Ribeiro J M, Schneider M, Guimarães J A
Department of Entomology, University of Arizona, Tucson 85721, USA.
Biochem J. 1995 May 15;308 ( Pt 1)(Pt 1):243-9. doi: 10.1042/bj3080243.
The salivary anticoagulant of the blood-sucking bug Rhodnius prolixus was purified to homogeneity using a protocol consisting of weak cation-exchange, DEAE, hydrophobic-interaction and octadecyl reverse-phase chromatography, yielding a protein with the same N-terminal sequence as nitrophorin 2, one of the four NO haem protein carriers present in the salivary glands of Rhodnius with a molecular mass of 19689 Da [D. Champagne, R.H. Nussenzveig and J.M.C. Ribeiro, (1995) J. Biol. Chem. 270, in the press]. To exclude the possibility of the nitrophorin being a contaminant, another chromatographic protocol was performed, consisting of chromatofocusing followed by strong-cation-exchange chromatography. Again the anticoagulant was eluted with nitrophorin 2. Nitrophorin 2 inhibits coagulation Factor VIII-mediated activation of Factor X and accounts for all the anti-clotting activity observed in Rhodnius salivary glands.
利用由弱阳离子交换、二乙氨基乙基（DEAE）、疏水相互作用和十八烷基反相色谱组成的方案，将吸血臭虫罗阿丝虫的唾液抗凝血剂纯化至同质，得到一种蛋白质，其N端序列与亲硝蛋白2相同，亲硝蛋白2是罗阿丝虫唾液腺中存在的四种一氧化氮血红素蛋白载体之一，分子量为19689道尔顿[D. 香槟、R.H. 努森兹韦格和J.M.C. 里贝罗，（1995年）《生物化学杂志》270卷，即将发表]。为排除亲硝蛋白作为污染物的可能性，进行了另一种色谱方案，包括聚焦色谱，然后是强阳离子交换色谱。抗凝血剂再次与亲硝蛋白2一起洗脱。亲硝蛋白2抑制凝血因子VIII介导的因子X激活，并解释了在罗阿丝虫唾液腺中观察到的所有抗凝血活性。
