. The Biological bulletin. Biology; Zoology; Marine biology. 194 JULIAN B. AIARSH (1957), total lipid determinations were made by the method of Marsh and Wein- stein (1966), using tristearin as a standard. Protein was measured by the Lowry method (1951) with bovine plasma albumin as a standard. Phospholipids were determined by Bartlett's method (1959) and chromatography of the phospholipid fraction was carried out as described by Abramson and Blecher (1964). Total protein-bound carbohydrate was measured on the lipid-free protein after washing the precipitate with cold 5% trichloroacetic acid t
. The Biological bulletin. Biology; Zoology; Marine biology. 194 JULIAN B. AIARSH (1957), total lipid determinations were made by the method of Marsh and Wein- stein (1966), using tristearin as a standard. Protein was measured by the Lowry method (1951) with bovine plasma albumin as a standard. Phospholipids were determined by Bartlett's method (1959) and chromatography of the phospholipid fraction was carried out as described by Abramson and Blecher (1964). Total protein-bound carbohydrate was measured on the lipid-free protein after washing the precipitate with cold 5% trichloroacetic acid to remove chloride ions. The protein precipitate was then heated for 2 hours at 100° in 1 N HoSO^ and the carbohydrate content of the extract measured by the anthrone method (Ashwell. 1957) using galactose as a standard. Additional extraction of the precipitate or treatment with 2 N HCl for 3 hours at 100° did not significantly increase the carbohydrate yield. The neutral carbohydrate fraction contained 96% mannose and 4% arabinose as determined by gas-liquid chromatography of the alcohol hexacetates (Sawardeker, Sloneker and Jeanes, 1965). The amino acid com- position of the delipidized protein was measured with an amino acid analyzer. Figure 1. Sedimentation of Arbacia egg low density lipoprotein in NaBr, pH 6, at 42,040 rpm. Sedimentation is from right to left, the interval between pictures is 4 minutes, and the bar angle 60°. after hydrolysis in 6 N HCl for 23 hours at 110° in a sealed tube. Tryptophan was determined colorimetrically (Opienska-Blauth. Charezinski and Berbec. 1963) on a solution of the delipidized protein in N NaOH. The fatty acid composi- tion of the lipid moiety was determined by gas-liquid chromatography of the methyl esters after saponification in methanolic KOH (James, 1960). Identifica- tion of the acids was made by comparison of the retention times with known standards. Free and esterified cholesterol was measured by the method of Sperry
Size: 2716px × 920px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectb, booksubjectzoology
