bims-livmat 2026-09-27 papers

bims-livmat

Biomed News

on Living materials

Issue of 2026–09–27
nine papers selected by
Sara Trujillo Muñoz, Leibniz-Institut für Neue Materialien

Metabolism-Driven Morphomechanical Transitions in a Steady-Dynamic Covalent Double Network Living Hydrogel.
Engineered living materials suppress uropathogenic E. coli growth and invasion of urothelial cells through sustained probiotic release.
Bacterial metabolic-immune reprogramming in cancer: from living vectors to engineered biofactories.
Modulating innate immune responses to curli fibers through protein engineering.
Living co-culture fabrication for biologically crosslinked mycelium-cellulose hydrogels and films.
Geometry-Mediated Microgel Structure-Mechanics for Intestinal Region-Specific Probiotic Delivery.
Firewalled synthetic commensal blocks horizontal gene transfer in the gut.
An Engineered Living Artificial Reef Prototype Constructed with Ceramics, Microalgae, and Hydrogels with Potential for Environmental Restoration.
From biological surfaces to engineered systems: how synthetic and systems biology enable biomimetic design.

Small. 2026 Sep 24. e75932

Metabolism-Driven Morphomechanical Transitions in a Steady-Dynamic Covalent Double Network Living Hydrogel.

Junwei Hu, Zhaoxiang Yang, Huilin Wen, Jinhui Xie, Lingfeng Yuan, Ziyi Yu.

  Engineered living materials couple living biochemical activity with synthetic chemical networks yet translating biological processes into reversible structural and mechanical remodeling remains challenging. Here, we report a metabolism-regulated dynamic covalent double network living hydrogel that converts microbial D-glucose consumption into programmable network reconstruction and morphomechanical transitions. The living hydrogel combines a permanent covalent network that maintains structural integrity and microbial confinement, and a phenylboronic acid-poly (vinyl alcohol) dynamic network whose boronate ester equilibrium is regulated by D-glucose. Exogenous D-glucose competitively disrupts dynamic crosslinking, whereas microbial metabolism depletes D-glucose and promotes reconstruction of the dynamic network. This glucose addition-metabolism cycle enables reversible interfacial structural reconfiguration of living hydrogel modules, enhances bulk shrinkage, and converts chemical remodeling into bilayer bending actuation. The hydrogel supports diverse microorganisms, retains spatially confined populations, and undergoes repeated cycles of network reconstruction and mechanical actuation. By integrating actuation and genetically encoded sensing modules, we further construct a potentially recyclable living hydrogel device capable of sequential grasping and IPTG-induced bacterial sensing. This work establishes metabolism-regulated dynamic network reconstruction as a chemical strategy for coupling living biochemical processes with reversible morphology and mechanics in engineered living materials.

Keywords:  boronate ester chemistry; dynamic covalent hydrogels; engineered living materials; hydrogel actuation; microbial metabolism

DOI:  https://doi.org/10.1002/smll.75932
bioRxiv. 2026 Sep 17. pii: 2026.09.15.751868. [Epub ahead of print]

Engineered living materials suppress uropathogenic E. coli growth and invasion of urothelial cells through sustained probiotic release.

Manivannan Sivaperuman Kalairaj, Veerakit Vanitshavit, Iris George, Leroy Arthur, Mustafa K Abdelrahman, Mason C Ansley, Samantha N Goebel, Konstantinos Stamatis, Mia A Walling, Isabel K Murphy, Hayden E Wylie, Kenneth Hoyt, Philippe E Zimmern, Sargurunathan Subashchandrabose, Taylor H Ware.

Recurrent urinary tract infection (rUTI) is a significant public health problem. The most common cause of rUTI is uropathogenic Escherichia coli (UPEC). Antimicrobial prophylactic and therapeutic regimens for rUTI disrupts the microbiome and leads to infection with antimicrobial resistant organisms. Therefore, there is an urgent need to develop microbiome-sparing alternative approaches for preventing rUTI. Asymptomatic bacteriuria (ABU) E. coli strain 83972 (ABEC) outcompetes UPEC in the urinary tract without causing UTI symptoms, but its limited persistence in the bladder restricts its efficacy. Here, we investigate a device made from an engineered living material (ELM) that releases ABEC in a sustained manner as an antibiotic-free platform against UTIs and rUTIs. Using physiologically relevant in vitro models incorporating human urothelial cells, human urine, and periodic urine exchange, we show that ABEC-releasing ELMs suppress UPEC proliferation and inhibit UPEC attachment to and invasion into urothelial cells, particularly when ABEC is maintained at equal or higher levels than UPEC. Because ELMs continuously release ABEC, they sustain competitive pressure even as planktonic bacteria are cleared during voiding, outperforming a single dose of free-floating ABEC. In a rUTI model, sustained ABEC release from ELMs reduces the proliferation and reinvasion of UPEC expelled from infected urothelial cells, while UPEC infiltration into fractured ELMs remains negligible. Finally, we design a first-generation ELM device that can be transurethrally delivered and retained within the mouse urinary bladder, achieving sustained ABEC release in vivo, with ABEC persisting in the bladder, kidneys, and urine for at least 4 days. In summary, we report the development of an ELM device that continuously releases ABEC to suppress UPEC proliferation and urothelial cell invasion in in vitro models of rUTI, and demonstrate sustained ABEC release in vivo in a mouse bladder.

