Enzymes specific for the κ and λ fractions of carrageenan were obtained from the cell-free culture medium of Pseudomonas carrageenovora. These enzymes were concentrated by precipitation with ammonium sulfate and separated by chromatography on hydroxylapatite.The κ-carrageenase was purified to electrophoretic homogeneity by incubation at 35 °C and chromatography on DEAE cellulose. The enzymic hydrolysis of κ-carrageenan was accompanied by a rapid fall in specific viscosity and increase in reducing power. The products were a homologous series of sulfated oligosaccharides with 3-O-(3,6-anhydro-α-D-galactopyranosyl)-D-galactopyranose-4-O-sulfate (neocarrabiose-4-O-sulfate) as the major degradation product, and an enzyme-resistant fraction. The alkali-modified enzyme-resistant fraction was degraded by the κ-carrageenase.

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Influx and efflux of anions in leaves of Elodea canadensis were investigated. A major component of phosphate efflux was found to be a function of the external phosphate concentration in accord with saturation kinetics, i.e. it was found to be proportional to phosphate influx. This suggests that the transport structures which mediate ion transport in plant membranes are mobile and can work in both directions (Fig. 7C). The higher the external concentration the more bound ions (A b (-) , Fig. 7C) are exchanged for external ions (A a (-) ) instead of being transported back to the inside of the membrane. Thus it was demonstrated that ion transport in plants is mediated by carriers or transportases. The action of the carriers is supported by ATP or another "energy-rich" compound which is regenerated by ATP; ATP may be supplied by the mitochondria or/and chloroplasts. In line with these findings some transport phenomena exhibited features of coenzyme kinetics.Magnitude and molecular nature of the carrier motion are unknown. There is no evidence for rotating or shuttling monovalent carriers. The carriers may be polyvalent and may be part of bigger structural units within the membrane. Nevertheless, these experimental observations are rather consistent with the idea that plant membranes contain tertiary or quarternary formed proteins or lipoproteins than with the conventional lipid bilayer models of cell membranes.

The proteolytic enzymes from the sterile secretion of the pitchers of 3 Nepenthes species were purified to electrophoretic homogenity by chromatography on Ecteola cellulose. The properties of the purified enzymes were investigated.