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PubMed2000

Ureide degradation pathways in intact soybean leaves.

Ureides dramatically accumulate in shoots of N(2)-fixing soybean (Glycine max L. Merr.) under water deficit and this accumulation is higher in cultivars that have N(2) fixation that is sensitive to water deficit. One possible explanation is that ureide accumulation is associated with a feedback inhibition of nitrogenase activity. A critical factor involved in ureide accumulation is likely to be the rate of ureide degradation in the leaves. There exists, however, a controversy concerning the pathway of allantoic acid degradation in soybean. Allantoate amidinohydrolase was reported to be the pathway of degradation in studies using the cultivar Maple Arrow and allantoate amidohydrolase was the pathway that existed in the cultivar Williams. This investigation was undertaken to resolve the existence of these two pathways. An in situ technique was developed to examine the response of ureide degradation in leaf tissue to various treatments. In addition, the response of ureide accumulation and N(2) fixation activity was measured for intact plants in response to treatments that differentially influenced the two degradation pathways. The results from these studies confirmed that Maple Arrow and Williams degraded allantoic acid by different pathways as originally reported. The existence of two degradation pathways within the soybean germplasm opens the possibility of modifying ureide degradation to minimize the influence of soil water deficits on N(2) fixation activity.

Allantoin↗

PubMed2000

Cannabinoid properties of methylfluorophosphonate analogs.

Methylarachidonylfluorophosphonate (MAFP) and related analogs have been shown to inhibit fatty acid amidohydrolase activity (FAAH), the enzyme responsible for hydrolysis of the endogenous cannabinoid ligand anandamide. To fully characterize this class of compounds, methylfluorophosphonate compounds with saturated alkyl chains ranging from C8 to C20 along with C20 unsaturated derivatives were synthesized and evaluated for their ability to interact with the CB1 receptor, inhibit FAAH, and produce in vivo pharmacological effects. These analogs demonstrated widely varying affinities for the CB1 receptor. Of the saturated compounds, C8:0 was incapable of displacing [(3)H]CP 55,940 binding, whereas C12:0 exhibited high affinity (2.5 nM). The C20:0 saturated analog had low affinity (900 nM), but the introduction of unsaturation into the C20 analogs restored receptor affinity. However, none of the analogs were capable of fully displacing [(3)H]CP 55,940 binding. On the other hand, all compounds were able to completely inhibit FAAH enzyme activity, with the C20:0 analog being the least potent. The most potent FAAH inhibitor was the short-chained saturated C12:0, whereas the other analogs were 15- to 30-fold less potent. In vivo, the C8:0 and C12:0 analogs were highly potent and fully efficacious in producing tetrahydrocannabinol (THC)-like effects, whereas the other analogs were either inactive or acted as partial agonists. None was capable of attenuating the agonist effects of THC. Conversely, the C20:0 analog potentiated the effects of anandamide but not those of 2-arachidonoyl-glycerol and THC. The high in vivo potency of the novel short-chain saturated MAFP derivatives (C8:0 and C12:0) underscores the complexity of manipulating the endogenous cannabinoid system.

Analgesics, Opioid↗

PubMed1975

Crystallographic studies on L-asparaginase from Proteus vulgaris. II. Symmetry and location of the tetrameric molecule.

Analyses of the x-ray diffraction intensity data by the Patterson synthesis and rotation function techniques show that the true space group of the monoclinic crystals of L-asparaginase (L-asparagine amidohydrolase, EC 3.5.1.1) from Proteus vulgaris is P21, that the molecular centers lie at x = 0.054, y = 0, z = 0.256, and its symmetry related positions, and that the tetramer molecules possess three approximate, mutually perpendicular 2-fold rotational symmetries, the axes of which run along the directions of the crystallographic a*-, b-, and c-axes. In addition, an investigation of the molecular packing arrangement in the crystal indicates that the tetramer molecules possess an approximately regular tetrahedral subunit structure.

Asparaginase↗

PubMed1975

[Renal glutaminase I activities in experimental and human chronic pyelonephritis (author's transl)].

