Lo T N, Cohen A B, James H L
Biochim Biophys Acta. 1976 Dec 22;453(2):345-56.
The products resulting from the interaction of alpha-1-antitrypsin with elastase were examined with polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate, and by affinity chromatography. Five products of the reaction can be identified by polyacrylamide disc gel electrophoresis. Two products are complexes between alpha-1-antitrypsin and elastase (73 800 and 58 300 daltons). Two additional products are identical to fragments of alpha-1-antitrypsin which can be washed from a column of Sepharose-bound elastase immediately after alpha-1-antitrypsin is applied to the column. The larger component about 50 000 daltons, reacts with antiserum to alpha-1-antitrypsin, and does not inhibit enzymes. Together, these two products have an amino acid analysis similar to alpha-1-antitrypsin. These two fragments are probably hydrolytic products of the interaction of elastase with alpha-1-antitrypsin which is biologically inactive. The fifth product is probably a fragment of alpha-1-antitrypsin missing from the low molecular weight complex. The components of the complexes can be separated from each other by a mild nucleophilic attack. Small quantities of alpha-1-antitrypsin can be displaced from the elastase affinity column by phenyl methane sulfonyl fluoride. In conclusion, porcine pancreatic elastase forms two complexes with alpha-1-antitrypsin. One or both complexes can be split by alkali.
在有和没有十二烷基硫酸钠存在的情况下，通过聚丙烯酰胺凝胶电泳以及亲和色谱法，对α-1-抗胰蛋白酶与弹性蛋白酶相互作用产生的产物进行了检测。通过聚丙烯酰胺圆盘凝胶电泳可鉴定出该反应的五种产物。两种产物是α-1-抗胰蛋白酶与弹性蛋白酶的复合物（73800和58300道尔顿）。另外两种产物与α-1-抗胰蛋白酶的片段相同，在将α-1-抗胰蛋白酶应用于琼脂糖结合弹性蛋白酶柱后，可立即从该柱上洗脱下来。较大的成分约50000道尔顿，能与抗α-1-抗胰蛋白酶血清发生反应，且不抑制酶。这两种产物一起进行氨基酸分析时，结果与α-1-抗胰蛋白酶相似。这两个片段可能是弹性蛋白酶与无生物活性的α-1-抗胰蛋白酶相互作用的水解产物。第五种产物可能是低分子量复合物中缺失的α-1-抗胰蛋白酶片段。通过温和的亲核攻击可将复合物的各成分彼此分离。少量的α-1-抗胰蛋白酶可被苯甲磺酰氟从弹性蛋白酶亲和柱上置换下来。总之，猪胰弹性蛋白酶与α-1-抗胰蛋白酶形成两种复合物。一种或两种复合物都可被碱裂解。