DOI: https://doi.org/10.64898/2026.09.15.751868
J Control Release. 2026 Sep 23. pii: S0168-3659(26)00798-4. [Epub ahead of print] 115394

Bacterial metabolic-immune reprogramming in cancer: from living vectors to engineered biofactories.

Junjie Wu, Lishang Xu, Qi-Wen Chen, Lu Yu, Zhenbao Liu, Anjie Xia.

  Tumor immunotherapy has transformed modern oncology, yet its clinical efficacy against solid tumors remains severely restricted by complex physiological and immunosuppressive barriers. Distinct from passive delivery systems, live bacteria can actively navigate into hypoxic tumor cores and intrinsically modulate local immune networks, making them promising intelligent therapeutic vehicles. In this review, we comprehensively trace their evolution from living vectors to engineered biofactories. We discuss how colonizing bacteria reprogram the tumor microenvironment (TME) via metabolic interventions-lactate depletion, hypoxia relief, arginine/tryptophan modulation, and adenosine degradation-to reverse immunosuppression. Furthermore, we highlight how bacteria enhance therapeutic efficacy by facilitating antigen presentation, sharing bacterial antigens, and sensitizing tumors to immune checkpoint blockade. Moving to programmable systems, engineered bacteria can act as biofactories that enable spatiotemporally controlled release of oncolytic toxins, cytokines, and checkpoint nanobodies via synthetic circuits and optogenetic modules. Additionally, we briefly introduce bacterial derivatives and highlight their unique advantages in expanding the immunotherapeutic landscape. Finally, key clinical translational bottlenecks for bacterial platforms are analyzed. Through continued interdisciplinary innovation, intelligent engineered bacteria with multifaceted sensing capabilities may ultimately lead to long-term patient remission.

Keywords:  Bacterial derivatives; Engineered bacteria; Metabolic intervention; Metabolic–immune reprogramming; Tumor immunotherapy; Tumor microenvironment

DOI:  https://doi.org/10.1016/j.jconrel.2026.115394
Infect Immun. 2026 Sep 21. e0039426

Modulating innate immune responses to curli fibers through protein engineering.

Shanna Bonanno, Rutvi Sheta, Teena Ramu, Shriya Verenkar, Darren Kim, Eva Bessette, Petit Pierre, Neel S Joshi.

  Curli fibers produced by Escherichia coli are functional amyloids that activate Toll-like receptor 2 (TLR2), initiating innate immune responses at mucosal surfaces. While microbiome-derived curli contribute to host-microbe interactions, their intrinsic immunostimulatory activity limits their utility as programmable scaffolds for engineered probiotic systems, and dysregulated TLR2 activation has been associated with inflammatory bowel disease, systemic lupus erythematosus, neurodegeneration, and sepsis. Here, we engineered E. coli Nissle 1917 to produce modified curli fibers designed to reduce TLR2 signaling through two mechanistically distinct strategies: steric shielding via silk-elastin-like protein sequences and direct receptor antagonism via a known TLR2 antagonist, staphylococcal superantigen-like protein 3 (SSL3). Both engineered variants assembled into structurally intact amyloid fibers and exhibited significantly reduced intrinsic TLR2-dependent NF-κB activation in reporter cells. In competitive inhibition assays against structurally diverse TLR2 agonists, the SSL3 fusion achieved near-complete attenuation of TLR2-dependent signaling, maintained under rising agonist load, while steric shielding provided moderate, agonist class-dependent inhibition. In primary human monocyte-derived dendritic cells, the SSL3 fusion robustly attenuated IL-8 secretion and transcriptional induction of IL-8, IL-6, and IL-1β, whereas steric shielding produced only partial attenuation that did not translate to broad inflammatory suppression. These results establish engineered curli as a tunable platform for receptor-specific modulation of innate immune signaling and highlight the broader potential of modular microbial amyloids as programmable interfaces for engineering host-microbe interactions at mucosal surfaces.

