Cellophane membranes in growth of L variants of the genus Proteus.

A cellophane membrane has proved a simple device for separating the L variant of Streptobacillus moniliformis from the bacterial form, as reported by P6rezMiravete and Calder6n (1956). When a culture was inoculated on cellophane resting on clear medium, they observed the development of the L type colonies only on the agar, whereas bacterial growth flourished on the surface of the cellophane. It was apparent that growth factors had passed through the membrane to the bacteria and that the L form of the organism had selectively filtered through the pores of the cellophane. A similar procedure proved expedient for the study of the L variant colonies of the genus Proteus.