Glycosidase and lectins both bind sugars, but only the glycosidases have catalytic activity. The glycosidases occur among over 100 evolved protein families and Family 18 is one of the two chitinases (EC 3, 2.1.14) families. Interestingly, lectins are also in this evolutionary group of Family 18 glycosidase proteins. The proteins belonging to the enzymatically inactive class are referred to as c...

Remerciements La première personne que je souhaite remercier est évidemment mon cher promoteur, Yves Félix. C'est grâce à sa patience et à sa vision que j'ai appris et apprécié le monde de la topologie algébrique. Une autre personne qui a joué un rôle important dans mon éducation mathématique est certainement Pascal Lambrechts, qui mérite toute ma gratitude pour m'avoir enseigné tellement de ch...

α/β titanium alloys are choice materials for aeronautical and automotive industries due to their high performance to density ratio. For several applications, fatigue resistance is one of the critical design parameter. Particularly, initiation of fatigue crack plays a key role. Furthermore, hardly anything can be found in the literature on the fatigue crack initiation in multiphase microstructur...

Diese Dissertation wurde selbstständig, ohne unerlaubte Hilfe erarbeitet. III "Discovery consists of seeing what everybody has seen and thinking what nobody has thought." Acknowledgements I would like to gratefully acknowledge the enthusiastic supervision of Dr. Claudia Petritsch during this work. I thank her for offering such an interesting subject, for constant support and encouragement and f...

Intercellular signaling is crucial for embryonic patterning, cell specification and tissue induction. Hedgehog (Hh) encodes a secreted signal originally identified in Drosophila (Nüsslein-Volhard and Wieschaus, 1980). Vertebrate family members have been subsequently isolated (Echelard et al., 1993; Ekker et al., 1995; Krauss et al., 1993; Riddle et al., 1993; Roelink et al., 1994). In vivo and ...