VecBase, a cloning vector sequence data base.

VecBase, release 2, contains the sequences of 98 cloning vectors in 105 entries. Further additions are made continuously, and VecBase is intended to develop into a central repository for cloning vector sequences. However, as cloning vector sequences are commonly not determined by experiment, but are assembled from the sequences of the parent molecules according to the cloning strategy, they have to be used with extreme caution. To address this problem, VecBase contains an extensive documentation with special emphasis on crossreferences to "parent" sequences and indication of sequence discrepancies. Parent sequences are either themselves cloning vectors present in VecBase, or sequences from one of the major DNA sequence databases. VecBase contains both strands of pUC cloning vectors, because the published sequence displays the polylinker region in its reverse orientation. VecBase is distributed in the standardized format for sequence data exchange. An additional small database called VecSource contains ancillary sequences present in cloning vectors, e.g., polylinkers or promoters.