Tuesday, November 23, 2010
Researcher from Tokyo University used E.Coli bacteria to solve a 4x4 game of Sudoku. The key to the “solution” of the puzzle was in two aspects of E. coli: Recombinases, the enzymes used in genetic recombination such as when a damaged cell repairs DNA molecules and antisense RNA.
The system the researchers built involved each bacteria having one of four recombinases, corresponding to the digit (1 through 4) that the particular bacteria represented. Bacteria can “broadcast” their recombinases, so the other bacteria were set up so that as soon as they received three different digits from such broadcasts, they recognized that logically they must represent the remaining digit, and in turn began broadcasting that information themselves.
However, that process only discovers the digit and not the position. To get round this, the researchers assigned antisense RNA corresponding to the lines and mini-grids. The antisense RNA blocked each bacteria from receiving digit information from bacteria that didn’t belong in its vertical line, horizontal line or mini-grid.
To run the simulation, the bacteria that represented digits already filled in at the start of the puzzle were set to broadcast their digit straight away. That kicked off a chain reaction and the puzzle was soon resolved! (Post found on Geeks Are Sexy)
Bacteria Turns Problem Solver