If bacteria can solve it, how challenging can it be?

I have always thought that Sudoku was stupid.

In terms of productivity, it is time spent and mental energy expended with nothing to show for it. 

Yes, the solving of the puzzle probably exercises your brain in some way, but I believe that there are more productive, more meaningful ways to exercise your brain that ultimately result is something more significant than a square filled with numbers.

Plus it's just a dumb game.

And now I've learned that a strain of Escherichia coli bacteria has been engineered to solve Sudoku puzzles.

Kind of makes the puzzle seem even stupider now. Huh?