QUESTION: For more exact knowledge on the pathogenesis of pyelonephritis a series of large scale histochemical and biochemical investigations were performed. In this study the author reports his observations on the renal glutaminase I activities in experimental and human pyelonephritis. MATERIALS AND METHODS: Details on materials and methods were given in a recent paper [PHILIPPSON, Exp. Path. 8, 182-193 (1973)]. Glutaminase I activities (L-glutamine amidohydrolase, EC 3.5.1.2.) were quantitatively analyzed according to MATTENHEIMER and DEBRUIN (7) in which the reaction was not only produced by cooling but also by simultaneous inhibition by means of 15% trichloric acetic acid. Ammonia was released and determined by Berthelot's reaction as modified by WELLER (18). RESULTS: The results in rabbit kidneys are compiled in the tables 1-3, the observations on human kidneys are represented in table 4. 139 rabbits showed unilateral experimental pyelonephritis, in 19 rabbits pyelonephritis did not develop or "healed up spontaneously". 31 samples of pyelonephritic nephrocirrhotic human kidneys (obtained by surgical operations) and 20 samples of healthy human kidneys were investigated. After separation of renal cortex and medulla the cortex was separated into glomerula and renal tubules by differential centrifugation. Significance was tested by universal comparison of the group mean values by t-test (rabbit and human kidneys separately). 1. In the rabbit glomerula glutaminase I (glut I) activities were increased significantly from the beginning of the experiment up to 100 days. They decreased markedly in the subsequent nephrocirrhotic stage (fig. 1). 2. The glut I activities in the rabbit cortical tubules decreased immediately, intensively and succesively up to the late-chronic nephrocirrhotic stage. 3. The rabbit medullary glut I showed likewise intensive decrease in the acute and subacute phase progressing to very low activities in the nephrocirrhotic stages. 4. In all samples from human pyelonephritic nephrocirrhoses (glomerula, cortical tubules and medulla) extremely decreased glut I activities were demonstrated. 5. The enzyme activities observed and the results of the semiquantitative histological analysis [SORGER and co-workers, Exp. Path. 9, 280-287 (1974)] are closely correlated. 6. In the glomerula of the "spontaneously healed up" tissue the glut I activities were markedly increased whereas they were moderately decreased in the cortical tubules and in the medulla. 7. The dry weights and values of protein content were equal to those earlier reported (PHILIPPSON 1973). 8. In the significance test (universally applied t-test) the overwhelming majority of the values showed high significance (p less than or equal to 0.001). The results are correlated with the observations of the semiquantitative histological analysis (SORGER et al. 1974) and discussed on the basis of data reported in literature.

Animals↗

PubMed1992

[Serum creatinine assay: results of a multicentric study with 16 analytical systems].

During a multicenter evaluation, 16 methods for creatinine measurement have been tested according to the guidelines of the Société française de biologie clinique (SFBC) protocol. Kinetic Jaffé methods, widely used in France, performed on different analytical systems (Astra Beckman, IL 508, RA 1000 Technicon, Hitachi 704, 705, 717 Boehringer, Fara Roche, Progress Kone, Kem-O-Mat Coulter, Perspective France Monitor) have been compared to a continuous flow method with aqueous standards, to enzymatic methods using creatinine amidohydrolase with a colorimetric measurement (Boehringer and Ektachem Kodak) and to an HPLC method. Reproducibility, estimated with four different control sera, proved to be unsatisfactory in some cases as compared to current criteria for imprecision (less than +/- 10 mumol/l for intralaboratory and less than +/- 20 mumol/l for interlaboratory imprecision). The same selected patients sera covering the whole range of physiopathological concentrations have been analyzed with each method, and compared with the continuous flow results. Differences are more dependent on the sample than on the calibrators. The influences of haemolysis, bilirubin, acetoacetate, albumin, lipids, glucose, and some cephalosporins have been evaluated with spiked human sera. Haemolysed, turbid and jaundiced patient samples have been analyzed as well. The results vary according to the analytical procedure. This study took place in the implementation of a selected method for routine purpose with special regards to interferences and an acceptable imprecision. The method must satisfy the physicians' demands in the renal function exploration, especially in kidney-transplant patients.

Biological Assay↗

PubMed1992

Automated microanalysis of creatinine by coupled enzyme reactions.

Hydrogen peroxide was generated from creatinine by the sequential enzyme reactions of creatinine amidohydrolase, creatine amidinohydrolase and sarcosine oxidase. Hydrogen peroxide was, in turn, used stoichiometrically for the condensation of 4-aminoantipyrine and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine catalyzed by horse-radish peroxidase, resulting in the formation of quinone dye with maximum absorbance at 546 nm. The optimized assay conditions for the enzymatic determination of creatinine in a HITACHI 7250 autoanalyzer was established. This system, which requires less than 5 microliters of sample, was found to be the most economical for laboratories equipped with autoanalyzers.

