Help:An Introduction to BioBricks/BioBrick Part Definition

In specifying your parts you must clearly understand the relationship between parts and plasmids. You must be explicitly aware that a part does NOT include the flanking restriction enzyme sites (called BioBrick prefix and suffix if you are using the BioBrick™ standard for which the restriction enzymes are: EcoRI, XbaI, SpeI, PstI). These sites must instead be specified in the plasmid that your part is in. Your part, then, begins with the first letter (A, C, T, G) following (on the prefix end of the part) or preceding (on the suffix end of the part) whatever cloning sites your plasmid has.