The Chemoton Model

The author considers his chemoton model not as an intermediate station of biogenesis, but as a basic model for living systems. Greatly simplified, the three cycles 

Cycle 1 an autocatalytic chemical cycle which provides material for the other two cycles. 

Cycle 2 the matrix replication cycle. The matrix molecule can multiply by polymerisation in the presence of a component from cycle 1 it contains all the genetic information required by the whole system. 

Cycle 3 this is the membrane growth cycle. The starting material for the outer envelope of the system comes from cycle 1 and is capable of self-organisation processes which lead to the membrane (T. Ganti, 1997). 

According to Popa (2004) the chemoton model is a virtual chemical network and does not promote any specific chemistry . Without doubt, Ganti s model represents an important, well-thought-through model for a primitive living system. 

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Fig-1 Ganti s abstract chemoton model for minimal life. A, are intermediates of the metabolic cycle, pV is a template molecule consisting of n pieces of monomer V, V is the activated monomer, T is the precursor to the membranogenic molecule T. Tm denotes a membrane consisting of m pieces of T. The system works at the expense of the difference between X and Y. Note that all three subsystems are autocatalytic... 

The first model of a system that is capable of growing by metabolism and of dividing by fission was proposed - with the name of chemoton - by Ganti (1975). Such a system receives metabolites from the environment, expels waste products, and performs a metabolic cycle that begins with one molecule and ends by making two of them. The system is therefore autocatalytic, but it is not using enzymes, and this leaves us in the dark about its biological potential. 

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