Hiratsuka T
Department of Chemistry, Asahikawa Medical College, Hokkaido.
J Biochem. 1987 Jun;101(6):1457-62. doi: 10.1093/oxfordjournals.jbchem.a122015.
7-Diethylamino-3-(4'-isothiocyanatophenyl)-4-methylcoumarin (CPI), rhodamine B isothiocyanate (RITC), and 4-bromomethyl-6,7-dimethoxycoumarin (BDMC), fluorescent reagents that can react covalently with amino or sulfhydryl groups, have been used to label myosin subfragment-1 (S-1) ATPase. The conditions under which CPI, RITC, and BDMC selectively label the 50-, 26-, and 20-kDa segments of the S-1 heavy chain, respectively, are described. CPI and RITC labeling little affects the ATPase activities of S-1 in the presence and absence of actin. BDMC labeling activates the Ca2+- and Mg2+-ATPases of S-1, and abolishes the K+-EDTA-ATPase. The three S-1 derivatives fluoresce strongly even under acidic conditions, suggesting the wide applicability of these fluorescent reagents as selective labels for the three segments of the S-1 heavy chain.
7-二乙氨基-3-(4'-异硫氰酸苯酯基)-4-甲基香豆素（CPI）、异硫氰酸罗丹明B（RITC）和4-溴甲基-6,7-二甲氧基香豆素（BDMC）是能与氨基或巯基发生共价反应的荧光试剂，已被用于标记肌球蛋白亚片段1（S-1）ATP酶。本文描述了CPI、RITC和BDMC分别选择性标记S-1重链的50 kDa、26 kDa和20 kDa片段的条件。在有和没有肌动蛋白存在的情况下，CPI和RITC标记对S-1的ATP酶活性影响很小。BDMC标记可激活S-1的Ca2+ - 和Mg2+ -ATP酶，并消除K+ -EDTA-ATP酶。即使在酸性条件下，这三种S-1衍生物也能强烈荧光，表明这些荧光试剂作为S-1重链三个片段的选择性标记具有广泛的适用性。
