How many computers can fit into a drop of water? Udi Shapiro Ehud Shapiro

Programmable Computer Medicine in 2050: “Doctor in a Cell” Molecular Output Molecular Input Programmable Computer

Scaling electro and bio devices  = 0.25 micron in Pentium II

Scaling electro and bio devices E. Coli 1 micron  = 0.25 micron in Pentium II

E. Coli

E. Coli internals (1Mbyte)

Ribosomes in operation Ribosomes translate RNA to Proteins RNA Polymerase transcribes DNA to RNA

A mechanical computer

A 4 3 5 2 1

B 1a 2a 3a 1b 2b 4a 3a 5a 4a 5a 4b 3b 5b 5b 3b 4b Front Back

Programmable Computer Medicine in 2050: “Doctor in a Cell” Programmable Computer

Automaton A1 accepting inputs with an even number of b ’s A1: even number of b’s

Turing Machine and Finite Automaton

Example Computation

An example computation over abaaba S0-abaaba (S0 S0) S0-baaba (S0 S1) S1-aaba (S1 S1) S1-aba (S1 S1) S1-ba (S1 S0) S0-a (S0 S0) S0 (final state) The input is accepted

A list of all 8 possible transition rules T1: S0 S0 T2: S0 S1 T3: S0 S0 T4: S0 S1 T5: S1 S0 T6: S1 S1 T7: S1 S0 T8: S1 S1

Automata programs used to test the molecular implementation

Molecular realization of Finite Automata Input: DNA S, a rest a’ Software: DNA S, a FokI Hardware: Class-II restriction enzyme FokI, DNA Ligase, ATP as fuel