Original research date December 2010 Neoschizomers are restriction enzymes that recognize the same nucleotide sequence as their prototype but cleave at a different site. In some special applications this is a very helpful feature. Image TaiIMae.JPG thumb 500px Recognition sequences and products of neoschizomers For example Prototype MaeII A CGT produces DNA fragments with a 2 base 5 extension Neoschizomer TaiI ACGT produces DNA fragments with a 4 base 3 extension Prototype ApaI GGGCC C produces DNA fragments with a 4 base 3 extension Neoschizomer Bsp120I G GGCCC produces DNA fragments with a 4 base 5 extension There are also other pairs of neoschizomers. The special class of neoschizomers that cleave at the same site are known as isoschizomer s. References div class references small Rebase restriction enzyme database, http rebase.neb.com rebase div Category Restriction enzymes enzyme stub de Neoschizomer pl Izoschizomery ... more details
Isoschizomers are pairs of restriction enzyme s specific to the same recognition sequence . For example, Sph I CGTAC G and Bbu I CGTAC G are isoschizomers of each other. The first enzyme to recognize and cut a given sequence is known as the prototype, all subsequent enzymes that recognize and cut that sequence are isoschizomers. Isoschizomers are isolated from different strains of bacteria and therefore may require different reaction conditions. An enzyme that recognizes the same sequence but cuts it differently is a neoschizomer . Neoschizomers are a specific type subset of Isoschizomers. For example, Sma I CCC GGG and Xma I C CCGGG are neoschizomers of each other. An enzyme that recognizes slightly different sequence, but produces the same ends is a isocaudomer . In some cases, only one out of a pair of isoschizomers can recognize both the methylated as well as unmethylated forms of restriction sites. In contrast, the other restriction enzyme can recognize only the unmethylated form of the restriction site. This property of some isoschizomers allows identification of methylation state of the restriction site while isolating it from a bacterial strain. For example, the restriction enzymes HpaII & MspI are isoschizomers, as they both recognize the sequence 5 CCGG 3 when it is unmethylated. But when the second C of the sequence is methylated, only MspI can recognize both the forms while HpaII cannot. References cite web url http www.neb.com nebecomm tech reference restriction enzymes isoschizomers.asp? title Isoschizomers at New England Biolabs format work accessdate Category Molecular biology Category Biotechnology Category Restriction enzymes de Isoschizomer pl Izoschizomery ru ... more details
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