Current Microbiology最新文献

Accurate and reproducible descriptions of novel prokaryotic taxa are essential for understanding their evolutionary relationships and ecological roles. This editorial review provides detailed guidelines for standardizing the description of novel taxa, in alignment with the International Code of Nomenclature of Prokaryotes (ICNP). The recommendations focus on essential requirements for documentation, designation, and nomenclature of prokaryotic taxa. This structured approach supports researchers in producing consistent, well-defined descriptions that meet current standards for valid publication and effective classification of novel prokaryotic taxa.

Enterococci are major opportunistic pathogens causing healthcare-associated infections in children. Linezolid, a WHO-designated critically important antibiotic for multidrug-resistant Gram-positive infections, is increasingly challenged by linezolid-non-susceptible enterococci (LNSE). Yet pediatric LNSE epidemiology and genomics data remain scarce, hindering targeted control. We analyzed 26 LNSE strains isolated from Children's Hospital, Zhejiang University School of Medicine (June 2020-July 2024) using MALDI-TOF MS, Vitek2 Compact, micro-broth dilution (for linezolid MIC), MLST, resistance/virulence gene detection, and pan-genome analysis (COG/KEGG annotation). Enterococcus faecalis (E. faecalis) dominated (23/26,88.5%) with ST16 as the major sequence type (ST) and four novel STs identified; all strains harbored optrA and fexA, with species-specific resistance/virulence gene profiles. The 23 E. faecalis strains exhibited an open pan-genome (b = 0.174725), indicating the possible existence of active horizontal gene transfer (HGT), with core, accessory, and unique genes showing distinct functional differentiation. These findings provide critical and robust empirical data to inform the development of targeted prevention and control strategies against LNSE in pediatric populations.

Hepatitis B virus (HBV) is a global public health threat. It has been linked to the development of cirrhosis and hepatocellular carcinoma (HCC) which may lead to different types of liver damage. This review explores the intricate biology of HBV, emphasizing the structure and life cycle of the virus and the role of viral RNAs. Even though new antiviral medications like pegylated interferons alpha and nucleos(t)ide analogues (NA), have been confirmed to be efficient in inhibiting HBV replication, but the developing resistance, side effects of existing drugs and lack of potency to reduce covalently closed circular DNA (cccDNA), are worrisome and indicate the need of new drug development. A thorough understanding of the host virus interaction and the mechanism of immune evasion for viral persistence will help to identify the new drug targets. Currently available vaccines have proven to be effective in the prevention of HBV infection, but the current ongoing research aims to enhance their protection duration, efficacy, and accessibility, using new regimens. The new antiviral/vaccine strategies that have emerged from different discoveries, highlight the significance of further research to create efficient treatments that can accomplish long-term viral suppression and eventually aid in the treatment of HBV infection. The current review summarizes, the understanding of the mechanism of viral replication, different targets for drug development, and strategies to develop the potential vaccine candidates to combat HBV infection.

Echinocandin B (ECB) biosynthesis in Aspergillus nidulans is primarily governed by multiple genes located within the biosynthetic echinocandin (ecd) gene cluster. The contributory functions of many genes, including transcription factors and tailoring enzymes of the ecd gene cluster, have been previously studied. The present study focused on determining the role of transporter proteins, EcdLp, EcdCp, and EcdDp, in ECB efflux using in silico and biochemical approaches. The molecular docking analysis revealed that ECB relatively showed higher binding affinity for EcdLp than the other co-clustered MFS transporters EcdCp and EcdDp, suggesting a preferred substrate of EcdLp. These results were further confirmed by heterologous integration of the ecdL gene in the ABC transporters-deficient Saccharomyces cerevisiae AD1-8u⁻, confirming active efflux. However, the binding of ECB in EcdLp is distinct from the R6G binding, overlapping the promiscuous site of farnesol, resulting in inhibition of R6G efflux in a dose-dependent manner. In conclusion, these results decipher the ECB binding and efflux mechanism and unveil the evolutionarily specialized architecture of EcdLp that permits targeted metabolite export in addition to environmental responsiveness, and lay the groundwork for optimizing ECB production via transporter engineering.

