期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1982
卷号:79
期号:24
页码:7739-7743
DOI:10.1073/pnas.79.24.7739
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Reconstruction of the sperm whale myoglobin structure was accomplished by a series of aqueous condensations of suitably protected synthetic myoglobin fragments to a large fragment prepared from the native protein. Reaction of N alpha,N epsilon 19-acetimidomyoglobin with 3-bromo-2-(2-nitrophenylsulfenyl)skatole (BNPS-skatole) yielded the fragment corresponding to residues 15-153. The covalent structure was reformed by sequential coupling of the N-hydroxysuccinimide esters of o-nitrophenylsulfenyl-L-tryptophan (residue 14) and selectively protected peptides corresponding to residues 1-5 and 6-13, which were synthesized by the solid-phase method and removed from the resin by methoxide-catalyzed methanolysis. A mixed aqueous solvent system containing methanol and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine/trifluoroacetic acid buffer (Quadrol) solubilized the peptide and protein fragments during the condensations. Replacement of the heme moiety and immunoaffinity chromatography made possible the isolation and purification of the reconstructed native molecule. The development of this nondestructive synthetic procedure allows investigation of the structural and functional significance of individual residues by isotopic enrichment or selective amino acid substitutions.