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Extracts were prepared from liver stored at -65°C and from cultured fibroblasts as previously described [ 11. Sucrose density isoelectrofocusing at 400 V for 18 h, DEAE-cellulose chromatography using 10 mmol/l phosphate buffer, pH 6.5, and Sephadex gel filtration with 10 mmol/l phosphate buffer, pH 6.5, containing 100 mmol/l NaCl were carried out [ 31. Carboxypeptidase A (CPA:l), carboxypeptidase B (CPB: 2), N-acetyl-P-D-glucosaminidase [ 31, cathepsin B [ 41 and protein [5] were estimated and kinetic parameters determined as previously described.

Samples of vinylated cotton slivers with DS (degree of substitution) values of about 0.05 and below were found to be soluble in cupriethylenediamine hydroxide solution. Vis cosity determinations indicated D.P.'s of 97 to 586 which were considerably lower than that of the starting cotton (about 3000). Samples with higher D.S. values were all insoluhle in the reagent indicating at least a small amount of cross-linking. X-ray diffraction patterns made from the vinylated cotton slivers and cloth showed a nearly complete loss of cellulose crystallinity at D.S. values above about 0.10. This indicates good penetration of the crystalline regions by the catalyst and acetylene in the vinylation reaction. Good crease recovery angles were obtained by heating a sample of vinylated cotton print cloth ( D.S. = 0.21 ) with acidic catalysts. Most samples had breaking strength measurements 55-85% of the control cloth and showed 20-50% elongation at break.

Enzyme activity against hippuryl-L-arginine was studied in cultured skin fibroblasts from controls and cystic fibrosis patients. The enzyme had a lysosomal distribution and an acid optimum of pH 4.5 with little or no activity present above pH 7.0. Dithiothreitol was required for full activity and the kinetics of thiol activation were different for the control and cystic fibrosis enzyme. The properties and lysosomal distribution of the enzyme indicated that it was a carboxypeptidase B. Substrate affinity, thermolability, pH stability, the fall and rise in activity with subculture, the cyclical pattern of activity through serial passage and the level of activity were similar for the control and cystic fibrosis enzyme.