Molecular Microbiology Research, 2025, Vol.15, No.2, 93-99 http://microbescipublisher.com/index.php/mmr 93 Review Article Open Access From Microbes to Medicines: Strategy, Carrier Design, and the Hard Problem of Targeted Delivery Congbiao You , Xing Zhao Tropical Microbial Resources Research Center, Hainan Institute of Tropical Agricultural Resources, Sanya, 572025, Hainan, China Corresponding email: congbiao.you@hitar.org Molecular Microbiology Research, 2025, Vol.15, No.2 doi: 10.5376/mmr.2025.15.0010 Received: 18 Feb., 2025 Accepted: 30 Mar., 2025 Published: 26 Apr., 2025 Copyright © 2025 You and Zhao, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: You C.B., and Zhao X., 2025, From microbes to medicines: strategy, carrier design, and the hard problem of targeted delivery, Molecular Microbiology Research, 15(2): 93-99 (doi: 10.5376/mmr.2025.15.0010). Abstract “Therapeutic microbiota” usually signals an intentional nudge to the gut ecosystem-deploying live microbes, engineered strains, or products they make-to restore a healthier steady state. Reading the field as a third-year microbiology graduate student, three anchors keep the landscape from blurring: the agents chosen, the mechanisms they trigger, and the delivery routes that make any of it possible. Within that frame, four avenues dominate the literature and most seminar rooms alike: long-standing probiotics, next-generation strains, engineered bacteria, and fecal microbiota transplantation (FMT). These tools surface across gastrointestinal, metabolic, immune, and oncologic indications. Crucially, delivery is not a side quest: biological vehicles, synthetic materials, and stimulus-responsive platforms keep organisms viable and steer them to the right niche; tissue tropism, receptor-ligand logic, and compact biosensing circuits sharpen where and when action occurs. Clinical reports converge on three signals-rebalanced communities, better-tuned immune tone, and effects that stay close to the lesion. The open ends are familiar: safety, regulation, and person-to-person variability. They argue for standardizable manufacturing, individualized plans, and explicit ethical guardrails. Near-term progress, if experience is any guide, will come from combinations-engineered microbes plus nanotechnology, smarter carriers, and in situ sensing-to support precise, scalable therapy for chronic, complex disease. Keywords Probiotic; Engineering bacterium; Targeted delivery; Drug carrier 1 Introduction The intestine is less a tube “full of bacteria” than a wired ecosystem coordinating metabolism and immune tone; when it tilts into dysbiosis, effects spill across digestion, endocrine control, mucosal defense, even neuroimmune circuits (Juarez et al., 2022; Wu et al., 2022; Li et al., 2024). Therapeutic microbiota denotes intentional pushes back toward function-using long-standing probiotics, next-generation strains, or engineered microbes that act under defined cues. Classic Lactobacillus/Bifidobacterium anchor the field, while Akkermansia muciniphila and Faecalibacterium prausnitzii add barrier and anti-inflammatory precision; synthetic biology supplies programmable delivery, and FMT now appears in guidelines for recurrent Clostridioides difficile (Han et al., 2024; Kamath et al., 2025). Relative to many small molecules, these approaches are more “placeable” and often more personal. Evidence spans IBD, metabolic disorders, and selected cancers (Han et al., 2024; Kamath et al., 2025). The twin practical bottlenecks show up in nearly every lab meeting: design strains or consortia that do the job, then deliver them so the job actually gets done (Lin et al., 2021; Fooladi et al., 2023). 2 Types and Mechanisms of Action of Therapeutic Microbiota When we talk about “what the bugs do,” I push students to sort mechanisms before memorizing strain names. Most therapeutic effects fall into a handful of interlocking themes: Colonization resistance and niche competition; Metabolite provisioning (short-chain fatty acids, indoles, bile-acid derivatives); Barrier fortification; and tuning of innate and adaptive immune tone. Different platforms lean on different combinations of these. 2.1 Conventional and next-generation probiotics The veteran genera earn their keep by crowding out opportunists, reshaping pH and bile chemistry, and dialing down epithelial stress-small shifts that sum to resilience (El Hage et al., 2017; Nazli et al., 2022). The field has
RkJQdWJsaXNoZXIy MjQ4ODYzNA==