Autoanalysis↗

PubMed2006

[The mechanism of action of cannabis and cannabinoids].

The effect ofcannabis can be explained on the basis of the function of the cannabinoid receptor system, which consists of CB receptors (CB1, CB2), endoligands to activate these receptors and an enzyme--fatty acid amidohydrolase--to metabolize the endoligands. The endoligands of the cannabinoid receptor system are arachidonic acid-like substances, and are called endocannabinoids. Indications exist that the body also contains arachidonic acid-like substances that inhibit fatty acid amido hydrolase. Various cannabinoids have diverse effects on the receptors, functioning as agonists, antagonists or partial antagonists, as well as affecting the vanilloid receptor. Many known effects ofcannabis can be explained on the basis of this mechanism of action as can the use ofcannabis in various conditions including multiple sclerosis, Parkinson's disease, glaucoma, nausea, vomiting and rheumatoid arthritis.

Cannabinoid Receptor Modulators↗

PubMed1991

Helicobacter pylori urease: properties and role in pathogenesis.

Urease (urea amidohydrolase, EC 3.5.1.5) catalyzes the hydrolysis of urea to yield ammonia and carbon dioxide. Research on this enzyme has gained momentum since the discovery of Helicobacter pylori as a causative agent of human gastritis. The remarkably high urease activity of each organism has served as the basis of diagnostic tests for the presence of the organism in the urease biopsy test and urea breath test. Urease undoubtedly plays a central role in H. pylori pathogenesis. Hydrolysis of urea with generation of ammonia may enable survival of this acid-sensitive organism in the gastric mucosa. Ammonia generated by urea hydrolysis may also produce severe cytotoxic effects within gastric epithelium. The enzyme also elicits a strong immune response during acute infection, suggesting that this abundant antigen is readily available to the immune system. An increase in serum IgG titer is predictive of ongoing infection. Much progress has been made with regard to the molecular biology of urease. The high molecular weight protein (estimated by several investigators to be 300-520 kDa) has been purified, revealing two distinct subunits of 29.5 kDa and 66 kDa, a unique subunit structure as compared with other microbial ureases. However, amino acid sequences are nevertheless well conserved when compared with other bacterial ureases and that of the jack bean, Canavalia ensiformis. Furthermore, genes encoding urease of H. pylori have been cloned, sequenced, and amplified by the polymerase chain reaction.

Animals↗

PubMed1991

Predictive, error-compensating kinetic method for enzymatic quantification of creatinine in serum.

Here we describe an error-compensating kinetic-based method for the enzymatic quantification of creatinine in serum. The method, which has a large linear range and very low dependency on experimental variables that influence enzyme activity, is based on the use of creatinine amidohydrolase in a four-step coupled reaction sequence to generate a product that is monitored photometrically. We collected data for absorbance vs time during two to four half-lives of each reaction and fit a first-order model to the data to compute the total absorbance change that would be measured if the reaction were monitored to completion. Computed values of absorbance change agreed well with measured values and varied linearly with creatinine concentration in the sample throughout the range examined: 44 to 1326 mumol/L. A twofold change in enzyme activity in the final reaction mixture (3.3 to 6.6 kU/L) produced changes of only 12% and 4% for creatinine concentrations of 44 and 353 mumol/L, respectively. Results (y) for 39 serum samples that contained creatinine concentrations between 20 and 1800 mumol/L agreed well with liquid-chromatographic results (x), yielding linear least-squares statistics of y = (1.03 +/- 0.01) x + (5 +/- 5) mumol/L (r = 0.995, Sy.x = 37 mumol/L). We conclude that the predictive kinetic approach is a robust method for the quantification of creatinine in serum.

Chromatography, High Pressure Liquid↗

PubMed1991

[Evaluation of urinary polyamines in patients with nasopharyngeal carcinoma].

