On the supersecondary structure of acid proteases
Andreeva, N.S.; Gustchina, A.E.
Biochemical and Biophysical Research Communications 87(1): 32-42
1979
ISSN/ISBN: 0006-291X PMID: 36889 Document Number: 144537
Polypeptide chains of porcine pepsin molecules and mold acid proteases consist of 4 topologically equivalent structural units. Each pair of units forms a domain. The symmetrical packing of 2 units within each domain is the important structural feature of acid proteases. Although the primary structures of the 4 structural units are in general not homologous there are close similarities of the sequences of some topologically equivalent elements. These data are considered as the development of the idea on gene duplications and the subsequent fusion during evolution of acid proteases.