PURIFICATION AND CHARACTERIZATION OF 5 CUTICULAR PROTEINS FROM THE SPIDER ARANEUS-DIADEMATUS

Urea-extractable proteins have been purified from the cephalothoracic cuticle of mature Araneus diadematus spiders, Two-dimensional gel elec trophoresis showed at least 12 major proteins, with pIs between 4.5 an d 8.5. Five proteins were purified and their primary structure determi ned, using a combination of mass spectrometry and Edman degradation, B ased on the amino acid sequence the proteins can be divided into two g roups, both characterized by hydrophobic regions dominated by Ala, Pro and Val. Sequence similarity was observed between all the spider cuti cle proteins and a number of proteins from other arthropod cuticles. A lthough the similarity seemed to be confined only to a region in the c entral part of the molecules, it does link these very distantly relate d species. Copyright (C) 1996 Elsevier Science Ltd