This is an application to continue investigation of the biochemistry, biosynthesis and intermediary metabolism of human lenticular sphingolipids. The proposal is modified to include the following: 1. Reduce the specific aims of the project with less emphasis on ceramide metabolism. 2. Concentrate on the novel finding of lenticular fucolipids. 3. Publish more papers. The research plan can be summarized as follows: 1. Composition and complete characterization of human lenticular fucolipids: determination of the fucolipid contents between normal and cataractous lenses; lenkage and anomerity studies of the fucolipid structures by combined chemical, enzymatic, and gasliquid chromatographic techniques. 2. Immunological properties of the purified fucolipids: determinations of blood group A, B, H, Le(a) and Le(b) activities of the isolated fucolipids before and after sialidase treatment of the intact lipid. 3. Enzymatic synthesis of fucoglycolipid by an Alpha-fucosyltransferase from human lens: development of assay system to demonstrate the biosynthesis in vitro of focogangliosides by enzyme preparations isolated from human lenses. 4. Glycosphingolipid: sialyltransferase activity of human lenses: development of assay system to show the biosynthesis in vitro of fucogangliosides by enzyme fractions obtained from human lenses. It is hoped that these studies will provide new information for the understanding of the process of cataractogenesis from an area of research (glycosphingolipids and glycosphingolipid enzymology) which has never been explored in depth before.
