Abstract: The present invention provides compositions and improved methods for multi-site directed mutagenesis and DNA shuffling. The present compositions and methods provide increased mutation frequency and increased number of transformants which allow one to sequence only a few clones in order to identify the correct mutants and to obtain the desired mutant by screening large number of transformants in a short time. Moreover, the inclusion of FEN-1, PEF and optimized buffer and cycling conditions provided in the present invention should also facilitate random mutagenized library construction and the mutagenesis of large or difficult templates.

Abstract: This invention provides isolated polynucleotides that encode replication accessory factors. The invention also provides novel DNA replication accessory factors, which have been isolated and purified from the hyperthermophilic archaea Pyrococcus furiosus. The invention also provides various methods of enhancing a nucleic acid polymerase reaction comprising the addition of the replication accessory factors to the reaction. This invention further provides methods of synthesizing, amplifying, and mutagenizing nucleic acids of interest employing the replication accessory factors. This invention also provides kits comprising, at least one of the replication accessory factors. This invention also provides kits useful for various methods that comprise at least one replication accessory factor.

Abstract: This invention provides isolated polynucleotides that encode replication accessory factors. The invention also provides novel DNA replication accessory factors, which have been isolated and purified from the hyperthermophilic archaea Pyrococcus furiosus. The invention also provides various methods of enhancing a nucleic acid polymerase reaction comprising the addition of the replication accessory factors to the reaction. This invention further provides methods of synthesizing, amplifying, and mutagenizing nucleic acids of interest employing the replication accessory factors. This invention also provides kits comprising at least one of the replication accessory factors. This invention also provides kits useful for various methods that comprise at least one replication accessory factor.