Jang J S, Park D K, Chun M, Byun S M
Department of Agricultural Chemistry, Korea University, Seoul.
Biochim Biophys Acta. 1993 Mar 5;1162(1-2):233-5. doi: 10.1016/0167-4838(93)90154-j.
Ser-49 located at the exposed surface loop of subtilisin J was replaced with Asp and Arg. Proteinase activity of the Asp-49 mutant was similar to that of wild-type, but the Arg mutant was inactivated. At 37 degrees C, mature subtilisin J protein of the Asp-49 mutant rapidly degraded, and specific breakdown products were accumulated. These proteins were analyzed by SDS-PAGE, and the N-terminal sequences were determined for the mature and deleted protein. We identified the autoproteolytic cleavage site in the mature Asp-49 mutant protein from sequencing data.
位于枯草杆菌蛋白酶J暴露表面环上的丝氨酸-49被天冬氨酸和精氨酸取代。天冬氨酸-49突变体的蛋白酶活性与野生型相似，但精氨酸突变体失活。在37℃时，天冬氨酸-49突变体的成熟枯草杆菌蛋白酶J蛋白迅速降解，并积累了特定的降解产物。通过SDS-PAGE对这些蛋白质进行分析，并测定成熟蛋白和缺失蛋白的N端序列。我们从测序数据中确定了成熟天冬氨酸-49突变体蛋白中的自蛋白水解切割位点。
