glycosaminoglycans between the cell and the medium fractions; the cell fraction was composed of 60% chondroitin 4-sulphate, 5.5% chondrotin 6-sulphate, 16.8% dermatan sulphate and 13.9% heparan sulphate, whereas the medium fraction consisted of 24.5% chondroitin 4-sulphate, 28.2% chondroitin 6-sulphate, 33.7% dermatan sulphate and 10% heparan sulphate. Oversulphated chondroitin sulphate and oversulphated dermatan sulphate were found in the cell, cell-surface and medium fractions. On the basis of enzymic assays with chondro-4-sulphatase and chondro-6-sulphatase, the positions of sulphation in the disulphated disaccharides were identified as 4-and 6-positions of N-acetylgalactosamine. Most of the 35S-labelled glycosaminoglycans synthesized in peripheral PMN leucocytes were retained within cells, whereas those in peritoneal PMN leucocytes were secreted into the culture medium. Moreover, the amount of glycosaminoglycans in peritoneal PMN leucocytes was significantly less than that in peripheral PMN leucocytes. Assay of lysosomal enzymes showed that these activities in peritoneal PMN leucocytes were 2-fold higher than those in peripheral PMN leucocytes.

A partially purified fatty acid synthetase from Candida utilis synthesized fatty acids with varying chain lengths that depended on the assay temperature; the stearate/palmitate ratio decreased with decreasing temperature. This temperature-dependency was also observed in vivo for the newly synthesized fatty acids in cells incubated at various temperatures, although to a lesser extent than that observed in vitro. The difference in the temperature-dependencies observed in vivo and in vitro appeared to be due to the difference in the acceptors used in in vitro assays; a temperature-dependency comparable to that observed in vivo was reproduced in vitro on using microsomes rather than bovine serum albumin as the acceptor of the fatty acid synthetase products. Thus, the fatty acid synthetase was identified as a thermoreceptor in Candida cells known to possess a temperature-dependent, inducible desaturase system.

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