ISSN:
1432-1432
Keywords:
Analogies
;
Ordered secondary structures
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 51 polypeptides of known 3-dimensional structures have been submitted to a search for internal similarities. It is shown that the frequency of proteins displaying significant amounts of internal similarities is higher than predicted by chance. A non-negligeable part of those similarities probably occurs in connection with the existence of ordered secondary structures. Indeed, similarity occurs at a much more important rate when analyses are restricted to protein subsequences corresponding to α helices or β pleated sheets. Furthermore, the correlation existing between the rates at which linear and inverted repeats occur inside protein subregions of ordered secondary structures suggests that a significant part of short similarities are analogies rather than homologies. An hypothesis is put forward suggesting that the regular alternations of hydrophobicity which characterize most of α helices and β strands could provoke the occurrence of significant amounts of similarities inside protein sequences.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02101639
