On the ampholytic nature of phospholipins

Abstract

Of the N-containing phospholipins (Levene and Rolf, 1921; McLean and McLean, 1927; Thierfelder and Klenk, 1930; Magistris, 1931, Robison, 1932; Klenk, 1933) at present three groups have been fairly accurately defined and isolated in an almost pure state:— O= Ρ—O. diglyceride O= Ρ—O. diglyceride O= Ρ—O. (fatty acid) sphingosine O= Ρ —O. choline O= Ρ—O. colamine O=Ρ —O. choline O= Ρ —OH O= Ρ—OH O= Ρ—OH I II III Lecithin Cephalin Sphingomyelin These compounds are diesters of phosphoric acid. One acid group is esterified with an alcoholic base which may be either colamine (aminoethylalcohol NH 2 . CH 2 . CH 2 . OH) or the corresponding quaternary ammonium base choline (OHN(CH 2 ) 3 . CH 2 . CH 2 . OH). The second acid group is linked in the sphingomyelin with sphingosine, the amino group of which is substituted by a fatty acid radical, or in lecithin and cephalin with a diglyceride. The analogous compounds lysolecithin and lysocephalin contain a monoglyceride instead of a diglyceride.

The Composition of Human Gallbladder Bile and Its Relationship to Cholelithiasis

“…The undetermined anion, as already indicated, is made up chiefly of bile acids other than cholic acid, although certain phospholipids may bind a portion of the base represented in this fraction. Inorganic (27); Chain and Kemp (28) ; Jukes (29) ), it is not permissible to assign to the phosphorus of bile the acidifying action observed. Likewise, it appears improbable that bile protein would possess the powerful acidifying action implied by Aronsohn and Andrews.…”