Restriction digests of the clone give the following sizes (kb): EcoRI/XbaI--2.7, 1.4; EcoRI--4.1; BamHI--4.1. The indigo pigment is intracellular and is produced on unsupplemented LB agar. Production is subject to catabolite repression by glucose, but is enhanced by tryptophan, indole, lactose, or IPTG. A high-copy-number cloning vector permitting visual detection of recombinants using insertional inactivation of the Rhodococcus gene for indigo production. Includes priming sites useful for sequencing. The M13 reverse sequencing primer and a 17mer primer [(5'-3') (CGAAGGCCGGTACCAGG)] complementary to the 5' end of the pigment gene (nt 849-832) can be used for sequencing cloned DNA inserts. The order of the major features in this plasmid is: lacOP - EcoRI/MCS/SphI - indigo - lacZ' remnant - ampR - pMB1 ori - lacI. |