Ahmadu Bello University

Retrograde transport from endosomes to the trans-Golgi network (TGN) is essential for intracellular trafficking, yet its molecular mechanism remains poorly understood. In Fusarium graminearum, 10 Rab GTPases associated with the Golgi-associated retrograde protein (GARP) complex were identified through immunoprecipitation followed by mass spectrometry (IP-MS). Among these, only the deletion of FgRAB6 disrupted the proper localisation of the GARP complex to the TGN. FgRab6 directly interacts with the GARP subunit FgVps52 via a conserved Q73 residue, which is critical for fungal growth and pathogenicity. Notably, this Q73-dependent interaction is evolutionarily conserved across eukaryotic species. Upon GTP activation, FgRab6 recruits FgVps52 to the TGN, thereby facilitating the assembly of the GARP complex through the sequential recruitment of additional subunits, including FgVps51, FgVps53 and FgVps54. The fully assembled GARP complex subsequently recruits the retromer complex and ensures the precise localisation of the SNARE proteins FgSnc1, FgTlg1 and FgTlg2 at the endosomes and the TGN. Disruption of this pathway severely compromises fungal development and virulence. Collectively, these findings identify a FgRab6-GARP-retromer-coordinated vesicle trafficking pathway that mediates the retrograde transport of SNARE proteins, which is critical for the pathogenicity of F. graminearum. This work provides new mechanistic insights into vesicular transport and highlights potential targets for antifungal intervention.

ABSTRACT Background Informal food supply chains in regions affected by conflict present significant risks associated with the transmission of foodborne pathogens and the development of antimicrobial resistance (AMR). The objective of this research is to investigate the prevalence and AMR patterns of Salmonella spp., Shigella spp., and Listeria monocytogenes in poultry feeds and ready-to-eat (RTE) foods available for sale in Maiduguri, located in northeastern Nigeria. Methods A cross-sectional survey was conducted involving the collection of 120 poultry feed samples and approximately 251 samples of RTE foods, with 120 samples specifically designated for the analysis of Listeria. Pathogen isolation was performed using standardized microbiological protocols (ISO/FDA-BAM), and the assessment of AMR was conducted utilizing the disk diffusion method in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines for Shigella (n=5), Salmonella (n=15), and Listeria (n=3) isolates. Prevalence rates were calculated with 95% confidence intervals derived from the Wilson score method. Results The study revealed a prevalence of Salmonella spp. at 10.0% (95% CI 5.8–16.8) in poultry feeds, with a maximum occurrence of 25.0% identified in the Monday Market, contrasting with a prevalence of 2.3% (0.8–6.7) reported in RTE foods, particularly in Bulumkutu fruits and meats from the Custom Market. Shigella spp. was identified in 3.33% (1.3–8.1) of feed samples and in 0.76% (0.1–4.2) of RTE foods, specifically within pineapple. L. monocytogenes was detected in 2.5% (0.8–7.1) of RTE foods, exclusively sourced from Baga Road market, including meat and sala sour milk. The isolates of Salmonella obtained from feeds demonstrated high levels of multidrug resistance (100% to tetracycline and 83.33% to fluoroquinolones), while Salmonella from RTE foods maintained resistance to tetracycline but exhibited a loss of resistance to fluoroquinolones. Notably, L. monocytogenes exhibited 100% resistance to both fluoroquinolones and cephalosporins while remaining sensitive to tetracycline. The presence of coliforms indicated inadequate hygiene conditions in the feeds, with 60.0% of samples showing contamination. Conclusion This initial study, which encompasses multiple pathogens within the conflict-affected region of Maiduguri, reveals significant upstream contamination of Salmonella in poultry feeds. It delineates the risks associated with ready-to-eat (RTE) foods and highlights the exclusive presence of L. monocytogenes in RTE products. Furthermore, the study indicates divergence in antimicrobial resistance (AMR) based on the food matrix. The findings underscore the urgent need for enhanced One Health surveillance, the implementation of improved hygiene practices in feed production, and the regulation of antimicrobial usage in informal poultry systems. Such measures are essential to effectively mitigate foodborne threats and the emergence of antimicrobial resistance in similarly underserved regions.

