H. Revel

Bio: H. Revel is an academic researcher from University of Chicago. The author has contributed to research in topics: DNA & Gene. The author has an hindex of 2, co-authored 2 publications receiving 338 citations.

McrA and McrB restriction phenotypes of some E.coli strains and implications for gene cloning

Abstract: The McrA and McrB (modified cytosine restriction) systems of E. coli interfere with incoming DNA containing methylcytosine. DNA from many organisms, including all mammalian and plant DNA, is expected to be sensitive, and this could interfere with cloning experiments. The McrA and B phenotypes of a few strains have been reported previously (1-4). The Mcr phenotypes of 94 strains, primarily derived from E. coli K12, are tabulated here. We briefly review some evidence suggesting that McrB restriction of mouse-modified DNA does occur in vivo and does in fact interfere with cloning of specific mouse sequences.

McrAandMcrBrestriction phenotypes ofsomeE.coli strains andimplications forgenecloning

Abstract: TheMcrAandMcrB(modified cytosine restriction) systems ofE.coli interfere withincoming DNA containing methylcytosine. DNA frommanyorganisms, including allmammalian andplant DNA, isexpected tobesensitive, andthis could interfere withcloning experiments. TheMcrAandBphenotypes ofafewstrains havebeenreported previously (1-4). TheMcrphenotypes of94strains, primarily derived fromE.coli K12,aretabulated here. Webriefly review someevidence suggesting thatMcrB restriction ofmouse-modified DNA doesoccurinvivoanddoesinfact interfere withcloning ofspecific mousesequences.

Restriction and Modification Systems

Abstract: BIOLOGY OF RESTRICTION AND MODIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Restriction and modification enzymes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Occurrence of R-M systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Restriction and modification of viruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cloning restriction and modification genes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CHARACTERISTICS OF R-M SySTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . Type I systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Type II systems . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . ...... . ...... . . .. . . . . . . . . . . . . .. . . . . . . . Type lIs systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Type III systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . f!::���:f�':rZ:::;i�g .;;�;��;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: Regulation of expression . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . ...... . . . CONTRASTS AND COMPARISONS AMONG R-M SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . Type I systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Type II systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Type II endonucleases .. ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. . . Methyltransferases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DiSCUSSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Plasmid transformation of Escherichia coli and other bacteria

Abstract: Publisher Summary Escherichia coli is a universal host organism both for molecular cloning of DNA and for a diverse set of assays involving clones genes. This chapter discusses the major techniques and parameters that affect transformation of bacteria, focusing on E.coli . There are two major parameters involved in efficiently transforming a bacterial organism. The first is the method used to induce competence for transformation. There are two primary technical variations in this method: chemical induction of competence and high-voltage electroshock treatment (electroporation). Both the characteristic of the cells being transformed and the purpose of the transformation affect the choice of method. The second major parameter is the genetic constitution of the host strain of the organism being transformed; a variety of genes can dramatically influence the outcome of transformation experiments.