_Henu1_3 shows relatively favorable thermal stability (4°C–55°C) and pH tolerance (pH = 4–11). In addition, the optimal multiplicity of infection is 0.01, with a burst size of approximately 253 ± 54 PFU/cell. Genomic analysis reveals that phage vB_KpnP_Henu1_3 contains double-stranded DNA (total length of 49,808 bp) with a G + C content of 50.76%, and the genome comprises 75 open reading frames with no virulence- or antibiotic resistance-related genes. Transmission electron microscopy observations revealed that phage vB_KpnP_Henu1_3 possessed an icosahedral head and siphovirus morphology. Based on the genome sequence, phage vB_KpnP_Henu1_3 could be assigned to a new species in the genus Webervirus of the family Drexlerviridae . Furthermore, phage vB_KpnP_Henu1_3 rapidly inhibits the growth of K. pneumoniae within 4 h, prevents biofilm formation, and disrupts mature biofilms in vitro . In infection animal models, phage vB_KpnP_Henu1_3 significantly increases the survival rate of K. pneumoniae -infected Galleria mellonella larvae and mice while reducing the bacterial loads. These findings demonstrate that phage vB_KpnP_Henu1_3 has promising potential as a safe alternative for controlling and treating multidrug-resistant K1-type K. pneumoniae infections. IMPORTANCE: The widespread use of antibiotics has led to increasing antibiotic resistance, which is a growing global health concern. Therefore, the development of novel antimicrobial therapy that can cure drug-resistant bacteria-induced infections is imperative. Phages are of increasing interest as natural enemies of bacteria with clear advantages in antibacterial.

The global rise of antibiotic resistance presents a critical public health challenge, with Staphylococcus aureus being a leading cause of hospital- and community-acquired infections. Methicillin-resistant S. aureus (MRSA) is particularly concerning due to its high prevalence, multidrug resistance, and association with severe morbidity and mortality. Developing novel small-molecule antimicrobial agents with reduced resistance susceptibility is essential to combat these infections. From our in-house compound library, we identified YZ462, a heteroaromatic-aryl scaffold compound, demonstrating potent antibacterial activity and low toxicity. YZ462 showed strong anti-MRSA effects through bacterial membrane disruption, increased permeability, and induction of endogenous ROS production. In vitro, it effectively killed both log-phase and stationary-phase MRSA while inhibiting biofilm formation and disrupting established biofilms. In vivo studies revealed significant reduction of bacterial loads and improved survival rates in infected animal models. Importantly, the major S. aureus membrane component cardiolipin (CL) directly interacted with YZ462 and attenuated its antibacterial activity, suggesting CL as a potential molecular target. Our study establishes YZ462 as a promising small-molecule candidate for MRSA treatment, featuring a unique mechanism of membrane disruption and ROS induction. These results confirm its potent antimicrobial activity and demonstrate therapeutic potential against MRSA infections.