Alginate lyase releases cell-bound lipase from mucoid strains of Pseudomonas aeruginosa.

Alginate lyase (EC 4.2.2.3) was partially purified from the culture medium of Bacillus circulans JBH2 by ammonium sulphate precipitation, gel filtration and ion-exchange chromatography. The purified enzyme was unstable in the absence of protecting substances such as gelatin. At a pH optimum of 5.8, the enzyme depolymerized algal as well as bacterial alginates, the latter in the deacetylated form more effectively than in the acetylated form. Incubation of various mucoid strains of Pseudomonas aeruginosa in the presence of purified alginate lyase caused rapid degradation of the alginate slime without killing the cells. The degradation of alginate was accompanied by a release of cell-bound lipase into the medium indicating that one of the functions of the alginate layer of mucoid bacteria might be to serve as a temporary reservoir for lipase.