Zymolyase®, produced by a submerged culture of Arthrobacter luteus, has strong lytic activity against living yeast cell walls and can therefore be used to produce protoplasts or spheroplasts of various strains. An essential enzyme for the lytic activity of Zymolyase is beta-1,3-glucan laminaripentaohydrolase. It hydrolyzes linear glucose polymers at beta-1,3-linkages and releases specifically laminaripentaose as the main and minimum product unit. Zymolyase-20T is an ammonium sulfate precipitate with a lytic activity of 20,000 units/g. Zymolyase-100T is purified by affinity chromatography and has a lytic activity of 100,000 units/g. Lytic activity varies depending on yeast strain, growth stage of yeast, and culture conditions.