Restriction endonucleases.

This review provides a comprehensive account of the current status of the biology and biochemistry of restriction endonucleases. Both Class I and Class II restriction endonucleases will be considered. However, emphasis will be placed on the Class II group, which recognizes and cleaves a specific duplex DNA sequence. Their occurrence, purification, and characterization is discussed in detail. The characterization includes physical mapping information and determination of recognition sequences. In addition to detailed discussions of the biochemical properties of the enzymes, considerable attention is paid to the uses of these enzymes as tools for research in molecular biology. These uses include physical mapping of genomes and their transcripts, genetic analysis (marker rescue, etc.), DNA sequence analysis, analysis of complex genomes, and genetic engineering. Specific examples of each use are outlined. Practical aspects of both the isolation and use of the restriction endonucleases form the major theme of this review.