The evolutionary history of sialylation - Perspectives from fish genomes Dissertation Zur Erlangung des Doktorgrades der Naturwissenschaften -Dr. rer. nat.- vorgelegt dem Promotionsausschuss des Fachbereichs 2 (Biologie und Chemie) der Universität Bremen von Friederike Lehmann Universität Bremen 2004 The evolutionary history of sialylation - Perspectives from fish genomes Dissertation Zur Erlangung des Doktorgrades der Naturwissenschaften -Dr. rer. nat.- vorgelegt dem Promotionsausschuss des Fachbereichs 2 (Biologie und Chemie) der Universität Bremen von Friederike Lehmann 1. Gutachter: Prof. Dr. Sørge Kelm 2. Gutachterin: Prof. Dr. Rita Gerardy-Schahn Universität Bremen 2004 Statement of Originality I declare that this thesis has not been submitted in any form for another degree at any other university. The material discussed in this thesis is my own work, unless otherwise stated. Information derived from the literature or unpublished work of others has been acknowledged in the text and a list of references is provided. Friederike Lehmann Bremen, 25.06.2004 Table of Contents 1 INTRODUCTION ................................................................................. 1 1.1 Sialic acids .............................................................................................. 1 Structural diversity of sialic acids ...............................................................