title: DNA synaptase: an enzyme that fuses DNA molecules at a region of homology.
abstract: This paper describes an enzyme from Escherichia coli, and its purification to apparent homogeneity. The protein, which we call "DNA synaptase" and which may be representative of a class of enzymes, fuses double-stranded DNA molecules at a region of homology. In addition, the purified enzyme is able to catalyze the association of single-stranded DNA with homologous duplex DNA. The genome fusion reaction catalyzed by the purified enzyme occurs in the presence of Mg2+, spermidine, and 2-mercaptoethanol and does not require a high-energy cofactor. By bringing two genomes together at a region of homology, DNA synaptase has a property expected for an enzyme that participates in an early step in genetic recombination. However, the synaptase can be recovered from Rec A- cells, and thus it is not yet possible to determine whether this enzyme plays a role in physiological recombination or in another cellular process that involves genome fusion, such as the recombinational repair of damaged DNA.
mesh_terms: D001426:Bacterial Proteins / Q000302:isolation & purification; D001483:Base Sequence; D004269:DNA, Bacterial / Q000378:metabolism*; D004270:DNA, Circular / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology*; D008025:Ligases / Q000302:isolation & purification* / Q000378:metabolism; D010957:Plasmids; D011995:Recombination, Genetic
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004270:DNA, Circular; D004277:DNA, Single-Stranded; C025922:DNA synaptase; D008025:Ligases