Presence of a dipeptidyl aminopeptidase III in Saccharomyces cerevisiae.
作者:Yasuhiro WATANABE、Yuka KUMAGAI、Yukio FUJIMOTO
DOI:10.1248/cpb.38.246
日期:——
The soluble fraction of a cell extract of Saccharomyces cerevisiae was found to contain hydrolytic activity toward arginyl-arginyl-β-naphthylamide (Arg-Arg-βNA). Most of the contaminating Arg-βNA hydrolysis activity was removed by diethylaminoethyl (DEAE)-cellulose column chromatography and the enzyme was partially purified. It is very similar in various properties to mammalian dipeptidyl aminopeptidase III (DAP III), although it differs slightly in some respects.
A reagent for testing periodontal diseases which diagnoses or prognosticates contraction or progress of said diseases by determining aminopeptidase-like enzymatic activity in a specimen, said reagent comprises as a substrate for the enzyme either or both compounds of the formula:
X-Z-Arg-Y [1]
wherein Arg is arginine residue; X is hydrogen or an amino blocking group; Y is a color developing group attached to the C-terminal of Arg; and Z is an amino acid or peptide residue composed of 1 to 4 amino acids or their blocked derivatives, the C-terminal of which is attached to the N-terminal of Arg, and
Xʹ-Zʹ-Pro-Yʹ [2]
wherein Pro is proline residue; Xʹ is hydrogen or an amino blocking group; Yʹ is a color developing group attached to the C-terminal of Pro; and Zʹ is an amino acid or peptide residue composed of 0 to 4 amino acids or their blocked derivatives, the C-terminal of which is attached to the N-terminal of Pro.
一种检测牙周疾病的试剂,它通过测定标本中氨基肽酶样酶的活性来诊断或预测所述疾病的收缩或进展,所述试剂包括作为酶底物的式中的一种或两种化合物:
X-Z-Arg-Y [1]
其中 Arg 是精氨酸残基;X 是氢或氨基封端基;Y 是连接到 Arg C 端的显色基团;Z 是由 1 至 4 个氨基酸或其封端衍生物组成的氨基酸或肽残基,其 C 端连接到 Arg 的 N 端,以及
Xʹ-Zʹ-Pro-Yʹ[2]
其中Pro是脯氨酸残基;Xʹ是氢或氨基封端基;Yʹ是连接到Pro的C-末端的显色基团;Zʹ是由0至4个氨基酸或其封端衍生物组成的氨基酸或肽残基,其C-末端连接到Pro的N-末端。
US5137811A
申请人:——
公开号:US5137811A
公开(公告)日:1992-08-11
Charge transfer in peptides. Effects of temperature, peptide length and solvent conditions upon intramolecular one-electron reactions involving tryptophan and tyrosine
作者:Walter A. Prütz、Edward J. Land、Robert W. Sloper
DOI:10.1039/f19817700281
日期:——
oxidised selectively at the indole group with electron accepting radicals (N˙3 or Br˙–2) in aqueous solution, using pulse radiolysis techniques. Subsequent to the primaryoxidation an efficient synchronous transformation of indolyl into phenoxyl radicals occurred, both in the linear peptides (n= 0, 1 and 2), [graphic omitted] and in c-TrpH-TyrOH. Rate constants of the reactions [1(n)], obtained by kinetic
色氨酰-酪氨酰肽,TrpH-(甘氨酸)ñ -TyrOH和环状的C-TrpH-酪氨酸反应,均在吲哚基团选择性氧化用(N电子接受基团˙ 3或Br ˙- 2)在水溶液中,使用脉冲辐解技术。初次氧化后,线性肽段(n = 0、1和2),[c-TrpH-TyrOH]中都发生了吲哚基向苯氧基的有效同步转化。通过动力学吸收光谱法获得的反应[1(n)]的速率常数遵循经验平方反比关系,k 1(n) / k 1(0)= 1 /(1 + n 2/2),k 1(0) = 7.3×10 4 s –1。观察到反应[1(0)]的热活化,其表观活化能为0.22 eV。添加1.5 mol dm –3尿素(氢键结构的改性剂)或60 mmol dm –3 SDS(屏蔽疏水性吲哚和酚基的去污剂)不会影响反应[1(0)]。TyrOH的OH基团的去质子化(p K a = 10.1)和吲哚基的质子化(p K a = 4.3)有效地提高了自由基的转化率(k