Taxonomy for Engineered Living Materials

TL;DR

This paper proposes a comprehensive taxonomy for engineered living materials (ELMs), integrating biological and materials classifications to better categorize and guide research in this multidisciplinary field.

Contribution

It introduces the first complete taxonomy for ELMs, hybridizing life and materials classifications, and demonstrates its application to various examples.

Findings

The taxonomy effectively classifies biological and hybrid ELMs.

It aids in understanding the diversity and properties of ELMs.

The framework guides future research and development in the field.

Abstract

Engineered living materials (ELMs) are the most relevant contemporary revolution in materials science and engineering. These ELMs aim to outperform current examples of "smart", active or multifunctional materials, enabling countless industrial and societal applications. The "living" materials facilitate unique properties, including autonomy, intelligent responses, self-repair, and even self-replication. Within this dawning field, most reviews and documents have divided ELMs into biological ELMs, which are solely made of cells, and hybrid living materials, which consist of abiotic chassis and living cells. Considering that the most relevant feature of living material is that they are made of (or include) living cell colonies and microorganisms, we consider that ELMs should be classified and presented differently, more related to life taxonomies than materials science disciplines. Towards solving the current need for the classification of ELMs, this study presents the first complete proposal of taxonomy for these ELMs. Here, life taxonomies and materials classifications are hybridized hierarchically. Once the proposed taxonomy is explained, its applicability is illustrated by classifying several examples of biological ELMs and hybrid living materials, and its utility for guiding research in this field is analyzed. Finally, possible modifications and improvements are discussed, and a call for collaboration is launched for progressing in this complex and multidisciplinary field.