A new and simple enzymatic assay utilizing an acylpolyamine amidohydrolase and putrescine oxidase was adopted for measuring urinary polyamines (U-Pa). Serum carcinoembryonic antigen (S-CEA) was determined for comparison. The study population consisted of patients with pathologically proven nasopharyngeal carcinoma (NPC) who were referred to Kaohsiung Medical College Hospital. We found that polyamine levels were markedly elevated during radiotherapy but declined when the treatment was completed. Thus mean polyamines and the positive rate of polyamine elevation was higher in patients suffering from an active stage of the disease than in patients whose cancer had stabilized. However, the level of carcinoembryonic antigen was not elevated whilst undergoing radiotherapy. Therefore, routine measurement of polyamine levels may have a clinical utility in monitoring the disease state of the tumor. However, the low sensitivity of U-Pa test (22%) precludes its use as an effective screening method for this condition. Nevertheless, because of its simplicity, convenience and rapidity for monitoring NPC, U-Pa test should be considered a valuable tool in the clinical investigation of NPC patients.

Carcinoembryonic Antigen↗

PubMed1990

Determination of creatinine in serum and urine by a rapid liquid-chromatographic method.

We describe an HPLC ion-pair procedure for rapid and specific evaluation of creatinine in serum and urine. We used a 15 cm X 4.6 mm ODS column with a 50/50 (by vol) mixture of sodium decanesulfonic acid (10 mmol/L, pH 3.2) and methanol and measured absorbance at 236 nm. Serum (100 microL) or 30-fold-diluted urine (100 microL) was added to 400 microL of acetone. After centrifugation, the supernates (300 microL) were dried, reconstituted with the mobile phase, and injected into the HPLC. Assay precision was tested for concentrations of 10, 29, and 130 mg/L and yielded, respectively, 3.1%, 2.1%, and 1.1% for within-day CV and 2.8%, 2.1%, and 2.2% for total CV. Analytical recovery was 102 (+/- 6.7%). Linearity was demonstrated in the 0-200 mg/L range for serum and 0-3.5 g/L range for urine (r greater than or equal to 0.999). The detection limit for creatinine (signal-to-noise ratio = 3) was 0.5 mg/L. We used cimetidine for internal standardization. Correlation was good between this procedure and the Jaffé kinetic, the enzymatic (creatinine amidohydrolase), and the Fuller's earth alkaline picrate methods.

Chromatography, High Pressure Liquid↗

PubMed1989

Presence of two endo-beta-N-acetylglucosaminidases in human kidney.

We have isolated for the first time two kinds of endo-beta-N-acetylglucosaminidases (E-beta-GNases) simultaneously from human kidney. E-beta-GNase 1 was purified by water extraction, ammonium sulfate fractionation, and chromatography on Sephadex-G-200, DEAE-Sephadex, concanavalin A-Sepharose and Hypatite C columns. After the DEAE-Sephadex step, 107 units of E-beta-GNase 1 with a specific activity of 0.53 units/mg was obtained and after hydroxyapatite column, the enzyme recovery was 26 units with a specific activity of 10.4 units/mg. This enzyme hydrolyzed the high mannose-type asparaginylglycopeptide efficiently and had little activity toward the complex-type glycopeptide. This enzyme had an pH optimum at about 4.5 and was not inhibited by acetate ion. The Asn residue in a glycopeptide appeared not to be an important recognition site for E-beta-GNase 1 to express its activity because the acetylation or the dansylation of Asn residues as well as the elimination of Asn residue from the glycopeptide did not change the susceptibility of the oligosaccharide to E-beta-GNase 1. E-beta-GNase 2 was purified by water extraction, ammonium sulfate fractionation, and chromatography on Sephadex G-200, DEAE-Sephadex, concanavalin A-Sepharose, and Mono S columns. This enzyme was purified about 110-fold with 6.6% recovery. E-beta-GNase 2 was found to be a novel type of E-beta-GNase that hydrolyzed both the high mannose-type and the complex-type oligosaccharide with chitobiosyl group at the reducing end and without the Asn. E-beta-GNase 2 activity was found to be dependent on a L-aspartamido-beta-D-N-acetylglucosamine amidohydrolase (Asn-GNase) for the hydrolysis of asparaginylglycopeptide. Asn-GNase cleaved off the Asn residue from the glycopeptide, and the resulting oligosaccharide was hydrolyzed by E-beta-GNase 2. Because the acetylation or the dansylation of Asn residue in a glycopeptide rendered the glycopeptide resistant to Asn-GNase, the use of the modified asparaginylglycopeptide could not reveal the existence of E-beta-GNase 2 activity. The pH optimum of E-beta-GNase was found to be about 3.5. Like beta-hexosaminidases, this enzyme was inhibited by acetate ion, suggesting the recognition of GlcNAc moiety by this enzyme.