Keywords:  Escherichia coli Nissle 1917; Toll-like receptors; curli fibers; engineered living materials; immune modulation; innate immunity; microbial amyloids; mucosal immunity; pattern recognition receptors

DOI:  https://doi.org/10.1128/iai.00394-26
Nat Commun. 2026 Aug 24. pii: 10134. [Epub ahead of print]17(1):

Living co-culture fabrication for biologically crosslinked mycelium-cellulose hydrogels and films.

Bingyu Xia, Yanpei Tian, Qilong Cheng, Huilong Liu, Xiaojie Liu, Zhenyuan Niu, Xiwei Shan, Pengfei Deng, Wenhui Xu, Shubhra Bansal, Tian Li.

Living materials, owing to their inherent capacities for growth, self-healing, sensing, and adaptation, have attracted widespread attention in recent years. However, controlling growth of living matter to achieve robust and tunable material properties remains a challenge. Here, we report a co-culture strategy that integrates mycelial microfibers with bacterial cellulose nanofibers into hierarchical hydrogels and transparent films. The biological crosslinking between fungal cell wall mannans and cellulose chains yields an interpenetrating micro-nano network with enhanced interfacial hydrogen bonding. As a result, the films achieve simultaneous high tensile strength (195.62 ± 9.06 MPa) and toughness (11.51 ± 0.94 MJ m-3), surpassing most reported biodegradable films. The micro-nano architecture also enables wide-range optical tunability: haze increases from 16.0% to 78.5% while maintaining approximately 80% transparency by controlling culture duration. Mycelium/bacterial cellulose films with tailored properties are promising candidates for applications such as radiative cooling coatings on outdoor displays. This strategy demonstrates a generalizable principle for programming material structure and properties through microbial activity, offering a green pathway toward next-generation sustainable films for transparent radiative cooling, flexible electronics, and optical devices.

DOI: https://doi.org/10.1038/s41467-026-76430-6
Adv Mater. 2026 Sep 20. e75011

Geometry-Mediated Microgel Structure-Mechanics for Intestinal Region-Specific Probiotic Delivery.

Shanan Chen, Wei Shang, Qimeng Wang, Jasper Landman, Yoav D Livney, Yuemiao Zhang, Caroline Thum, Shangwu Chen, Zhengyuan Zhai, Xiangyu Liu, Zhaoxiang Ma, Wenxuan Di, Yuan Li.

  The physiological efficacy of functional food ingredients, particularly probiotics is highly dependent on their spatial localization within the intestine. The non-specific delivery of probiotics severely restricts their therapeutic efficacy. Herein, we developed a sustainable, food-grade microgel delivery platform assembled from corncob nanocellulose building blocks with distinct geometries for programmable intestinal probiotic release. Owing to their distinct topological structures and mechanical properties, spherical nanocellulose-based microgels (CNSM) were found to disintegrate in the ileum, while rod-like nanocellulose-based microgels (CNRM) retained intact until reaching the colon, where they subsequently ruptured. Molecular dynamics simulations supported the superior structural stability of CNRM against osmotic swelling, revealing a structure-mechanics driven mechanism for the controlled release pattern. Both microgels significantly enhanced probiotic survival, as well as nanocoating-mediated mucoadhesion and colonization. To maximize functionality, bile salt hydrolase-producing L. plantarum WCFS1 and immunomodulatory L. rhamnosus GG were embedded into CNSM and CNRM, respectively. Consequently, ileum-targeted WCFS1@CNSM significantly ameliorated hypercholesterolemia, accompanied by increased fecal cholesterol excretion and potential modulation of the gut-liver signaling axis whereas colon-targeted LGG@CNRM profoundly alleviated DSS-induced colitis through epithelial barrier restoration and inflammation suppression. This work provides a region-specific delivery strategy for next-generation probiotic therapeutics.

Keywords:  microgels; nanocellulose; oral delivery; probiotics; region‐specific targeting

DOI:  https://doi.org/10.1002/adma.75011
bioRxiv. 2026 Sep 18. pii: 2026.09.17.752456. [Epub ahead of print]

Firewalled synthetic commensal blocks horizontal gene transfer in the gut.

Eric Hu, Kathryn Gorman Durben, Bogdan Budnik, Daniel H Arlow, Sungwhan F Oh, Akos Nyerges.

