Biol. Pharm. Bull. 28(1) 13—18 (2005)

widely distributed in fish eggs, and share the feature of conserved motif and domain structure. We have purified several RBLs using sequential chromatographies of DEAE ionexchange and D-galactose affinity columns. Most RBLs, which were prepared from the adsorbed fraction (GSA) on a D-galactose-Sepharose column, have hemagglutinating activity for intact rabbit erythrocytes and human type B erythrocytes. In the screening of the hemagglutinating activity of fractions obtained from each purification step of carp (Cyprinus capio) egg RBL, distinct hemagglutinating activities were detected in not only the passed through fraction (GSNA) but also GSA on D-galactose-Sepharose. GSA contained RBL similarly to that from Silurus asotus and Osmerus lanceolatus, and showed hemagglutinating activity for intact human type B erythrocytes. On the other hand, GSNA showed activity for glutaraldehyde-fixed, trypsinized erythrocytes (GFTE). Folding or bending of DNA is a very crucial and essential biological event for the existence of cells. In eukaryotic cells, nucleohistone and some types of scaffold proteins take part in this event, while HU proteins are also involved in bacteria. DNA-binding proteins are known to be relevant to the characteristic architecture of kinetoplast DNA, that is composed of a tightly packed minicircle DNA network. Changing or keeping the topology of DNA is involved in the physiological functions of replication, repair, and packaging. In particular, an ATP-dependent DNA aggregating protein was isolated from rat liver, and identified to be serum albumin. Since GSNA from C. capio eggs aggregates DNA, we report here about the DNA aggregating protein (DAP) in a sequence-independent manner.