Analysis Note: For the activity assay, use 200 mM potassium cacodylate at pH 7.2, 4 mM MgCl₂, 1 mM 2-mercaptoethanol, 1 mM 3H-dATP, and 70 μM d(pT)₆ at 37 °C.
Bovine terminal transferase (TdT) is a primer-dependent polymerase that catalyzes the addition of deoxynucleotides to the 3′-OH terminus of DNA molecules with the release of inorganic phosphate. TdT reacts preferentially with single-stranded DNA or double-stranded DNA with 3′ overhangs, but methods have been developed to label blunt ends or 3′-recessive ends. The divalent ion (Co²⁺, Mn²⁺, Mg²⁺) influences the polymerization rate of purines and pyrimidines in a reaction mixture. TdT can also be used for non-radioactive and radioactive labeling of the 3′-end of double- and single-stranded DNA, in vitro mutagenesis by adding single nucleotides to DNA, and in TUNEL assays with deoxyuridine triphosphate (dUTP) conjugated to a fluorescent chromophore or biotin.
Unit Definition: One unit will incorporate 1 nanomole of dATP into acid-precipitable material in one hour at 37 °C using d(pT)₆ as a primer.
Physical Form: The enzyme is provided as a solution in 50 mM potassium phosphate, pH 7.4, with 1 mM 2-mercaptoethanol and 50% glycerol (v/v).
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 2,5,8-trithianonane | 37460-04-1 | C6H14S3 | 182.375 |
—— | bis(2-ethylthioethyl)sulfide | 6052-45-5 | C8H18S3 | 210.429 |
1,4,7,10,13-五硫杂环十五烷 | 1,4,7,10,13-pentathiacyclopentadecane | 36338-04-2 | C10H20S5 | 300.599 |
—— | 2,2’-[thiobis(2,1-ethanediylthio)]bis(ethanethiol) | 60147-09-3 | C8H18S5 | 274.561 |
六硫环辛烷 | 1,4,7,10,13,16-hexathiacyclooctadecan | 296-41-3 | C12H24S6 | 360.719 |
1,4,7-三硫环壬烷 | 1,4,7-trithiacyclononane | 6573-11-1 | C6H12S3 | 180.359 |
—— | 1,4,7,10,13,16,19-heptathiaheneicosane | —— | C14H28S7 | 420.838 |