title: [Substrate specificity of Ca2+,Mg2+-dependent DNAase from sea urchin (Strongylocentrotus intermedius) embryos].
abstract: Ca2+,Mg2+-dependent DNAse from sea urchin embryos is specific to the secondary structure of substrates irrespective of the nature of activating cations. The enzyme does not split synthetic single-stranded oligo and polynucleotides, such as d(pTpTpTpCpC), d(pGpGpTpTpT). d(pApApTpTpC), d(pGpApApTpTpC), d(pA)5-poly(dT), d(pApApTpTpC)-poly(dT), poly(dA) and poly (dT) and hydrolyses the double-stranded substrates poly d(AT), poly (dA) . poly (dT) and highly polymerized DNA. Native double-stranded DNA from salmon and phage T7 is split by the enzyme at a higher rate than that of denaturated DNA of salmon and single-stranded DNA of phage M13. The high rate of poly(dA) . poly(dT) and poly d(AT) hydrolysis and the stability of poly(dG) . poly(dC) to the effect of the enzyme suggest a certain specificity of the enzyme to the nature of nitrogenous bases at the hydrolyzed phosphodiester bond of the substrate.
mesh_terms: D000818:Animals; D003851:Deoxyribonucleases / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000201:enzymology; D004706:Endodeoxyribonucleases; D004720:Endonucleases / Q000378:metabolism*; D007700:Kinetics; D009838:Oligodeoxyribonucleotides; D012617:Sea Urchins / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D009838:Oligodeoxyribonucleotides; D003851:Deoxyribonucleases; D004706:Endodeoxyribonucleases; D004720:Endonucleases; C029367:calcium magnesium dependent endodeoxyribonuclease
vernacular_title: Issledovanie substratnoĭ spetsifichnosti Ca2+,Mg2+-zavisimoĭ DNKazy iz émbrionov morskogo ezha Strongylocentrotus intermedius.