Chen T M, Ackermann B L, Coutant J E, Berman J M, Pelton J T
Merrell Dow Research Institute, Cincinnati, Ohio 45215.
Biomed Environ Mass Spectrom. 1989 Jan;18(1):12-9. doi: 10.1002/bms.1200180104.
The use of high-performance liquid chromatography and fast atom bombardment mass spectrometry are shown to be an efficient combination for investigating protease-mediated digestion of synthetic analogs of the peptide hormone ANF (atrial natriuretic factor). As examples of the reported methodology, rANF5-23-NH2 and rANF7-23-NH2 were digested with the endopeptidase thermolysin. These truncated analogs were selected to investigate metabolism within the disulfide-linked core of ANF, particularly at the Cys7-Phe8 bond. While this position was the site of initial hydrolysis for rANF5-23-NH2 (t1/2 = 0.5 min), the Cys7-Phe8 bond remained intact for all observed degradation products of rANF7-23-NH2 (t1/2 = 16 min). These findings suggest that improved stability towards endopeptidase-mediated core hydrolysis may be conferred to analogs of ANF by removal of the first six residues from the N-terminus.
高效液相色谱法和快原子轰击质谱法的联用被证明是研究肽激素心房钠尿肽（ANF）合成类似物的蛋白酶介导消化的有效组合。作为所报道方法的示例，用内肽酶嗜热菌蛋白酶消化rANF5-23-NH2和rANF7-23-NH2。选择这些截短的类似物来研究ANF二硫键连接核心内的代谢，特别是在Cys7-Phe8键处。虽然该位置是rANF5-23-NH2初始水解的位点（t1/2 = 0.5分钟），但对于rANF7-23-NH2的所有观察到的降解产物，Cys7-Phe8键保持完整（t1/2 = 16分钟）。这些发现表明，通过从N端去除前六个残基，ANF类似物对内肽酶介导的核心水解的稳定性可能会提高。
