Factors affecting Production of Cellulose at the Air/ Liquid Interface of a Culture of Acetobacter xylinum

SUMMARY: The cells in a developing culture of Acetobacter xylinum in a static liquid glucose medium were swept to the surface by the flotation of a submerged cellulose net. The net was probably pulled to the surface by adsorbed carbon dioxide given off by the metabolizing cells. The relatively high oxygen pressure at the aerated surface of a static liquid culture mediated the rapid production of cellulose in the surface layer. A. xylinum produced less cellulose in swirled than in static nutrient medium. Cellulose in the swirled medium occurred in the form of remarkable bodies, spherical, jointed or stellate in form, up to 10 mm. in size. The swirling favoured the overgrowth of the wild type organism by mutants which were specifically deficient in the ability to form cellulose. On the basis of the type of colonial growth and of the pellicle characteristics, two groups of A. xylinum mutants with an extreme deficiency in cellulose-forming ability and one with an intermediate degree of deficiency were differentiated.