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Biomedical subjects

L Ma

Publications and source records attributed to L Ma.

At least 415 records · Page 23Linked to original sources
PubMed1996

Functional and structural alterations with 24-hour myocardial hibernation and recovery after reperfusion. A pig model of myocardial hibernation.

BACKGROUND: Short-term myocardial hibernation of 3 hours resulting from a moderate resting coronary flow reduction has been reproduced in pigs. This study was designed to determine whether any structural changes accompany short-term hibernation caused by a moderate flow reduction maintained for 24 hours and whether any such structural alterations are reversible after reperfusion. METHODS AND RESULTS: A severe left anterior descending coronary artery (LAD) stenosis was created with a reduction of resting flow to approximately 60% of baseline and maintained for 24 hours. Regional coronary flow was measured by a flowmeter; wall thickening was determined by echocardiography, and local metabolic changes were measured. Of 17 pigs, 11 completed the study protocol of 24 hours. The LAD flow was reduced from 0.91 +/- 0.11 to 0.52 +/- 0.13 mL.min-1.g-1, a 43% mean decrease, at 15 minutes after the LAD stenosis and was maintained at 0.56 +/- 0.11 mL.min-1.g-1 at 24 hours. The reduction of regional coronary flow initially produced acute myocardial ischemia, as evidenced by reduced regional wall thickening (from 37.2 +/- 6.9% at baseline to 11.5 +/- 6.8%), regional lactate production (-0.34 +/- 0.28 mumol.g-1.min-1), and a decrease in regional coronary venous pH (from 7.41 +/- 0.035 at baseline to 7.30 +/- 0.030). At 24 hours, the reductions in coronary flow and wall thickening were maintained relatively constant and the rate-pressure product was relatively unchanged, but lactate production ceased and regional H+ concentration normalized, with a tendency toward a further reduction in regional oxygen consumption, from 3.10 +/- 0.90 mL.min-1.100 g-1 at 15 minutes after stenosis to 2.52 +/- 0.95 mL.min-1.100 g-1 at 24 hours (P = .06), indicating metabolic adaptation of the hypoperfused regions. Of 11 pigs, 6 were free of myocardial infarction; 3 had patchy necrosis involving 4%, 5%, and 6% of the area at risk; and 2 other pigs had a few scattered myocytes with necrosis, detected only by light and electron microscopy. Ultrastructural changes consisted of a partial loss of myofibrils and an increase in mitochondria and glycogen deposition. Regional wall thickening recovered 1 week after reperfusion in most pigs, and the ultrastructural changes reverted to normal. CONCLUSIONS: In this pig model, moderately ischemic myocardium undergoes metabolic and structural adaptations but preserves the capacity to recover both functionally and ultrastructurally after reperfusion.

Actin Cytoskeleton↗
PubMed1996

SKP1 connects cell cycle regulators to the ubiquitin proteolysis machinery through a novel motif, the F-box.

We have identified the yeast and human homologs of the SKP1 gene as a suppressor of cdc4 mutants and as a cyclin F-binding protein. Skp1p indirectly binds cyclin A/Cdk2 through Skp2p, and directly binds Skp2p, cyclin F, and Cdc4p through a novel structural motif called the F-box. SKP1 is required for ubiquitin-mediated proteolysis of Cin2p, Clb5p, and the Cdk inhibitor Sic1p, and provides a link between these molecules and the proteolysis machinery. A large number of proteins contain the F-box motif and are thereby implicated in the ubiquitin pathway. Different skp1 mutants arrest cells in either G1 or G2, suggesting a connection between regulation of proteolysis in different stages of the cycle.

Amino Acid Sequence↗
PubMed1996

Electron paramagnetic resonance imaging of rat heart with nitroxide and polynitroxyl-albumin.

Electron paramagnetic resonance (EPR) imaging utilizing stable nitroxyl radicals is a promising technique for measuring free radical distribution, metabolism, and tissue oxygenation in organs and tissues [Kuppusamy, P., Chzhan, M., Vij, K., Shteynbuk, M., Lefer, D. J., Giannella, E., & Zweier, J. L. (1994) Proc. Natl. Acad. Sci. U.S.A. 91, 3388-3392]. However, the technique has been limited by the rapid reduction of nitroxide in vivo to its hydroxylamine derivative, a diamagnetic, EPR-inactive species. In this report a novel, polynitroxylated derivative of human serum albumin is shown to be capable of reoxidizing the hydroxylamine back to nitroxide in vivo. Polynitroxyl-albumin (PNA) is shown to be effective in maintaining the signal intensity of the nitroxide 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL or TPL) in the ischemic isolated rat heart, allowing the acquisition of high-resolution three-dimensional (3D) EPR images of the heart throughout a prolonged 2.5 h period of global cardiac ischemia. In serial transverse sections of the 3D image, TPL intensity maps of the heart showed cardiac structure with submillimeter resolution. TPL intensities in coronary arteries and myocardium showed that nitroxide concentration decreases with increasing distance from large blood vessels. These results demonstrate that EPR imaging in vivo is possible using nitroxides in conjunction with PNA. In addition to its utility in the emerging technology of EPR imaging, the greatly prolonged half-life of TPL observed in the presence of PNA may facilitate the therapeutic application of nitroxides in a variety of disease processes.

Animals↗
PubMed1996

An experimental model for studying passive cigarette smoking effects on gastric ulceration.

