bims-livmat 2025-05-25 papers

Microb Biotechnol. 2025 May;18(5): e70164

Bacterial Species in Engineered Living Materials: Strategies and Future Directions.

Hu Wang, Chunzhong Li, Yanmin Wang, Huanming Zhang.

In recent years, there has been a notable increase interest in engineered living materials (ELMs) owing to their considerable potential. One key area of research within this field is the utilisation of various species of bacteria to create innovative living materials. In order to accelerate the advancement of bacterial-based living materials, a systematic summary of bacterial species and their design strategies is essential. Yet, up to this point, no applicable reviews have been documented. This review offers a concise introduction to living materials derived from bacteria, delves into the strategies and applications of each bacterial species in this realm, and provides perspectives and future outlooks in this field.

Keywords: bacteria; biofilm; engineered living materials

DOI: https://doi.org/10.1111/1751-7915.70164

Sci Rep. 2025 May 23. 15(1): 17980

Exploring bacterial cellulose as an engineered living and programmable biomaterial across disciplines through qualitative thematic analysis.

Luis Quijano, Dagmar Fischer, Tiziana Ferrero-Regis, Laura Navone.

Bacterial cellulose is an engineered living material which holds significant potential due to its material properties and broad applicability across scientific and design disciplines. However, challenges in interdisciplinary collaboration, scalability and commercialization have slowed its widespread adoption and integration into industry applications such as fashion and textiles. This study addresses the gap in understanding how bacterial cellulose is perceived, developed, and utilized across scientific and design disciplines. Through 20 semi-structured interviews with scientists and designers around the world, this paper explores the following themes: (1) the human-living material relationship spectrum, which highlights the distinct ways science and design stakeholders interact with bacterial cellulose as a living material; (2) perceptions of a living material made from bacteria; and (3) bacterial cellulose's potential as a programmable biomaterial. Additionally, we employ Bruno Latour's Actor-Network Theory to map the complex network of human and non-human actors shaping bacterial cellulose's trajectory, identifying critical factors such as consumer acceptance, interdisciplinary collaboration, and material culture. By bridging perspectives from science and design, this study offers actionable insights into bacterial cellulose's future as a sustainable and programmable engineered living material, guiding its responsible development and broader adoption across industries.

DOI: https://doi.org/10.1038/s41598-025-01931-1

Synth Biol (Oxf). 2025 ;10(1): ysaf006

Synthetic biology design principles enable efficient bioproduction of Heparosan with low molecular weight and low polydispersion index for the biomedical industry.

Yadira Boada, Marcelo Flores, Martin Stiebritz, Marco Córdova, Francisco Flores, Alejandro Vignoni.

Heparosan is a natural polymer with unique chemical and biological properties, that holds great promise for biomedical applications. The molecular weight (Mw) and polydispersion index (PDI) are critical factors influencing the performance of heparosan-based materials. Achieving precise control over the synthesis process to consistently produce heparosan with low Mw and low PDI can be challenging, as it requires tight regulation of reaction conditions, enzyme activity, and precursor concentrations. We propose a novel approach utilizing synthetic biology principles to precisely control heparosan biosynthesis in bacteria. Our strategy involves designing a biomolecular controller that can regulate the expression of genes involved in heparosan biosynthesis. This controller is activated by biosensors that detect heparosan precursors, allowing for fine-tuned control of the polymerization process. Through this approach, we foresee the implementation of this synthetic device, demonstrating the potential to produce low Mw and low PDI heparosan in the probiotic E. coli Nissle 1917 as a biosafe and biosecure biofactory. This study represents a significant advancement in the field of heparosan production, offering new opportunities for the development and manufacturing of biomaterials with tailored properties for diverse biomedical applications.

Keywords: Biomanufacturing; heparosan; polydispersion index; synthetic biology

DOI: https://doi.org/10.1093/synbio/ysaf006

Bioact Mater. 2025 Aug;50 556-570

Microenvironment-responsive living hydrogel containing engineered probiotic for treatment of massive bone defects.

Haoyu Fang, Yanyi Wang, Li Li, Xiaotong Qin, Daoyu Zhu, Pei Liu, Qianhao Yang, Youshui Gao, Zhongmin Shi, Xin Ma, Chao Zhong, Yixuan Chen.

Self-activating and microenvironment-responsive biomaterials for tissue regeneration would address the escalating need for bone grafting, but remain challenging. The emergence of microbial living therapeutics offers vast potential in regenerative medicine, as genetically engineered probiotics possess efficient stimuli-responsiveness and tunable biological functions. Here, using elevated endogenous nitric oxide (NO) signals as a biological trigger in bone fracture injuries, a Living Responsive Regenerative Medicine (LRRM) strategy for in situ bone defect repair through real-time controlled release of bone morphogenetic protein-2 (BMP2) is proposed. The Escherichia coli Nissle 1917 (EcN) strain, genetically engineered to sense NO signals and correspondingly produce and secrete BMP2, was firstly encapsulated in gelatin methacryloyl (GelMA) microspheres and then embedded in a bulky hyaluronic acid methacryloyl (HAMA) hydrogel to form a living hydrogel device that circumvents immune attack and prevents bacterial leakage. In vivo multiple bone defect models demonstrated the efficacy of the living hydrogel in enhancing the maturation of bone callus, promoting neovascularization, and facilitating full-thickness bone union. Strategic incorporation of engineered probiotics and the bilayer-structured encapsulation system may emerge as an effective and microenvironment-responsive medicine approach for tissue regeneration.

Keywords: Bacterial engineering; Living hydrogel; Regenerative medicine; Sensing-reporting; Smart biomaterial

DOI: https://doi.org/10.1016/j.bioactmat.2025.04.020