A New Cloning Method for the Preparation of Long Repetitive Polypeptides without a Sequence Requirement

We describe and illustrate a new cloning method for the production of long, size-controlled DNA concatemers, which can be expressed as protein polymers without an amino acid sequence requirement. Synthetic genes encoding different numbers of repeats of the amino acid sequence -(Gly-Lys-Gly-Ser-Ala-Gln-Ala)3- were constructed using this cloning technique. The method enables the production of extremely long synthetic genes (e.g., up to 48 DNA repeats, 3024 bp), in a highly controlled fashion by providing higher-order multimers via the reconcatemerization of pre-multimerized genes and also eliminates the specific sequence requirement of the DNA monomer for restriction endonuclease cleavage. Moreover, the effect of intramolecular cyclization, which has a high probability of occurring during the self-ligation reaction and prevents the cloning of long DNA concatemers, is minimized by this approach. DNA multimers encoding a ladder of four differently sized protein polymers (6, 12, 24, and 48 repeats of a 63-bp s...