Lanthanide spectroscopic studies of the dinuclear and Mg(II)-dependent PvuII restriction endonuclease.

Type II restriction enzymes are homodimeric systems that bind four to eight base pair palindromic recognition sequences of DNA and catalyze metal ion-dependent phosphodiester cleavage. While Mg(II) is required for cleavage in these enzymes, in some systems Ca(II) promotes avid substrate binding and sequence discrimination. These properties make them useful model systems for understanding the roles of alkaline earth metal ions in nucleic acid processing.

The UV response in Saccharomyces cerevisiae involves the mitogen-activated protein kinase Slt2p.

Exposure to UV causes a response in yeast and mammalian cells, which is distinct from the response to DNA damage. We report that the mitogen-activated protein kinase Slt2p is involved in this response in Saccharomyces cerevisiae. Thus, budding yeast and mammalian cells respond to UV by using very similar signal transduction pathways.

Binding and conformational analysis of phosphoramidate-restriction enzyme interactions.

Phosphoramidates are modified deoxyoligonucleotides that feature nitrogen in place of the 3'-oxygen of a phosphodiester linkage. Noted for stability against nuclease activity, these linkages are of both mechanistic and therapeutic interest. While a number of studies characterizing the properties of oligonucleotides composed entirely of phosphoramidate linkages have been published, little is known about how singly substituted phosphoramidate substitutions affect the thermodynamics and structure of protein-oligonucleotide interactions.

Investigation of restriction enzyme cofactor requirements: a relationship between metal ion properties and sequence specificity.

Restriction enzymes are important model systems for understanding the mechanistic contributions of metal ions to nuclease activity. These systems are unique in that they combine distinct functions which have been shown to depend on metal ions: high-affinity DNA binding, sequence-specific recognition of DNA, and Mg(II)-dependent phosphodiester cleavage. While Ca(II) and Mn(II) are commonly used to promote DNA binding and cleavage, respectively, the metal ion properties that are critical to the support of these functions are not clear.