Biology Reference
In-Depth Information
14
CHAPTER
Semi-Synthetic Minimal
Cells: Biochemical, Physical,
and Technological Aspects
Pasquale Stano
1
, Tereza Pereira de Souza
2
, Yutetsu Kuruma
3
, Paolo Carrara
1
and Pier Luigi Luisi
1
1
University of Roma Tre, Rome, Italy
2
Universidade Estadual Paulista Júlio de Mesquita Filho, Sao Jose do Rio Preto, Brazil
3
The Tokyo University, Tokyo, Japan
INTRODUCTION
Synthetic biology (SB) is an offspring of bioengineering that has focused on a very
ambitious aim, that of synthesizing in the laboratory forms of life, or at least biological
structures, which are alternative to natural ones. Thus, the most well-known examples of SB
are in genetic engineering, in the attempt to genetically modify extant bacteria in order to
produce novel bacterial species which are capable of producing fuels, specialized drugs, or
particular biopolymers.
1
Typical in this field is the work by Venter and his group, who
reported the
261
2
And there is much expectation that SB can offer new tools and products, both for therapy
and for bioengineering utilities.
creation of a bacterial cell controlled by a chemically synthesized genome.
'
'
Genetic manipulation is not the only way to SB. In fact, the chemical approach can lead to
biopolymeric structures and to complex supramolecular complexes which are not present in
nature, and are in principle alternative to the extant ones. Examples are the pyranose DNAs
developed by Eschenmoser and his group at the ETH Zurich,
3
or the proteins with a reduced
alphabet of amino acids.
4
These kinds of SBs are referred to as
'
chemical synthetic biology,
'
and our group has been influential in emphasizing the importance of this approach to
SB.
5,6
Genetic engineering and chemical SB also differ in their basic conceptual framework,
and the epistemology of SB has been discussed in such a context.
7
Our group has been active in chemical SB along two lines of research. One is the project on
the so-called
(NBPs). Recognizing that the proteins existing in nature
are only an extremely small fraction of the possible protein structures, we have developed
methods to synthesize in the laboratory libraries of proteins which have never been
produced by nature, or at least which are not present today in our life structures. Here the
questions asked are whether and to what extent these NBPs display novel structures, and
possibly catalysis features, with respect to the natural proteins.
8
Linked to this research are
also basic epistemology questions, for example the controversy between determinism and
contingency in the biogenesis of the fundamental life structure
never born proteins
'
'
like the proteins. The
