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The transfer of methyl groups from methionine to choline and creatine has been demonstrated by the isolation of deuteriocholine and deuteriocreatine from the tissues, and of deutriocreatinine from the urine, or rats fed methionine containg a deuteriomethyl group. It was found from the deuterium ocntents of the isolated compounds that at the end of a given experimental period, each of the isolated compounds had derived approximately the same percentage of methyl groups from the deuteriomethionine of the diet. All the deuterium in the isolated choline was shown to be in the methyl grops. The concentraion of deuterium in the methyl gorups of the choline and creatine from the tissues as well as of the urinary creatinine rose to 85 per cent of that of the deuterio-methionine fed over a period of 14 weeks, strongly indicating that there was no other precursor of methyl groups in the diet employed. The transfer of methyl groups from choline to creatime has been demonstrated by the isolation of deuteriocreatime from the tissues and of deuteriocreattnine from the urine of rats maintained on a diet containing deuteriocholine and homocystine. Thus direct proof has been afforded to substantiate the hypothesis previously presentd that methionine may be a precursor of choline in so far as the methyl groups are concerned. The significance of these findings with regard to the prevention of fatty infiltraton of the liver and to the prevention of hemorrhagic kidneys resulting from a choline-deficient diet has been pointed out. The data support the hypothesis that the body is incapable of generationg methyl groups for certain methlations and that methyl groups must be supplied in the diet in a biologically labile from such as occurs in methionine and choline.

Preparations of human malignant effusion galactosyltransferase activity purified according to previously published techniques using enzyme-specific affinity chromatography consistently produced antibodies directed toward immunoglobulins with no detectable antigalactosyltransferase. Double immunodiffusion analysis of the antigen showed the presence of both IgG and IgA. Affinity chromatography with anti-human IgG-Sepharose and anti-human serum-Sepharose resulted in a 48,000-fold purification of galactosyltransferase activity with no detectable IgG by radioimmunoassay. Immunization of rabbits with this preparation produced antibodies directed against galactosyltransferase activity and minimal anti-Ig. The persistence of immunoglobulins during the purification of soluble galactosyltransferase activity through two enzyme-specific affinity chromatographic steps suggests an association of immunoglobulins with galactosyltransferase activity.

Thiocyanate interferes with iodination of protein by the chloramine-T method. A 50% reduction of 125 I incorporation into protein results from SCN − at 10 −5 m . A simple, rapid, and convenient method of detection of low levels of SCN − in protein solutions by its colored complex with Fe 3+ is described.

Serum IgA1 contains O-linked carbohydrate structures, whereas other immuno-globulins contain only N-linked structures. An assay was developed which detects IgA1 by measuring the DGalβ(1–3) DGalNAc structures O-linked to the IgA1 hinge region. Fifty percent of the serum specimens from cancer patients tested were elevated compared to 1% of the total normal serum specimens tested by this assay. The assay combines antibody (anti-human IgA) and lectin and measures the DGalβ(1–3)DGalNAc structure in the IgA1 molecule accessible to lectin binding. Three lectins were compared–the lectins from Bauhinia purpurea alba, Maclura pomifera, and peanut agglutinin (PNA). PNA in the assay discriminated best between serum specimens from normal subjects and cancer patients and was chosen as the lectin component in the assay. The anti-IgA-PNA enzyme immunoassay was evaluated in a retrospective study of cancer patients. A panel of 845 serum specimens was tested and the results analyzed at three cutoff R values. The R value of a specimen is the ratio of the assay absorbance obtained for that test specimen with respect to the assay absorbance obtained for a pool of normal human sera. At a cutoff R value of 2.38, 1% normals and 26% benigns were elevated. The following cancer specimens had elevated R values: 52% lung, 60% colon, 43% head and neck, 35% breast, 64% kidney, 38% bladder, 43% prostate, 8% ovarian, and 67% pancreas. Further testing showed a significant percentage of serum specimens from patients with cirrhosis, pancreatitis, or ulcerative colitis also had elevated R values. No correlation of this assay was observed with CEA levels. The results suggest that the carbohydrate structure of serum IgA1 is altered by malignancies and that measurement of this altered IgA may supplement CEA testing.

Summary The formation of antibody to human serum albumin (HSA) in rats was greatly enhanced when the protein was linked covalently to E. coli lipopolysaccharide (LPS). The response was less when HSA and LPS were only mixed before injection and nil when they were injected at separate sites subcutaneously. In rats the adjuvant effect of coupling LPS to HSA was comparable to that of using Freund's adjuvant or alum precipitation. In rabbits Freund's adjuvant was significantly the more effective. By the use of two qualitatively different detoxified derivatives, an adjuvant effect approximately equal to that of LPS was obtained with 1000-fold less pyrogenicity. The data suggest that LPS enhances antibody formation by acting directly upon the cells which respond to antigen, and possibly at the antigen-sensitive sites. In this effect both the lipid and polysaceharide portions of LPS appear to play a role, with lipid being the more important.

Our program on the mass cultivation of basidiomycetes was designed to determine whether these organisms, being more highly differentiated than bacteria, molds, and yeasts, would in turn carry out markedly different reactions on natural products. A discussion of our methods of isolating and characterizing a representative collection of basidiomycetes and of our difficulties in obtaining pure cultures which grew well is presented. Some information we obtained on the growth and types of products that these organisms produced in a synthetic medium is discussed. Our techniques for examining fermentation beers for transformation products from indole compounds and from progesterone are explained, and the types of products we obtained are described.

SummaryThe diphtheria bacilli growth test for β-alanine has been applied to a number of proteins and animal tissues. Skeletal muscle and liver were shown to be the richest animal sources of β-alanine, and β-alanine was shown to be absent from a number of purified proteins.