Acetylglucosaminidase↗

PubMed1978

Polymorphism of the cobalt-activated acylase in human tissues.

A method was elaborated for obtaining polyacrylamide gel zymograms of the cobalt-activated acylase after electrophoresis. Two fractions of the acylase showing activity towards N-chloroacetyl-gamma-L-glutamyl-beta-naphthylamide were found in human kidney, liver and intestine. The two fractions isolated from liver differ in substrate specificity, heat resistance, response to metal ions, inhibition by deaminated dipeptides, and in molecular weight. They differ also from other N-acylamino acid amidohydrolases: aminoacylase (EC 3.5.1.14) and aspartoacylase (EC 3.5.1.15).

Aminopeptidases↗

PubMed1988

Nickel as a micronutrient element for plants.

The detrimental effects of excessive Ni on plant growth have been well known for many years. More recent evidence indicates that Ni is required in small amounts for normal plant growth and development. Ni is an essential component of urease in plants and microorganisms. A deficiency of Ni in plants is reported to result in necrotic lesions in leaves in response to toxic accumulations of urea. Urease plays an essential role in mobilization of nitrogenous compounds in plants, a process that is especially important during seed germination and fruit formation when protein reserves are degraded into amino acids. Arginine, an abundant amino acid in plants, when degraded produces urea as a product and urease is needed for urea utilization. Theories of urea formation during allantoin degradation in Glycine max have been recently refuted. In G. max ureides apparently are metabolized via an amidohydrolase reaction with subsequent degradation of ureidoglycine, yielding glyoxylate, NH+4 and CO2. No evidence is available for the formation of urea in this pathway. Nitrogen-fixing symbionts, such as Rhizobium and Bradyrhizobium, contain two known Ni enzymes: urease and hydrogenase. Optimum growth of nodulated legumes and actinorhizal plants may depend on an adequate supply of Ni to meet the requirements of the Ni-requiring enzymes in host plants and endophytes. The seeds of severely Ni-deficient Hordeum are completely inviable, thus providing conclusive evidence for the essentiality of Ni for this species. The evidence indicates that Ni must be added to the list of micronutrient elements generally required by plants.

Nickel↗

PubMed1977

Dependence of mitochondrial protein synthesis initiation on formylation of the initiator methionyl-tRNAf.

The effect of N10-formyl-H4folate on mitochondrial peptide chain initiation has been studied in isolated mitochondria of Saccharomyces cerevisiae. The addition of N10-formyl-H4-folate strongly stimulates the incorporation of amino acids into mitochondrial protein at both 6 and 15 mm Mg2+. Still higher stimulation (up to 10-fold) has been obtained in the production of de novo synthesized initial peptides, measured as peptidyl puromycin derivatives. The maximum effect is observed at 0.1 mM N10-formyl-H4folate. At 5 mM puromycin, the ratio formylated/unformylated peptides is 3, as shown by electrophoretic analysis. At 10 mM puromycin, the ratio is increased to more than 6. This is due to the presence of deformylase and amidohydrolase activities, which are more effective the longer the initial peptide is synthesized; at increasing puromycin concentrations, progressively shorter peptide chains are formed. Chemically synthesized fMet-puromycin and Met-puromycin are virtually stable when incubated with intact or frozen and thawed mitochondria. More careful kinetic analysis shows an early cessation of the initial peptide formation in the samples without N10-formyl-H4-folate. This indicates that the formylation of methionyl-tRNA formylatable species is an absolute requirement for mitochondrial peptide chain initiation.

Drug Stability↗

PubMed1985

Higher homolog and N-ethyl analog of creatine as synthetic phosphagen precursors in brain, heart, and muscle, repressors of liver amidinotransferase, and substrates for creatine catabolic enzymes.

