F. Bordusa, H.-D. Jakubke/Bioorg. Med. Chem. 6 (1998) 1775±1780
1779
0
0
contacts to the backbone of P1 and P2 amino acids,
unlike those known for type I serine proteases.32±34
Therefore, a high ¯exibility of these S0 subsite regions
could be postulated, as was also found for type II serine
proteases like subtilisin31 and in particular for cysteine
proteases.35±37
products using the software Hyperdata Chromsoft
(Vers. 2.15, Autochrom Inc., USA).
Acknowledgements
We gratefully appreciate the gift of prolyl endopeptidase
by Fluka Chemie AG, Buchs, Switzerland. Special
thanks are due to Dr. Peter Halling, Strathclyde Uni-
versity Glasgow, for reading and correcting the manu-
script. This work has been supported by the Deutsche
Forschungsgemeinschaft (Ja 559/9-1 and INK 23) and
Fond der Chemischen Industrie.
Experimental
Materials
PEP was obtained from Fluka Chemie AG, Buchs,
Switzerland. Bz-Gly-Pro-OMe and the corresponding
enantiomer were synthesized from Bz-Gly-OH and H-
Pro-OMe or H-d-Pro-OMe, respectively, by standard
procedures. H-b-Ala-NH2, H-Aze-NH2 and H-g-Abu-
NH2 were synthesized by amidation of the correspond-
ing methyl esters. The pentapeptides were synthesized as
described by Ullmann et al.35
References and Notes
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