E. coli plasmids

ColEl Regulation by RNA Hairpins. Rephcation of the E. coli plasmid ColEl is regulated by two short RNA molecules and a protein in a system that provides an example of the unique stmcmral elements accessible to RNA molecules. Multidimensional heteronuclear nmr spectroscopy has been used to characterize the complex formed between the two RNAs (25). Each of the RNA molecules fold back on the other to form a pair of hairpin... 

The principles that govern the delivery of recombinant DNA in clonable form to a host cell, and its subsequent amplification in the host, are well illustrated by considering three popular cloning vectors commonly used in experiments with E. coli—plasmids, bacteriophages, and bacterial artificial chromosomes—and a vector used to clone large DNA segments in yeast. 

Investigators have developed many different plasmid vectors suitable for cloning by modifying naturally occurring plasmids. The E. coli plasmid pBR322 offers a good example of the features useful in a cloning vector (Fig. 9-4) ... 

FIGURE 9-4 The constructed E. coli plasmid pBR322. Note the location of some important restriction sites—for Pstl, fcoRI, Ba/nHI, SalI, and PvuII ampicillin- and tetracycline-resistance genes and the replication origin (ori). Constructed in 1977, this was one of the early plasmids designed expressly for cloning in E. coli. 

FIGURE 9-5 Use of pBR322 to clone and identify foreign DNA in E. coli. Plasmid Cloning... 

FIGURE 25-3 Visualization of bidirectional DNA replication. Replication of a circular chromosome produces a structure resembling the Greek letter theta (0). (a) Labeling with tritium (3H) shows that both strands are replicated at the same time (new strands shown in red). The electron micrographs illustrate the replication of a circular E. coli plasmid as visualized by autoradiography, (b) Addition of 3H for a... 

For complex samples containing several different DNAs, multiplex PCR has been carried out. For instance, on-chip multiplex PCR was achieved on four DNAs representing regions in the bacteriophage A.DNA (199 and 500 bp), Escherichia coli genomic DNA (346 bp), and E. coli plasmid DNA (410 bp). After PCR, the fluorescent intercalating dye (TO-PRO) was added to the PCR reservoir, and CGE separation was performed downstream [929]. 

Fig. 2. The E. coli plasmids, pKRD-2 and pKRD-3, containing the three xylose-metabolizing gene cassette, KK-AR (or A R)-KD...

E. coli Plasmid Vectors Are Suitable for Cloning Isolated DNA Fragments... 

PcoA 99IHWHGI 140KYHSHS 533 HP1HLH0J4 536KCHL1YKMEVQ4 E. coli plasmid RJ1004... 

E. coli plasmid containing cloned DNA construct with a cloramphenicol marker replacing the operon... 

E. coli plasmid containing a cloned DNA constract with spinach psbC up to a conserved Sph I site and a kanamycin marker in the downstream region... 

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