Structural transition of alpha 1-antitrypsin by a peptide sequentially similar to beta-strand s4A.
Crystal structure studies have shown that cleaved and intact serpins differ essentially in the topology of beta-sheet A. This is five-stranded in the intact molecules and six-stranded after cleavage by insertion of strand s4A whose C-terminus has become free [Löbermann, H., Tokuoka, R., Deisenhofer, J. & Huber, R. (1984) J. Mol. Biol. 177, 531-556; Wright, T. H., Qian, H. X. & Huber, R. (1990) J. Mol. Biol. 213, 513-528]. The structural transition is accompanied by changes in spectral properties and an increase in thermal stability. We show here that an N alpha-acetyl-tetradecapeptide with the amino acid sequence of strand s4A, residues 345-358 of human alpha 1-antitrypsin, associates with intact alpha 1-antitrypsin and forms a stoichiometric complex with properties very similar to cleaved alpha 1-antitrypsin. Complex generation has the characteristics of a folding process.
Schulze
A J
AJ
Max-Planck-Institut für Biochemie, Martinsried, Federal Republic of Germany.
Baumann
U
U
Knof
S
S
Jaeger
E
E
Huber
R
R
Laurell
C B
CB
D000595:Amino Acid Sequence; D002942:Circular Dichroism; D006801:Humans; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D000515:alpha 1-Antitrypsin / Q000378:metabolism / Q000648:ultrastructure*
D010446:Peptide Fragments; D000515:alpha 1-Antitrypsin