Synthetic biology enables the rational reprogramming of microorganisms into living therapeutics and agents for bioremediation. However, such genetically modified organisms (GMOs) disseminate their synthetic genetic information into natural microbial communities through horizontal gene transfer (HGT), posing biosafety risks that limit clinical and environmental deployment. Reassigning sense codons to an alternative amino acid identity establishes a genetic firewall that simultaneously prevents incoming and outgoing gene flow, but reported implementations compromise fitness, precluding clinical and industrial use. Here, we overcome this limitation using genome design and laboratory evolution to create a high-fitness genetically firewalled Escherichia coli commensal. By directly altering the amino acid identity of TCA and TCG serine codons in the genetic code without an unassigned intermediate, we establish a robust genetic firewall that remains stable for thousands of generations. This firewalled commensal stably colonizes the mouse gastrointestinal tract for more than 100 days and blocks viral infections and HGT. As the long-term within-gut evolution of this firewalled organism identified adaptive mutations in genes responsible for carbon source utilization, we rationally redesigned the strain's genome to increase fitness. Together, this work establishes a genetically firewalled commensal for safer living therapeutics development and provides a strategy for designing high-fitness, virus- and gene-transfer-resistant organisms for clinical and environmental use.

DOI: https://doi.org/10.64898/2026.09.17.752456
ACS Appl Mater Interfaces. 2026 Sep 24.

An Engineered Living Artificial Reef Prototype Constructed with Ceramics, Microalgae, and Hydrogels with Potential for Environmental Restoration.

Qi Rong Yang, William F Hynes, Beck Walton, Laurie Jin, Ashley M Burtner, Jenan Kharbush, Xavier Mayali.

  Aquatic ecosystems are under stress worldwide due to extreme weather, overfishing, and pollution. Restoration approaches, such as the deployment of artificial reefs, are needed to mitigate this environmental stress. Here, we designed and tested a living artificial reef consisting of a solid calcium carbonate ceramic structure inoculated with microalgae embedded in a hydrogel matrix. The calcium carbonate ceramic structure was sintered at temperatures as low as 500 °C without thermal decomposition in air using only 1 wt % lithium fluoride. Hydrogel encapsulation protected the microalgal cells and allowed them to grow and remain attached to the ceramic surface. We show that small-scale prototype living artificial reefs removed 69 and 81% of the phosphorus and nitrogen, respectively, from estuarine water after incubation in the laboratory for 24 h. Future efforts to optimize geometry, increase scale, and demonstrate field deployment will be necessary to develop this technology as a mechanism to restore nutrient-contaminated aquatic ecosystems.

Keywords:  artificial reef; calcium carbonate; ceramics; hydrogel; microalgae; nutrient removal

DOI:  https://doi.org/10.1021/acsami.6c12877
Front Syst Biol. 2026 ;6 1860815

From biological surfaces to engineered systems: how synthetic and systems biology enable biomimetic design.

Btisème Bendjebour, Clément Iriart, Mathumitha Jeevakumar, William Potié, Lison Salin, Sébastien Urien, Johan Habersetzer, Urielle M'Be, Sophie Mothré, Pierre-Antoine Vigneron, Julien Grimaud.

  Biological surfaces perform a wide range of functions, including communication, molecular exchange, defense, and movement. While these architectures have long inspired biomimetic surface engineering, most existing reviews focus on fabrication methods, often overlooking the biological mechanisms underlying the functions. This review examines how the structural and functional properties of biological surfaces can inform the design of advanced biomimetic systems. Using an integrative framework combining systems and synthetic biology, we establish key design principles derived from biological surfaces and illustrate their translation into engineered systems. Communication mechanisms such as directional reflection and electrochemical signaling, along with exchange processes like aquaporins or vesicle-based delivery, have informed advances in sensing, filtration, and drug delivery. Similarly, defensive strategies, including adaptive camouflage and antimicrobial surface architectures, offer opportunities for protective and responsive designs. In the context of movement, drag-reducing and adhesive surfaces have enabled innovations in robotics, smart textiles, and transport technologies. Systems biology provides quantitative, multiscale models of pattern formation, surface-mediated signaling, and organism-environment interactions, allowing the identification of key design rules. Complementarily, synthetic biology enables the engineering of living cells, tissues, and biohybrid systems capable of producing tailored surface chemistries, multiscale micro-nano architectures, and dynamic or stimuli-responsive behaviors inspired by laboratory observations. By synthesizing principles underlying surface-mediated communication, exchange, defense, and movement, this review outlines how integrating biological insight with systems-level modeling and synthetic engineering can redefine the next-generation of biomimetic designs.

Keywords:  adaptive materials; bioinspired design; bioinspired engineering; biological surfaces; biomimicry; synthetic biology; systems biology

DOI:  https://doi.org/10.3389/fsysb.2026.1860815