An alginate lysate from Azotobacter vinelandii phage.

The alginate depolymerase associated with bacteriophage infection of Azotobacter vinelandii has been used in the analysis of sodium alginate. The enzyme degraded the polysaccharide to a series of oligouronides each containing a terminal 4-deoxy-alpha-L-erythro-hex-4-enopyranuronosyl residue. Analysis of these oligouronides, together with kinetic information, indicated that the enzyme was specific for mannuronic acid-containing regions of the polyuronide. The specificity of the enzyme made it possible to determine the primary structure of the macro-molecule. The phage-induced enzyme was shown to be distinct from the alginate lyase elaborated by the host organisms by its pH optimum, molecular weight, Michaelis constant and stability.