MacVector incorporates no less than THREE different de novo assemblers, phrap, velvet and SPAdes. While all are great assemblers, with each having their own specific advantages, none of them will generate a circular sequence from input reads. However, MacVector also includes a tool to help you with this. If you are assembling reads representing plasmid sequences, or if you are closing gaps in a circular genome, you can find out if a contig can be circularized by double-clicking on it in the Assembly Project and then right-clicking* in the Contig Editor to bring up a context-sensitive menu.
The algorithm looks for a perfect overlap between the ends of at least 20 bases. If no overlap exists, the menu item is greyed out and reads “Cannot Circularize Consensus”. Otherwise it indicates the length of the overlap. If you select the menu item, a new sequence window opens containing the circularized consensus of the contig, with all gaps removed.
*To right click with a trackpad hold down [CTRL] and click once or tap with two fingers. MacVector has many “right click” menus with extra functionality.
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