By the use of ion-exchange columns, a number of crude phosphopeptide fractions have been separated from pancreatic casein hydrolyzates. One of these fractions exhibits, to a remarkable degree, the property of sequestering calcium phosphate in the pH range from 7 to 10.5. Although numerous investigations have been made on phosphopeptides derived from casein by various enzymatic hydrolyses (1), no mention of this calcium phosphate sequestering property has been found in the literature.The finding of a casein fragment with the property of solubilizing calcium phosphate, or preventing its precipitation at relatively high pH's, has obvious implications in regard to an understanding of the role of casein in calcium and phosphate transport and assimilation. Apart from its interest in this connection, the phosphopeptide is of practical use in preventing the formation of calcium phosphate precipitates in culture media containing relatively high concentrations of phosphate and calcium ion.Eighteen grams of the calcium phosphate sequestering phosphopeptide were obtained from 2 lb of Trypticase, a pancreatic casein hydrolyzate (2). The Trypticase was dissolved in 18 lit. of a buffer containing 0.1M sodium acetate and 0.1M acetic acid. This solution was passed through a 4by 45-cm column of Dowex-l (Cl form, 50 to 100 mesh). The column was washed with 16 lit. of the same buffer until the free amino acids, neutral peptides, and the inorganic phosphate had been removed. Since these operations require several days for completion, they were conducted in a cold room to avoid micro-

The lipid from an anaerobic organism provisionally designated Bacteroides symbiosus was found to contain D-galactose. Alkaline hydrolysis of the lipid yielded a new glycerol galactoside, specific rotation -73°, with a crystalline hexabenzoate, mp 133-134°, specific rotation -6°. The properties of the new galactoside indicate it to be a 1-glycerol ß-D-galactofuranoside. This appears to be the first recorded recognition of a naturally occurring galactofuranoside.An anaerobic organism provisionally designated Bacteroides symbiosus is consumed in quantity by Entamoeba histolytica during amebal growth in the Shaffer-Frye culture systems (Shaffer, 1952;Reeves et al., 1957). Our interest in determining the lipid requirements for amebal growth led to a study of the composition of the bacterial lipid. This report deals with the finding of a new glycerol galactoside in the lipid.

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