Control of malaria is threatened by emerging parasite resistance to artemisinin and derivative drug (ART) therapies. The molecular detail of how Plasmodium malaria parasites respond to ART and how this could contribute to resistance are not well understood. To address this question, we performed a transcriptomic study of dihydroartemisinin (DHA) response in P. falciparum K1 strain and in P. berghei ANKA strain using microarray and RNA-seq technology. Microarray data from DHA-treated P. falciparum trophozoite stage parasites revealed a response pattern that is overall less trophozoite-like and more like the other stages of asexual development. A meta-analysis of these data with previously published data from other ART treatments revealed a set of common differentially expressed genes. Notably, ribosomal protein genes are down-regulated in response to ART. A similar pattern of trophozoite transcriptomic change was observed from RNA-seq data. RNA-seq data from DHA-treated P. falciparum rings reveal a more muted response, although there is considerable overlap of differentially expressed genes with DHA-treated trophozoites. No genes are differentially expressed in DHA-treated P. falciparum schizonts. The transcriptional response of P. berghei to DHA treatment in vivo in infected mice is similar to the P. falciparum in vitro culture ring and trophozoite responses, in which ribosomal protein genes are notably down-regulated. Ring and trophozoite stage Plasmodium respond to ART by arresting metabolic processes such as protein synthesis and glycolysis. This response can be protective in rings, as shown by the phenomenon of dormancy. In contrast, this response is not as protective in trophozoites owing to their commitment to a highly active and vulnerable metabolic state. The lower metabolic demands of schizonts could explain why they are less sensitive and unresponsive to ART. The ART response pattern is revealed clearly from RNA-seq data, suggesting that this technology is of great utility for studying drug response in Plasmodium.

The sustainable production of natural compounds is increasingly important in today’s industrial landscape. This study investigates the metabolic engineering of Saccharomyces cerevisiae for the efficient biosynthesis of valuable carotenoids: canthaxanthin, zeaxanthin, and astaxanthin. Utilizing a tailored parental yeast strain, Sp_Bc, we optimized the carotenoid pathway by screening and identifying CrtW and CrtZ enzymatic variants. The CrtW variant from Bradyrhizobium sp. achieved a canthaxanthin titer of 425.1 ± 69.1 µg/L, while the CrtZ variant from Pantoea ananatis achieved a zeaxanthin titer of 70.5 ± 10.8 µg/L. Additionally, we optimized carotenoid production by exploring enzyme fusion strategies for all three studied carotenoids and organelle compartmentalization specifically for enhancing astaxanthin synthesis. We further improved carotenoid production by integrating the optimal gene constructs into the yeast genome and deleting the GAL80 gene, enabling the use of sucrose as a carbon source. The engineered strain Sp_Bc-Can001 ∆gal80 was evaluated in a 5 L bioreactor fermentation, achieving a notable canthaxanthin titer of 60.36 ± 1.51 mg/L using sucrose. This research conclusively establishes S. cerevisiae as a viable platform for efficient carotenoid biosynthesis and, for the first time in this yeast system, illustrates sucrose’s viability as a carbon source for canthaxanthin production. These findings pave the way for sustainable, cost-effective carotenoid production at an industrial scale.

Mesoporous bioactive glass nanoparticles (MBGNs) are promising for bone tissue engineering; however, surgical site infection and oxidative stress often compromise regeneration. To address this, MBGNs co-doped with cerium (Ce), zinc (Zn), and strontium (Sr) were synthesized using a microemulsion-assisted sol-gel route (xCe-yZn-Sr-MBGNs; x = 0, 1, 2; y = 0, 0.5, 1). The resulting spherical nanoparticles (150–200 nm) exhibited a mesoporous structure with a specific surface area of (~340–425 m²/g), sustained ion release, and apatite formation in simulated body fluid. In vitro evaluations with MC3T3-E1 pre-osteoblasts demonstrated dose-dependent cytocompatibility, specifically in the co-doped formulations; however, higher Ce concentrations (2Ce-yZn-Sr-MBGNs) reduced viability following prolonged exposure. Crucially, the 1Ce-1Zn-Sr-MBGNs significantly enhanced osteogenic differentiation, as evidenced by a two-fold increase in osteogenic marker gene expression and a ~45% increase in calcium mineral deposition compared to undoped MBGNs within 14 days. Moreover, these particles accelerated cell migration, achieving ~70% scratch-wound closure within 24 h. Furthermore, 1Ce-1Zn-Sr-MBGNs displayed strong radical scavenging capacity and potent antibacterial activity against S. aureus and P. aeruginosa. These findings indicated that 1Ce-1Zn-Sr-MBGNs exhibited multiple therapeutic effects, including antibacterial, radical-scavenging, and osteogenic effects. By optimizing dopant ratios, these multifunctional nanomaterials emerge as promising candidates for next-generation bone grafts or implant coatings. Within the scope of this study, they demonstrated the capacity to simultaneously address three critical challenges in bone healing: controlling infection, mitigating oxidative stress, and promoting mineralized tissue formation. While these in vitro results provide a robust foundation, further in vivo validation is warranted to confirm their efficacy within complex physiological environments.

In the fight towards eradication of malaria, identifying compounds active against new drug targets constitutes a key approach. Plasmodium falciparum 7,8-dihydro-6-hydroxymethylpterin-pyrophosphokinase (PfHPPK) has been advanced as a promising target, as being part of the parasite essential folate biosynthesis pathway while having no orthologue in the human genome. However, no drug discovery efforts have been reported on this enzyme. In this study, we conducted a three-step screening of our in-house antifolate library against PfHPPK using a newly designed PfHPPK-GFP protein construct. Combining virtual screening, differential scanning fluorimetry and enzymatic assay, we identified 14 compounds active against PfHPPK. Compounds’ binding modes were investigated by molecular docking, suggesting competitive binding with the HMDP substrate. Cytotoxicity and in vitro ADME properties of hit compounds were also assessed, showing good metabolic stability and low toxicity. The most active compounds displayed low micromolar IC₅₀ against drug-resistant parasites. The reported hit compounds constitute a good starting point for inhibitor development against PfHPPK, as an alternative approach to tackle the malaria parasite.