BamHI, from Bacillus amyloliquefaciens H, is a type II restriction-modification system recognizing and cleaving the sequence G--GATCC. The BamHI restriction-modification system contains divergently transcribed endonuclease and methylase genes along with a small open reading frame oriented in the direction of the endonuclease gene. The small open reading frame has been designated bamHIC (for Bam...

We have found that, in the presence of a thermophilic restriction endonuclease, thermophilic DNA polymerase efficiently synthesizes and amplifies DNA in the absence of any added template and primer nucleic acid under isothermal conditions. More than 10 microg of DNA can be synthesized by 1 unit of DNA polymerase in 1 h, and the reaction proceeds until available dNTPs are consumed. We used mostl...

We have determined the structure of a mutant (Q237W) of HhaI DNA methyltransferase, complexed with the methyl-donor product AdoHcy. The Q237W mutant proteins were crystallized in the monoclinic space group C2 with two molecules in the crystallographic asymmetric unit. Protein-protein interface calculations in the crystal lattices suggest that the dimer interface has the specific characteristics...

Restriction endonuclease NarI cleaves DNA using a two-site mechanism, placing it in the Type IIe class of restriction endonucleases. Although these enzymes have very useful recognition sequences, the two-site mechanism limits the practical application. Site preferences often cause incomplete substrate digestion. Oligonucleotide activation of NarI eliminates incomplete digestions, making it poss...

To study the factors essential for a functional restriction system, the PaeR7 restriction-modification system has been introduced and expressed in murine cells. Transfer of this system was accomplished in two steps. First, cells containing sufficient PaeR7 methylase to completely methylate the mouse genome were constructed. In the second step, the mouse metallothionein promoter-regulated, endon...

A method based on RT-PCR and restriction endonuclease digestion of amplified PCR product was used to differentiate rabies laboratory “fixed” and “street” viruses. The primer sets from glycoprotein and nucleoprotein gene of rabies virus were used to amplify 406 and 533 bp amplicons, respectively. After amplification in RT-PCR, the PCR product was digested with HaeIII restriction endonuclease and...

background and purpose: the fusarium species are among the most important fungi in the medical, veterinary and agricultural fields. materials and methods: in the present study, 172 strains of these fungi have been analyzed. the high molecular weight dnas were extracted from 23 reference strains as well as from 149 isolated fusarium species. using the designed nucleotide primers from rdna of fus...

Type II restriction endonucleases (REases) form a large and highly diverse group of enzymes. Even REases specific for a common recognition site often vary in their oligomeric structure, domain organization and DNA cleavage mechanisms. Here we report biochemical and structural characterization of the monomeric restriction endonuclease UbaLAI, specific for the pseudosymmetric DNA sequence 5'-CC/W...