Purification and Analysis of Amino Acid Sequences of Pulmonary Surfactant Proteins

ABSTRACT

PURPOSE: For the synthesis of surfactant protein(SP) peptides and production of next generation artificial pulmonary surfactant(PS), we have isolated SP-B, C from bovine PS, and studied the biochemical properties and amino acid sequences of these protein-peptides. METHODS: Crude surfactant and purified surfactant were isolated from materials extracted from the bovine lung lavage. The hydrophobic SP-B, C were purified by Sephadex LH 60 column chromatography from PS. The purities of SP-B, C were assessed by tricine buffer SDS-polyacrylamide gel electrophoresis and the amino acid sequences of these proteins were determined using Beckman PI-2090. RESULTS: The molecular weights of SP-B, C shown in SDS-polyacrylamide gel electrophoresis were as follows; 15,000-18,000(oligomer) Da for SP-B, 3,500-5,000 Da for SP-C. The amino acid sequences were; FPIPLPYCWL LRTLIKKIQA VIPKGVLAMT VAQCHVVPL LVGGIQQLV IEYSVILLTD TLLGRLPNLV CGLRLRCSG in SP-B, LIPCCPVNIK RLLIVVVVVV LLVVVIVGAL LMGL in SP-C, respectively. These results indicated that the amino acid sequences of bovine SPs were different. CONCLUSION: The SP-B, C were purified from bovine PS, and amino acid sequences of SP-B, C were determined. Further studies are needed for the development and use of next generations of exogenous PS preparation based on synthetic SP-peptides for the treatment of neonatal RDS in the future.