Tang Lisa, Soulier Nathan T, Wheeler Rebecca, Pokorski Jonathan K, Golden James W, Golden Susan S, Bae Jinhye
Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego, La Jolla, CA 92093.
Department of Molecular Biology, University of California, San Diego, La Jolla, CA 92093.
Proc Natl Acad Sci U S A. 2025 May 6;122(18):e2424405122. doi: 10.1073/pnas.2424405122. Epub 2025 May 1.
Stimuli-responsive engineered living materials (ELMs) can respond to environmental or biochemical cues and have broad utility in biological sensors and machines, but have traditionally been limited to biocompatible scaffolds. This is because they are typically made by mixing cells into a precursor solution before crosslinking. Here, we demonstrate a diffusion mechanism for incorporating cells of the cyanobacterium sp. PCC 7942 () into nanoclay-poly-N-isopropylacrylamide (NC-PNIPAm), a hydrogel with a cytotoxic precursor, by exploiting its temperature-dependent shape-morphing behavior. Subsequent growth of caused a decrease in the bending curvature and stiffness (local Young's modulus) of NC-PNIPAm due to partial degradation by an unannotated enzyme. Creation and observation of this cyanobacteria-hydrogel ELM showcases a method for diffusing cells into a hydrogel as well as characterizing an extracellular enzyme.
刺激响应型工程活材料（ELMs）能够对环境或生化信号做出响应，在生物传感器和机器中具有广泛用途，但传统上仅限于生物相容性支架。这是因为它们通常是通过在交联前将细胞混入前体溶液中制成的。在此，我们展示了一种扩散机制，通过利用蓝藻PCC 7942（）的温度依赖性形状变形行为，将其细胞掺入纳米粘土-聚-N-异丙基丙烯酰胺（NC-PNIPAm）中，NC-PNIPAm是一种具有细胞毒性前体的水凝胶。随后的生长导致NC-PNIPAm的弯曲曲率和刚度（局部杨氏模量）降低，这是由于一种未注释的酶导致的部分降解。这种蓝细菌-水凝胶ELM的创建和观察展示了一种将细胞扩散到水凝胶中的方法以及表征一种细胞外酶的方法。