Inclusion body hepatitis (IBH), caused by fowl adenovirus (FAdV) species D and E, results in significant economic losses for the poultry industry. This study aimed to evaluate the immunogenicity of an inactivated trivalent FAdV vaccine in SPF chickens, specifically assessing the effects of antigen payload, thimerosal addition, and booster immunization on antibody titers. Results demonstrated a clear dose-response, with higher antigen payloads eliciting a more prolonged immune response compared to the lowest dose. Thimerosal was confirmed to be a safe preservative, showing no negative impact on antibody development. Furthermore, a booster immunization significantly increased antibody levels, but this effect was observed only in the group receiving the high-payload vaccine, with peak titers at weeks 2 and 3 post-vaccination. These findings indicate that a high-dose trivalent inactivated FAdV vaccine, administered with a booster, is highly immunogenic and represents a promising strategy for the effective prevention and control of IBH.

Microplastic (MPs) pollution has emerged as a significant environmental concern globally, posing threats to ecosystems, human health, and biodiversity. Prior reviews treat biological, engineering, and policy interventions in silos and largely catalog findings without a comparative, decision-oriented synthesis that maps efficacy, limits, scalability, and readiness to concrete deployment contexts. Therefore, this review work provides an integrated, decision-oriented synthesis that jointly evaluates biological, technological, and policy interventions for mitigation. The study finds that filtration is the most deployment-ready option but suffers from fouling and limited capture of the smallest particles, advanced oxidation can work yet is energy- and cost-intensive, while biological/enzymatic routes are promising but slow and scale is limited. Engineered strains can outperform wild types but introduce biosafety and regulatory risks. Looking forward, it emphasizes the necessity for interdisciplinary research and novel technological solutions to address the persistent challenges of MP pollution. The paper concludes with a call for urgent, coordinated action across sectors to develop and implement comprehensive strategies for mitigating this widespread environmental issue.

Trichoderma species are widely distributed soil fungi known for their biocontrol potential and plant growth-promoting properties. However, the diversity of Trichoderma in island ecosystems, such as the Canary Islands, remains underexplored. In this study, we describe Trichoderma ichasaguae sp. nov., a novel species isolated from banana rhizosphere soils in southwestern Tenerife (the island with the largest cultivated area in the Canary archipelago). The species was identified through multilocus phylogenetic analyses (ITS, tef1-α, rpb2) and detailed morphological characterization. Phylogenetic analyses revealed that Trichoderma ichasaguae forms a distinct lineage within the Harzianum section, closely related to T. hortense, T. rugulosum, and T. orarium, but with clear genetic and morphological differentiation. The description of Trichoderma ichasaguae expands our understanding of fungal biodiversity in the Canary Islands and underscores the need for further taxonomic studies in these insular ecosystems.

Candida species are components of the normal intestinal microbiota and are under constant exposure to bacterial metabolites, including secondary bile salts. Secondary bile salts are produced by commensal bacteria in the intestine and not only affect lipid absorption through emulsification but also have great effects on other microorganisms. Here, we examined the effect of a secondary bile salt, sodium deoxycholate (NaDCA), on the formation of biofilms by Candida tropicalis. In contrast to C. albicans, C. tropicalis tended to maintain its absolute biofilm biomass and surface hydrophobicity in the presence of NaDCA. Fluorescent 3D microscopic imaging of the biofilm revealed that NaDCA treatment reduced filamentous projection to the top of the biofilm. RNA-seq analysis revealed that some genes, especially those associated with iron metabolism, were differentially expressed in NaDCA-treated C. tropicalis. Although NaDCA altered the appearance of C. tropicalis biofilms, analysis of the expression of key virulence factor genes encoding agglutinin-like sequences and candidalysin revealed that these genes were less affected by NaDCA in C. tropicalis than in C. albicans. High-iron exposure had a negative effect on C. tropicalis biofilm biomass. These results suggest a difference in the intestinal niche occupied by C. albicans and C. tropicalis according to the local availability of secondary bile salts.