Comp. Biochem. Physiol, Vol. 77B, No. 4, pp. 721-727, 1984 0305-0491/84 $3.00 + 0.00 Printed in Great Britain © 1984 Pergamon Press Ltd CHARACTERIZATION OF THE CARBOHYDRATE SPECIFICITY OF SERUM LECTINS FROM THE SCORPION HADRURUS ARIZONENSIS STAHNKE GERARDO R. VASTA* and ELIAS COHENt *Department of Biochemistry, Medical University of South Carolina, 171 Ashley Avenue, Charleston, SC 29425, U.S.A. Telephone (803) 792-4321 and tRoswell Park Memorial Institute, Department of Laboratory Medicine, 666 Elm Street, Buffalo, NY 14263, USA (Received 18 July 1983) Abstract--1. Hadrurus arizonensis serum lectins were found to be heterogeneous in specificity but all fractions bound sialoconjugates bearing terminal oligosaccharides NANA(NGNA)-ct-2-3(6)Gal- and NAN(NGNA)-ct-2-6-GalNAc. 2. The oligosaccharide NANA-~-2-8-NANA- from colominic acid was not recognized by any of H. arizonensis lectin fractions. 3. No galactosyl-bindinglectins were detected in H. arizonensis, but were earlier observed in scorpions Androctonus australis and Centruroides sculpturatus, from the Buthidae family. 4. In this respect the serological behaviour of H. arizonensis lectin was similar to those from other American Vaejovidae species studied previously: Vaejovis spinigerus and Paruroetonus mesaensis. 5. These results and our former studies suggest that sialic acid-binding serum lectins are ubiquitous within the Chelicerata species studied so far. INTRODUCTION Lectins are non-immunoglobulin protein or gly- coprotein molecules present in microorganisms, plants, invertebrates and vertebrates which bind specifically to certain carbohydrate structures and are frequently detected by their capacity (if multivalent) to agglutinate cells. Variable numbers of species from invertebrate phyla have been examined for the pres- ence of lectins and results have shown that these substances are widely distributed (Gold and Balding, 1975). Much invertebrate lectin research was initially re- lated to human blood groups, and further efforts were directed towards the elucidation of their carbo- hydrate specificity and identification of the carbo- hydrate moieties to which they bind on the cell surface. The carbohydrate specificities of serum and tissue lectins of species from most invertebrate and lower chordate groups do not correlate with their taxonomical relationships; lectin specificities differ even within a particular genus and a good example are the tunicate serum lectins, which exhibit very diverse specificities even in closely related species (Vasta et al., 1982a). However, among all in- vertebrate phyla, the Chelicerata form a relatively homogenous group because all representatives studied so far have sialoconjugate-binding lectins in their serum (Vasta and Marchalonis, 1983). The specificity of an invertebrate agglutinin for sialic acid was initially described by Cohen in the serum of the horseshoe crab Lirnulus polyphernus (Cohen, 1968), an observation confirmed by Pardoe et al. (1970), and in studies with limulin, the purified lectin (Roche and Monsigny, 1979). Shimizu et al. (1977, 1979) demon- strated that some of the lectins of the Japanese horseshoe crab Tachypleus tridentatus show affinity for the N-acetylamino sugars, but the agglutinins are inhibited most effectively by glycoproteins that con- tain sialic acid. Bishayee and Dorai (1980) showed that serum lectins from the Indian horseshoe crab Carcinoscorpius rotundicauda are specific for sialo- conjugates. Brahmi and Cooper (1974) described natural hemagglutinins and some aspects of cellular immunity in the Algerian scorpion Androctonus aus- tralis, in addition, Cohen et al. (1979) and Vasta et al. (1982b) studied the specificity of A. australis hemolymph agglutinins and their ability of differentiating between normal and chronic leukemia lymphocytes. In further studies we found sialic-acid- binding lectins in the hemolymph of the American scorpions Centruroides sculpturatus (Vasta and Cohen, 1982), Paruroctonus mesaensis (Vasta and Cohen), Vaejovis spinigerus (Vasta and Cohen, b) and V. confuscius (Vasta and Cohen, c), the "whip scor- pion" Mastigoproctus giganteus (Vasta and Cohen, a) and American spiders of the genus Aphonopelma (Vasta and Cohen, d). In this report we describe the detection and charac- terization of the carbohydrate specificity of lectins present in the serum of the giant hairy scorpion Hadrurus arizonensis Stahnke (Vaejovidae) as a first stage of an ongoing project which includes their purification and physicochemical characterization. MATERIALS AND METHODS Collection of H. arizonensis specimens Two hundred and sixty-eight adult H. arizonensis (162 females and 106 males) were collected near Mesa, AZ, and bled from the pedipalps. Serum was pooled, cleared from clots and debris by centrifugation at 5000g for 15 min at 4°C, aliquoted and stored at -25°C until used. Limulus polyphemus serum was received as a courtesy of Dr J. 721