Sulphation by cultured cells. Cysteine, cysteinesulphinic acid and sulphite as sources for proteoglycan sulphate.
Bovine aortic smooth-muscle cells, bovine aortic endothelial cells, and IMR-90 human embryonic lung fibroblasts were tested to determine their ability to use cysteine or cysteine metabolites as a source of sulphate (SO4). Cells were incubated in SO4-depleted medium containing [3H]glucosamine plus 0.2 mM-cystine, 0.3 mM-cysteinesulphinic acid or 0.3 mM-sulphite (SO3). The [3H]chondroitin sulphate produced by the different cells was found to vary considerably in degree of sulphation under these conditions. One line of smooth-muscle cells utilized cysteine effectively as a SO4 source and thus produced chondroitin sulphate which was highly sulphated. IMR-90 fibroblasts produced partly sulphated chondroitin sulphate under these conditions, while another smooth-muscle cell line could not utilize cysteine, but could utilize cysteinesulphinic acid as a partial SO4 source. In contrast with the above cells, endothelial cells could not use cysteine or cysteinesulphinic acid as a source of SO4 and produced chondroitin with almost no SO4. All of the cells were able to utilize SO3. Incubation of the cells in the SO4-depleted medium containing [35S]cysteine confirmed that only the first line of smooth-muscle cells could convert significant amounts of [35S]cysteine to 35SO4. Furthermore, the addition of 0.4 mM inorganic SO4 did not inhibit the production of SO4 from cysteine by these cells.
D002478:Cells, Cultured; D002807:Chondroitin / Q000031:analogs & derivatives*; D002809:Chondroitin Sulfates / Q000096:biosynthesis*; D002854:Chromatography, Paper; D003545:Cysteine / Q000031:analogs & derivatives / Q000378:metabolism*; D004187:Disaccharides / Q000032:analysis; D004586:Electrophoresis; D018377:Neurotransmitter Agents; D013447:Sulfites / Q000378:metabolism*; D013462:Sulfur Radioisotopes; D014316:Tritium
D004187:Disaccharides; D018377:Neurotransmitter Agents; D013447:Sulfites; D013462:Sulfur Radioisotopes; D014316:Tritium; D002807:Chondroitin; D002809:Chondroitin Sulfates; D003545:Cysteine; C013461:cysteine sulfinic acid