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Human red blood cells (RBC), which are the cells most commonly used in the study of biological membranes, have some glycoproteins in their cell membrane. These membrane proteins are band 3 and glycophorins A–D, and some substoichiometric glycoproteins (e.g., CD44, CD47, Lu, Kell, Duffy). The oligosaccharide that band 3 contains has one N-linked oligosaccharide, and glycophorins possess mostly O-linked oligosaccharides. The end of the O-linked oligosaccharide is linked to sialic acid. In humans, this sialic acid is N-acetylneuraminic acid (NeuAc). Another sialic acid, N-glycolylneuraminic acid (NeuGc) is present in red blood cells of non-human origin. While the biological function of band 3 is well known as an anion exchanger, it has been suggested that the oligosaccharide of band 3 does not affect the anion transport function. Although band 3 has been studied in detail, the physiological functions of glycophorins remain unclear. This review mainly describes the sialo-oligosaccharide structures of band 3 and glycophorins, followed by a discussion of the physiological functions that have been reported in the literature to date. Moreover, other glycoproteins in red blood cell membranes of non-human origin are described, and the physiological function of glycophorin in carp red blood cell membranes is discussed with respect to its bacteriostatic activity.

P-Agarase was purified from the culture fluid of a porphyran-decomposing marine bacterium (strain AP-2) by ammonium sulfate precipitation, successive column chromatography and DNase and RNase treatment. The final enzyme preparation appeared to be homogeneous on polyacrylamide gel electrophoresis. The enzyme had a molecular mass of 20 kDa, a pH optimum of 5.5, and was stable in the pH region 4.0-9.0 and at temperatures below 45' C.The P-agarase was a novel endo-type enzyme which hydrolyzed neoagarotetraose, larger neoagarooligosaccharides and agar to give neoagarobiose [3,6-anhydro-a-~-galactopyranosyl-(l + 3)-u-galactose] as the predominant product, The enzyme did not act on K-carrageenan.According to the criteria of Bergey's Manual of Systematic Bacteriology, the strain was assigned to the genus Vibrio.Agar and porphyran, sulfated polysaccharides, are distributed in the cell wall of several species of red algae [I]. There have been some reports on agarases from agar-decomposing bacteria, especially on the extracellular fl-agarase from Cytophaga sp. and Pseudomonas atlantica [2 ~ 41. The enzymes from these microorganisms hydrolyzed agar and porphyran to give neoagarotetraose as the predominant product. The existence of another type of intracellular agarase (p-neoagarotetraose hydrolase or P-agarase 11) from P. atluntica was suggested by Morrice et al., but the properties or mechanism of action have not been fully investigated [3 -51.In a previous work, we isolated a porphyran-degrading bacterium (strain AP-2) from an alga [6]. The strain AP-2 produces three extracellular agarases. One of them hydrolyzes neoagarotetraose and larger saccharides to give neoagarobiose, whereas the other two agarases act on hexoses or larger saccharides in the same way as the known P-agarases [4, 71. This paper describes the purification and characterization of the novel P-agarase from the strain AP-2. MATERIALS AND METHODS OrganismThe organism (strain AP-2) was isolated from an alga collected in the coastal sea of the Fukuoka Prefecture of Japan in 1985 [6]. The organism was grown on a slant medium, pH 7.4, composed of 0.5% peptone, 0.1 % yeast extract, 0.2% porphyran, 3.0% NaCl and 1.5% agar, stored at 4'C in a

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lead to a high rate of cardiovascular mortality. In particular, multiple pathways including calcium and phosphorus metabolic abnormalities caused by secondary hyperparathyroidism, inflammation and cardiac overload accelerate the process of valvular calcification, and the consequent P atients with end-stage renal disease (ESRD) on chronic hemodialysis (HD) often have a high prevalence of structural abnormalities of the heart including calcified valvular sclerosis, 1,2 left ventricular (LV) remodeling 3,4 and LV diastolic dysfunction, 5 which may

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We isolated a high-purity carp glycophorin from carp erythrocyte membranes following extraction using the lithium diiodosalicylate (LIS)-phenol method and streptomycin treatment. The main carp glycophorin was observed to locate at the position of the carp and human band-3 proteins on an SDS-polyacrylamide gel. Only the N-glycolylneuraminic acid (NeuGc) form of sialic acid was detected in the carp glycophorin. The oligosaccharide fraction was separated into two components (P-1 and P-2) using a Glyco-Pak DEAE column. We observed bacteriostatic activity against five strains of bacteria, including two known fish pathogens. Fractions from the carp erythrocyte membrane, the glycophorin oligosaccharide and the P-1 also exhibited bacteriostatic activity; whereas the glycolipid fraction and the glycophorin fraction without sialic acid did not show the activity. The carp glycophorin molecules attach to the flagellum of V. anguillarum or the cell surface of M. luteus and inhibited bacterial growth.

Pyoderma gangrenosum presents with chronic skin ulcers and is histologically characterized by neutrophil infiltration throughout the dermis. It is also occasionally associated with ulcerative colitis, a type of inflammatory bowel disease, against which granulocyte and monocyte adsorption apheresis (GCAP) has recently shown remarkable efficacy. We performed GCAP on three refractory cases of pyoderma gangrenosum with painful bilateral leg ulcers and hereby report the results obtained. Patient 1 was a 43-year-old woman with a four-year history of recurrent painful skin ulcers treated with prednisolone and cyclosporine. Patient 2 was a 29-year-old woman who had been suffering from pyoderma gangrenosum with severe pain for two weeks, associated with an 11-year history of ulcerative colitis treated with prednisolone and salazosulfapyridine. Patient 3 was a 63-year-old man with a three-year history of recurrent ulcers with pain, suffering from rheumatoid arthritis treated with prednisolone and cyclophosphamide. The sizes of the lesions were reduced in all three patients following a weekly GCAP treatment for 10 or 11 consecutive weeks, and the re-epithelialization of ulcers were additionally observed in two patients. The pain disappeared dramatically in all three patients following two sessions of GCAP therapy. No adverse effects were observed for up to at least eight months after treatment. We therefore considered GCAP as one effective alternative to currently existing therapies, with regards to refractory cases of pyoderma gangrenosum.