, Volume 93, Issue 1, pp 1–13 | Cite as

Approaches to semi-synthetic minimal cells: a review

  • Pier Luigi LuisiEmail author
  • Francesca Ferri
  • Pasquale Stano


Following is a synthetic review on the minimal living cell, defined as an artificial or a semi-artificial cell having the minimal and sufficient number of components to be considered alive. We describe concepts and experiments based on these constructions, and we point out that an operational definition of minimal cell does not define a single species, but rather a broad family of interrelated cell-like structures. The relevance of these researches, considering that the minimal cell should also correspond to the early simple cell in the origin of life and early evolution, is also explained. In addition, we present detailed data in relation to minimal genome, with observations cited by several authors who agree on setting the theoretical full-fledged minimal genome to a figure between 200 and 300 genes. However, further theoretical assumptions may significantly reduce this number (i.e. by eliminating ribosomal proteins and by limiting DNA and RNA polymerases to only a few, less specific molecular species). Generally, the experimental approach to minimal cells consists in utilizing liposomes as cell models and in filling them with genes/enzymes corresponding to minimal cellular functions. To date, a few research groups have successfully induced the expression of single proteins, such as the green fluorescence protein, inside liposomes. Here, different approaches are described and compared. Present constructs are still rather far from the minimal cell, and experimental as well as theoretical difficulties opposing further reduction of complexity are discussed. While most of these minimal cell constructions may represent relatively poor imitations of a modern full-fledged cell, further studies will begin precisely from these constructs. In conclusion, we give a brief outline of the next possible steps on the road map to the minimal cell.


Green Fluorescence Protein Minimal Cell Early Cell Cellular Life Giant Vesicle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank the ‘Enrico Fermi’ Study Center (Rome) and COST D27 Action for financial support.


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Pier Luigi Luisi
    • 1
    Email author
  • Francesca Ferri
    • 2
  • Pasquale Stano
    • 1
    • 3
  1. 1.Biology DepartmentUniversity of RomaTreRomeItaly
  2. 2.Biochemistry DepartmentUniversity of BolognaBolognaItaly
  3. 3.Centro Studi ‘E. Fermi’RomeItaly

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