Specificity of C-Reactive Protein for Choline Phosphate Residues of Pneumococcal C-Polysaccharide
Specificity of C-Reactive Protein for Choline Phosphate Residues of Pneumococcal C-Polysaccharide
复制标题
C 反应蛋白对肺炎球菌 C 多糖磷酸胆碱残基的特异性
DOI：
--
复制
发表时间：
1971
期刊：
影响因子：
--
通讯作者：
M. Kaplan
中科院分区：
文献类型：
--
作者：
J. Volanakis;M. Kaplan
C-反应蛋白（CRP）是一种急性时相蛋白，在多种病理状态下出现于人血清中，常被用作急性炎症的临床指标。在Ca离子存在下，肺炎球菌C-多糖使其从血清中沉淀出来。虽然这种导致CRP发现的沉淀反应已经知道很多年了，但是关于C-多糖分子中参与与CRP反应的活性位点的信息很少。最近有报道磷酸胆碱是C-多糖的大分子结构单元（1，2）。为了确定CRP对C-多糖磷酸胆碱残基的特异性，我们进行了CRP-C-多糖沉淀的定量抑制研究。测试抑制作用的物质包括磷酸胆碱和一系列有机磷酸酯。这些实验的结果表明，磷酸胆碱是迄今所描述的CRP-C-多糖沉淀的最有效的抑制剂，并表明该化合物可能提供C-多糖的主要反应位点。单批CRP阳性血清（编号9 E.M.），在手术后2天从患有股骨转子间骨折的患者中获得，用于下述所有抑制实验。通过针对商业抗血清（Hyland Labs，洛杉矶，加州）的毛细管沉淀测试，该血清给出CRP的4+反应。该血清的结果代表了其他CRP阳性血清获得的数据。采用安德森和麦卡蒂（3）的方法从肺炎球菌的III R菌株中制备C-多糖。对从药物来源获得的以下物质进行了抑制作用试验，无需进一步纯化：氯化磷酸胆碱、o-磷酸乙醇胺、DL-α-甘油磷酸、β-甘油磷酸、L-α-甘油磷酸胆碱、胆碱碱、尿苷-5 ′-单磷酸（UMP）、腺苷-5 ′-单磷酸（AMP）和胞苷-5 ′-单磷酸（CMP）。
C-reactive protein (CRP) is an acute phase protein appearing in the serum of man during various pathological conditions, and frequently employed as a clinical index of acute inflammation. It is precipitated from the serum by pneumococcal C-polysaccharide in the presence of Ca ions. Although this precipitation reaction, which led to the discovery of CRP, has been known for many years, there is little information about the active site(s) in the molecule of C-polysaccharide participating in the reaction with CRP. It has been recently reported that choline phosphate is a unit of the macro-molecular structure of C-polysaccharide (1, 2). In an attempt to determine the specificity of CRP for choline phosphate residues of C-polysaccharide, we conducted quantitative inhibition studies of CRP-C-polysaccharide precipitation. The substances tested for inhibitory effect included choline phosphate and a series of organic phosphate menoesters. The results of these experiments indicated that choline phosphate is the most active inhibitor of CRP-C-polysaccharide precipitation yet described, and suggested that this compound might provide the major reacting site of C-polysaccharide. A single lot of CRP-positive serum (no. 9 E.M.), obtained 2 days following surgery from a patient with an intertrochanteric fracture of the femur, was used for all the inhibition experiments described below. Tested by capillary precipitation against a commercial antiserum (Hyland Labs, Los Angeles, California), this serum gave a 4+ reaction for CRP. The results with this serum were representative of data obtained also with other CRP-positive sera. C-polysaccharide was prepared by the method of Anderson and McCarty (3) from a III R strain of pneumococcus. The following substances obtained from commerical sources were tested for inhibitory effect without further purification: Choline phosphate chloride, o-phosphoryl-ethanol-amine, DL-α-glycerophosphate, β-glycerophosphate, L-α-glycerophosphorylcholine, choline base, uridine-5′-monophosphate (UMP), adenosine-5′-monophosphate (AMP), and cytidine-5′-monophosphate (CMP).