The quest for sustainable energy systems that function in severe settings has generated interest in microbial fuel cells (MFCs) utilizing radiation-resistant bacteria. These extremophiles, such as Deinococcus radiodurans, Thermococcus gammatolerans, and Rubrobacter radiotolerans, exhibit remarkable DNA repair systems, antioxidative defenses, and protein-protection mechanisms that facilitate prolonged metabolic activity in the presence of strong ionizing radiation. This review aims to critically assess recent advances in electrode nanomaterials, biofilm engineering, and system optimization approaches to improve microbial fuel cell (MFC) performance. In contrast to traditional electrogens like Shewanella oneidensis and Geobacter sulfurreducens, which quickly deteriorate under radiation stress, these organisms preserve their extracellular electron transfer (EET) capability and biofilm integrity in adverse conditions. Their incorporation into MFCs broadens prospective uses in space exploration, radioactive waste treatment, deep subterranean bioenergy extraction, and autonomous environmental surveillance. In interplanetary environments, radiation-resistant microbial fuel cells could supply continuous electricity for life-support systems and instruments in scenarios where solar energy is inconsistent. In nuclear reactors and polluted locations, they could concurrently immobilize radionuclides and produce power for distant sensors. Deep systems may utilize native extremophiles to facilitate seismic and hydrogeological monitoring, whilst autonomous biosensors could function in disaster areas for prolonged environmental surveillance. By integrating extremophile resilience with MFC adaptability, these systems provide a self-sustaining, low-maintenance power source that operates effectively in environments where traditional bio-electrochemical technologies are ineffective. The review examines microbial adaptations to radiation, material degradation in radioactive conditions, electron transport pathways, and the contribution of extremophiles to the enhancement of MFC performance. Utilizing these creatures for energy production signifies a new frontier in bioenergy research, with considerable ramifications for planetary science, nuclear safety, and sustainable infrastructure in harsh conditions.

This study presents the optimization of nickel oxide nanoparticles (NiO NPs) synthesized through an environmentally benign route using Sida acuta (SA) leaf extract as a reducing and capping agent. Taguchi-Grey Relational Analysis (TGRA) was employed to optimize the hydrodynamic diameter (HDD) and polydispersity index (PDI) of the synthesized NiO NPs. Key synthesis parameters (extract concentration, reaction temperature, and reaction time) were varied within an L9 orthogonal array. Using Grey Relational Analysis (GRA), a regression-based model was developed to predict the grey relational grade (GRG) for multi-response optimization. The optimal synthesis conditions (60mg/mL extract concentration, 70°C reaction temperature, and 120min reaction time) produced NiO NPs with an HDD of 62.72nm and a PDI of 0.232. ANOVA identified temperature as the dominant factor governing the size and distribution of the NPs. UV-Vis spectroscopy showed a characteristic absorption peak at 284nm, and XRD confirmed a face-centered cubic crystalline structure with an average crystallite size of 5.99nm. SEM, EDS, and TEM analyses indicated well-dispersed polycrystalline NPs with 80% purity. The synthesized NiO NPs possess physicochemical characteristics that position them as promising candidates for catalytic, sensing, and energy-storage applications. This work demonstrates a statistical-experimental framework for tuning nanoparticle properties through sustainable synthesis routes, highlighting a scalable strategy for precision nanomaterial design.

This study describes the design, synthesis and characterisation of benzimidazole-derived azo dyes. Ten novel azo acid dyes were synthesized from benzimidazole derivatives using H-acid, Gamma acid, J-acid and Tobias acid as the coupling components. The synthesized intermediates and the dyes were characterised and their properties and structures confirmed using UV–Visible, FT-IR and 1H-NMR spectroscopic techniques. The electronic absorption spectra of the synthesized dyes were within the wavelength range of 492‒660 nm in DMF at a uniform absorption intensity ranging from (0.18‒2.03) × 104 L.mol− 1 cm− 1 The FT-IR spectra of all the dyes showed peaks within the range of 3365‒3712 (cm− 1) corresponding to O–H stretching; 3425‒3362 (cm− 1) indicating N–H stretching; 1643‒1476 (cm− 1) confirming the presence of (–N = N-) and 1431.3‒1185 (cm− 1) which are attributed to (S = O) stretching. The 1H-NMR (δ) spectra of the dyes confirmed the presence of methyne (-CH-) groups between the range of 1.50‒1.89 ppm; methylene (-CH2-) groups between 1.27 and 1.47 ppm; methyl (-CH3-) groups between 1.16 and 1.20 ppm; aromatic protons between 6.78 and 8.63 ppm and carboxylic acid (-RCOOH) group between 10.36 and 12.78 ppm.