A responsive living material prepared by diffusion reveals extracellular enzyme activity of cyanobacteria

L Lisa Tang (Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego) N Nathan T. Soulier (Department of Molecular Biology, University of California, San Diego) R Rebecca Wheeler (Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego) J Jonathan K. Pokorski (Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego) J James W. Golden (Department of Molecular Biology, University of California, San Diego) S Susan S. Golden J Jinhye Bae (Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego)

Abstract

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 Synechococcus elongatus sp. PCC 7942 ( S. elongatus ) into nanoclay-poly-N-isopropylacrylamide (NC-PNIPAm), a hydrogel with a cytotoxic precursor, by exploiting its temperature-dependent shape-morphing behavior. Subsequent growth of S. elongatus 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.

Article Details

Volume / Issue Vol. 122, Issue 18
Published May 06, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (7)

L

Lisa Tang

Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego

N

Nathan T. Soulier

Department of Molecular Biology, University of California, San Diego

R

Rebecca Wheeler

Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego

J

Jonathan K. Pokorski

Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego

J

James W. Golden

Department of Molecular Biology, University of California, San Diego

S

Susan S. Golden

J

Jinhye Bae

Aiiso Yufeng Li Family Department of Chemical and Nano Engineering, University of California, San Diego