Frequently bricks aren't compatible or affect the expression of other bricks in a totally unpredictable manner. The only way of guaranteeing a working biobrick

Frequently bricks aren't compatible or affect the expression of other bricks in a totally unpredictable manner. The only way of guaranteeing a working biobrick made of many biobricks is to combine as many combinations of biobricks-which-do-the-same-thing as you can find, and use the ones generating the best gene expressions. Even then you might want to take the best 3 or 4 as they will behave differently when combined with other bricks.