Tissues of chicks fed 5% N-methyl-3-guanidinopropionate (N-amidino-N-methyl-beta-alanine) for 12 days accumulated the following amounts of free plus phosphorylated derivatives as mumol/g, wet weight: brain, 5.5; heart, 7.3; leg muscle, 21.0; and breast muscle, 24.4. Since total creatine levels remained nearly the same in brain, N-methyl-3-guanidinopropionate-P provided brain with a supplemental reservoir of high energy phosphate. Tissues of rats fed 2% N-ethylguanidinoacetate (N-amidino-N-ethylglycine) accumulated large amounts of N-ethylguanidinoacetate-P, which has thermodynamic properties similar to creatine-P and is the kinetically most reactive synthetic phosphagen yet described. N-Ethylguanidinoacetate derivatives replaced creatine derivatives mole-for-mole, and the fraction of synthetic to total phosphagen after 19 days was 60% in heart, 54% in slow oxidative muscle, 42% in fast glycolytic muscles, and 22% in brain. N-Ethylguanidinoacetate served as a false end product co-repressor of liver arginine:glycine amidinotransferase levels in both chicks and chick embryos; N-methyl-3-guanidinopropionate and N-propylguanidinoacetate were relatively inactive. Creatinine amidohydrolase reversibly cyclized both N-ethylguanidinoacetate and N-propylguanidinoacetate with even lower Km values than for creatine derivatives, but it did not react significantly with N-methyl-3-guanidinopropionate, 3-guanidinopropionate, or 1-carboxy-methyl-2-imino-imidazolidine (cyclocreatine). Creatine amidinohydrolase also hydrolyzed N-acetimidoylsarcosine, but was relatively unreactive toward N-ethylguanidinoacetate, N-methyl-3-guanidinopropionate, 3-guanidinopropionate, and cyclocreatine. Amidinohydrolase can therefore be used to remove interfering creatine in assays of tissues for coexisting N-ethylguanidinoacetate or N-methyl-3-guanidinopropionate. Assays are now available to follow changes during metabolic stresses of any combination or all of the following phosphagens accumulated by the same tissue: creatine-P, N-ethylguanidinoacetate-P, cyclocreatine-P, N-methyl-3-guanidinopropionate-P, and homocyclocreatine-P.

Amidinotransferases↗

PubMed1983

Enzymic creatinine assay: a new colorimetric method based on hydrogen peroxide measurement.

We describe a new colorimetric method for measuring creatinine in serum and urine. Creatinine hydrolysis is catalyzed by creatinine amidohydrolase, and the creatine so produced is assayed in reactions catalyzed sequentially by creatine amidinohydrolase and sarcosine oxidase in a system that generates hydrogen peroxide. The hydrogen peroxide is measured at 510 nm in a reaction catalyzed by horseradish peroxidase, with 3,5-dichloro-2-hydroxybenzenesulfonic acid/4-aminophenazone as the chromogen. This series of reactions is complete in 30 min at room temperature. A blank sample measurement corrects for endogenous creatine. The standard curve is linear for creatinine concentrations as great as 2.21 mmol/L. Analytical recovery of creatinine in human sera and urine averaged 99.8%. Within-run and between-run precision studies gave CVs of less than or equal to 3.3 and less than or equal to 4.3% for a serum with a creatinine concentration of 69 mumol/L. Results by this method agree well (r greater than 0.99) with those by both the enzymic ultraviolet method of Wahlefeld and the fuller's earth/Jaffé method.

Benzenesulfonates↗

PubMed1976

Evidence for the association of L-asparaginase with cytomembrane components in the guinea pig liver soluble fraction.

Homogenization of guinea pig liver in isotonic sucrose solution followed by the separation of the subcellular fractions by differential centrifugation releases the liver L-asparaginase (L-asparagine amidohydrolase, EC 3.5.1.1) activity into the supernatant fraction. Electron micrographs of the liver L-asparaginase-antibody complexes, precipitated from the clear supernatant phase by addition of L-asparaginase-specific antiserum, show membrane-liek structures and some amorphous material. The attachment of L-asparaginase to the membrane-like structures is indicated by the ferritin-labeled antibody technique. The immunoprecipitates possess low activities of 5'-nucleotidase, alkaline phosphodiesterase I, NADPH cytochrome c reductase, glucose-6-phosphatase, and acid phosphatase. This observation suggests that L-asparaginase found in the liver supernatant fraction is associated with cytomembrane components. Analysis of guinae pig serum L-asparaginase-antibody complexes is polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate gives three distinct protein bands. These bands correspond to heavy and light chains of rabbit immunoglobulins and the L-asparaginase subunits. Analysis of the liver L-asparaginase-antibody complexes by the above procedure shows similar but more diffuse protein bands.

Animals↗