The Experts below are selected from a list of 19290 Experts worldwide ranked by ideXlab platform
Daniel R Cameriniotero - One of the best experts on this subject based on the ideXlab platform.
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long range mapping of gaps and telomeres with reca assisted Restriction Endonuclease rare cleavage
Nature Genetics, 1994Co-Authors: Lance J Ferrin, Daniel R CamerinioteroAbstract:RecA-assisted Restriction Endonuclease (RARE) cleavage is a method to perform sequence-specific cleavage of genomic DNA, and is useful in physical mapping studies. After making two modifications, we have applied this method to mapping large regions of DNA in several cell types, including a notorious gap near the Huntington disease (HD) locus on chromosome 4. RARE cleavage fragments were analysed by pulsed field gel electrophoresis and Southern blotting and the distances between cleavage sites determined with accuracy. Using RARE cleavage, the gap measured was less than 60 kilobases in length. RARE cleavage is also a straightforward technique to map the distance from a marker to a telomere. The terminal 1.7 megabases of several HD and control cell lines were mapped with no large differences between cell lines in this region.
Lance J Ferrin - One of the best experts on this subject based on the ideXlab platform.
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long range mapping of gaps and telomeres with reca assisted Restriction Endonuclease rare cleavage
Nature Genetics, 1994Co-Authors: Lance J Ferrin, Daniel R CamerinioteroAbstract:RecA-assisted Restriction Endonuclease (RARE) cleavage is a method to perform sequence-specific cleavage of genomic DNA, and is useful in physical mapping studies. After making two modifications, we have applied this method to mapping large regions of DNA in several cell types, including a notorious gap near the Huntington disease (HD) locus on chromosome 4. RARE cleavage fragments were analysed by pulsed field gel electrophoresis and Southern blotting and the distances between cleavage sites determined with accuracy. Using RARE cleavage, the gap measured was less than 60 kilobases in length. RARE cleavage is also a straightforward technique to map the distance from a marker to a telomere. The terminal 1.7 megabases of several HD and control cell lines were mapped with no large differences between cell lines in this region.
Ralph A D Williams - One of the best experts on this subject based on the ideXlab platform.
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two thermostable type ii Restriction Endonucleases from icelandic strains of the genus thermus tsp4c i acn gt a novel type ii Restriction Endonuclease and tsp8e i an isoschizomer of the mesophilic enzyme bgl i gccnnnn nggc
Biochemical Journal, 1995Co-Authors: Simon G Welch, Ralph A D WilliamsAbstract:Sixteen isolates of thermophilic bacteria from the genus Thermus, isolated from neutral and alkaline hot water springs in the southwest region of Iceland, were tested for the presence of Restriction Endonucleases. Extracts from five of the isolates showed evidence of the presence of Restriction Endonuclease activity by producing discrete nucleotide fragments when incubated at 65 degrees C with lambda phage DNA. Two of the isolates (Tsp4C and Tsp8E) were found to have particularly high levels of Restriction Endonuclease activity, and the respective enzymes from these two Thermus isolates were partially purified and characterized and their recognition and cleavage sites were determined. Enzyme Tsp4C I is a novel Type II Restriction Endonuclease recognizing the interrupted palindromic tetranucleotide sequence ACNGT, where N can be any one of the four bases in DNA. Tsp4C I, which retains full enzyme activity when incubated for 10 min at temperatures up to 76 degrees C, hydrolyses the phosphodiester bond in both strands of a double-stranded DNA substrate between the third and fourth bases of the recognition sequence (ACN/GT), generating fragments with a single base 3'-OH overhang. Enzyme Tsp8E I is a thermostable isoschizomer of the mesophilic Type II Restriction Endonuclease Bgl I (GCCNNNN/NGGC) [Lee, Clanton and Chirikjiam (1979) Fed. Proc. 28, 294], generating fragments with a three base 3'-OH overhang. However, unlike Bgl I, Tsp8E I exhibits considerable thermal stability, retaining full enzyme activity when incubated for 10 min at temperatures up to 78 degrees C. Both Tsp4C I and Tsp8E I represent significant additions to the small but expanding list of the extremely thermostable Restriction Endonucleases.
Alfred Pingoud - One of the best experts on this subject based on the ideXlab platform.
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does the Restriction Endonuclease ecorv employ a two metal ion mechanism for dna cleavage
Biochemistry, 1997Co-Authors: Detlef H. Groll, Albert Jeltsch, Ursel Selent, Alfred PingoudAbstract:Two models for the catalytic mechanism of the Restriction Endonuclease EcoRV exist which differ in the number and function of metal ions proposed to be directly involved in catalysis. In one model, two metal ions bound by Glu45, Asp74, and Asp90 are assumed to have a direct catalytic function; in the other, only one metal ion bound by Asp74 and Asp90. We show here that in the presence of Mn2+, the catalytic activity of an EcoRV-E45A mutant is only slightly reduced (1.8-fold) as compared to wild type EcoRV and that the single-turnover rate constant of DNA cleavage by E45A is reduced only 39-fold, whereas the D74A and D90A mutants are catalytically inactive under all conditions. These findings make an important catalytic function of Glu45, like binding of an essential divalent metal ion, unlikely. In addition, we have analyzed the dependence of the DNA cleavage rate by EcoRV and EcoRV mutants on the concentration of Mg2+ and Mn2+. We found for the wild type enzyme a sigmoidal dependence of the rate of DNA c...
A Janulaitis - One of the best experts on this subject based on the ideXlab platform.
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aari a Restriction Endonuclease from arthrobacter aurescens ss2 322 which recognizes the novel non palindromic sequence 5 cacctgc n 4 8 3
Nucleic Acids Research, 2002Co-Authors: Rasa Grigaite, Z Maneliene, A JanulaitisAbstract:A new type II Restriction Endonuclease AarI has been isolated from Arthrobacter aurescens SS2-322. AarI recognizes the non-palindromic heptanucleotide sequence 5′-CACCTGC(N)4/8-3′ and makes a staggered cut at the fourth and eighth bases downstream of the target duplex producing a four base 5′-protruding end. AarI activity is stimulated by oligodeoxyribonucleotide duplexes containing an enzyme-specific recognition sequence.
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bfii a Restriction Endonuclease from bacillus firmus s8120 which recognizes the novel non palindromic sequence 5 actggg n 5 4 3
Nucleic Acids Research, 1998Co-Authors: Jūratė Vitkutė, M Petrusyte, Z Maneliene, A JanulaitisAbstract:A new type IIS Restriction Endonuclease Bfi I hasbeen partially purified from Bacillus firmus S8120. Bfi I recognizes the non-palindromic hexanucleotide sequence 5'-ACTGGG(N)5/4-3' and makes a staggered cut at the fifth base pair downstream of the recognition sequence on the upper strand, producing a single base 3' protruding end.
