June, 1948 PHOSPHORYLATION OF PROTEINS 2101 the methyl ester of e-carbobenzoxy-lysine yields on heating mainly e,c'-dicarbobenzoxy-lysine an-(6) This specificity contrasts with the non-specific action of other phosphorylating agents which are known to react with amines, guanidyl compounds, etc.. as well as with alcohols and phenols. Mayer and Heidelberger' phosphorylated horse-serum albumin in alkaline solution with phosphorus oxychloride. The derivatives contained 2 4 % phosphorus, approximately half of which was accounted for by reaction with the amino groups. The reaction of egg albumin under similar conditions was described by Heidelbuger, cf a1.a (7) Mayer and Heidelberger, TEIS JOURNAL, 68, 18 (1946). ( 8 ) Heidelberger, Davis and Treffus, ibid.. 611, 498 (1941).
The purpose of this work was to examine the influence of apolipoprotein gene variation on plasma lipid levels in a population of Mayan Indians of the Yucatan Peninsula, Mexico. Four restriction enzymes: XmnI, PstI, SstI, and PvuII, were used to detect restriction fragment length polymorphisms (RFLP) within the region of the apolipoprotein AI/CIII/AIV gene cluster. The frequencies of these polymorphisms in this Mayan population were similar to those reported for other Amerindian populations, but differed widely from those reported for Caucasian populations. The XmnI and SstI RFLPs were informative for association studies in this population, and we analyzed their influence on the quantitative variation of plasma cholesterol and triglycerides. Using a nonparametric analysis of variance, it is shown that the presence of the XmnI restriction site had a significant effect in lowering plasma cholesterol, whereas the presence of the restriction site for SstI had a significant effect in raising plasma triglycerides. Consequently, genetic indicators of both low and high risk for lipid-related diseases, such as atherosclerosis and coronary heart disease, seem to be present within the same gene region in this Mayan population.
Ion-exchange chromatography was used to follow changes in inositol phosphate esters of California small white beans and hard red winter wheat during autolysis and germination. Untreated bean extracts con-,tained appreciable quantities of lower phosphate esters, while wheat extracts contained only inositol hexaphosphate (IHP). Autolysis in beans at both 35 and 55°C was slow (30% of IHP still present after 48 hr). Over 80% of wheat IHP was hydrolyzed in 4 hr at both temperatures. During autolysis bean extracts contained appreciable quantities of lower phosphate esters while wheat chromatograms showed trace amounts. Germination of the seeds for 2,4 and 7 days produced similar patterns of change in the phosphate esters as in autolysis. The use of wheat phytase to rapidly reduce phytic acid in bean preparations is presented.
INDUSTRIALAND ENGINEERING CHEMISTRY tion, in order to lessen the superheating caused by a layer of insoluble material that formed on the evaporator.For further tests on this method of solubilization, samples of bark from salt-water-floated logs, fresh-water-floated logs, and bark peeled in the woods were obtained. Sulfited extracts were prepared from each sample. From the fresh-water-floated and woods-peeled bark, untreated.extracts were prepared for comparison. Liquors obtained by leaching were divided; half was sulfited and the other half reduced to extract without treatment. The analyses of these materials are given in Table III. All of the spent barks contained approximately the same amount of tannin in these experimen ts. The insolubles in an aqueous mixture containing 15% of extract from bark peeled in the woods amounted to 8%. Sulfiting reduced this to less than 1%. A similar mixture prepared from fresh-water-floated bark contained 13% insolubles, which was reduced to less than 1 % by the sulfite treatment. The sulfite treatment was equally effective in solubilizing tannin extract from ealt-water-floated bark, samples of which contained 20 to 40% insolubles without treatment (Table I). The purity of the sulfited extracts was comparable to that of woods-peeled-bark extracts. The addition of lactic or acetic acid to solutions of sulfited extracts did not cause precipitation.
ACKNOWLEDGMENTThe authors are indebted to Ray Hatch, Weyerhaeuser Timber Company, for providing the pictures and the bark; to the Worthington Pump and Machinery Corporation for the use of Stacom horn-angle hydraulic press; to M. J. Stacom, Worthington Pump and Machinery Corporation, for operating the press, and Charles H. Binkley of this Laboratory, for processing the bark; to Stephen N. Wyckoff, U. S. Forest Service, for permission to use the map showing the movement and concentration of hemlock logs in pulp manufacture.
simplify interpretation. A microorganism responding equally well to dl-and L-methionine might be helpful. This problem merits further investigation.
Stability of DL-Metbionine
Added to FeedsThe stability of DL-methionine in poultry diets has been investigated under several conditions, as shown in Table II. Broiler rations supplemented with 0.05 and 0.0625% DL-methionine were kept at room temperature for as long as 13 months without deterioration. In another experiment a commercial broiler mash containing 0.05% DLmethionine was stored for 14 months CEREAL COMPONENTS under the roof of a warehouse in different types of containers. During the summer months the heat in this warehouse occasionally reached 110°F. (43.3°C.), but no loss of added DL-methionine was noted.The effect of higher temperatures was also studied. For this purpose a commercial diet was supplemented with 0.05% DL-methionine and samples were subjected to temperatures up to 100°C. for varying periods of time. The results of this experiment, shown in Table II, indicate that when the diet was heated to 50°C. for 5 days, no loss of DLmethionine occurred. But when the temperature was raised to 100°C ., considerable loss took place after 3 days. As the diet itself became brown and decomposed, the loss of methionine is not surprising.
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