Cigarette smoking is associated with gastric mucosal damage in humans. For this study, a smoke chamber was designed to investigate the effects of passive smoking on gastric ulceration. Different concentrations of cigarette smoke (0%, 1%, 2%, and 4%) were perfused into a chamber for one hr in which conscious rats were placed. This one-hr smoke exposure potentiated ethanol (70%, v/v, p.o.)-induced gastric mucosal damage and increased serum nicotine levels; however, it did not affect the blood pH, pCO2, pO2, and HCO3 concentrations, or the systemic blood pressure and heart rate. Under these experimental conditions, exposure to cigarette smoke produced no significant changes in the blood acid/base balance and stress in the animals but significantly potentiated ethanol-induced gastric mucosal damage. The present experimental model is suitable for studying the adverse interactions between passive smoking and alcohol drinking in gastric ulcer formation in rats.

Animals↗
PubMed1996

Construction of a form of the MoFe protein of nitrogenase that accepts electrons from the Fe protein but does not reduce substrate.

The direction of electron flow through nitrogenase is generally believed to be from the Fe protein to the P-clusters to the FeMo cofactor and then to substrate. In order to examine oxidation states of the P-clusters that might be involved in this pathway, we have constructed a form of the MoFe protein that contains a species called the MoFe cluster (Gavini, N., Ma, L., Watt, G., and Burgess, B.K. (1995) Biochemistry 33, 11842-11849) in place of FeMo cofactor. This MoFe cluster-containing protein was purified, and the presence of the cluster was confirmed by reisolation of the MoFe cluster followed by EPR spectroscopy. The protein does not reduce protons or acetylene, however, upon the addition of the Fe protein and MgATP, MgATP hydrolysis occurs at a rate 28% of the wild-type protein. As isolated in the presence of excess dithionite the MoFe cluster-containing protein is EPR silent. Upon addition of the Fe protein and MgATP a g = 1.94 EPR signal develops that integrates to about 1 spin per P-cluster. This signal only develops when both the Fe protein and MgATP are added and it arises from the P-clusters.

Azotobacter vinelandii↗
PubMed1996

Quantification of polycyclic aromatic hydrocarbons and polychlorinated dibenzo-p-dioxins in human serum by combined micelle-mediated extraction (cloud-point extraction) and HPLC.

Quantification of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated dibenzo-p-dioxins (PCDDs) usually requires preconcentration and cleanup prior to analysis. These procedures often involve using large amounts of toxic organic solvents. The sample preparation from serum is even more complex because of the coextraction of lipids and other nonpolar serum components. We describe the unprecedented use of cloud-point extraction to preconcentrate, extract, and clean up PAHs and PCDDs from human serum using the nonionic surfactant Triton X-100. The samples were analyzed by high-performance liquid chromatography with ultraviolet detection. The phase separation was induced by the addition of salt to the micellar serum solutions. The surfactant-rich phase was treated with acetonitrile and water to precipitate and remove some of the unwanted substances in the serum sample extract without significantly affecting the recoveries of the analytes. The favorable characteristics of cloud-point extraction discussed here strengthen its potential use as an alternative to other techniques of separation.

Chromatography, High Pressure Liquid↗
PubMed1996

Abnormal assembly of membrane proteins in erythroid progenitors of patients with beta-thalassemia major.

The life threatening anemia in beta-thalassemia major (Cooley's anemia) is characterized by profound intramedullary lysis, the cause of which is incompletely understood. Using marrow obtained from beta thalassemia major patients undergoing allogeneic bone marrow transplantation in Pesaro Italy, it became possible to directly study the mechanism of the intramedullary hemolysis. Based on our previous studies, we hypothesized that the unmatched alpha globin chains would interfere with normal assembly of erythroid precursor membrane proteins. Patient and control erythroid precursors were reacted with monospecific polyclonal rabbit antibodies directed against spectrin, band 3, and band 4.1 and with a monoclonal anti-alpha globin chain antibody. Using laser confocal fluorescence microscopy, normal erythroid precursors show no alpha globin chain accumulation and exhibited uniformly smooth rim fluorescence of the three membrane proteins. In some thalassemic precursors, spectrin appeared to interact with large alpha globin accumulations, and in many of these cells the spectin appeared clumped and discontinuous. Band 4.1 interacted strongly with accumulations of alpha globin in thalassemic precursors to produce bizarrely clumped zones of abnormal band 4.1 distribution. Band 3 was incorporated smoothly into thalassemic erythroblast membranes. However, the proerythroblasts and basophilic erythroblasts were significantly deficient in band 3. Thus, accumulations of alpha globin in beta-thalassemia major colocalized with and disrupt band 4.1 and spectrin assembly into the membrane. The cause of deficient band 3 incorporation into thalassemic proerythroblast membranes remains unknown. These profound membrane alterations would likely contribute to the intramedullary lysis seen in Cooley's anemia.

Animals↗
PubMed1996

Kinetic and X-ray structural studies of a mutant Escherichia coli alkaline phosphatase (His-412-->Gln) at one of the zinc binding sites.

Site-specific mutagenesis has been used to replace His-412 with glutamine in Escherichia coli alkaline phosphatase. In the wild-type enzyme His-412 is a direct ligand to one of the catalytically important zinc atoms (Zn1) in the active site. The mutant enzyme (H412Q) exhibited about the same k(cat), but a 50-fold increase in K(m) compared to the corresponding kinetic parameters for the wild-type enzyme. Furthermore, the H412Q enzyme had a lower zinc content than the wild-type enzyme. In contrast to the wild-type enzyme, Tris was less effective in the transferase reaction and dramatically inhibited the hydrolysis reaction of the H412Q enzyme. The addition of zinc to the mutant enzyme increased the k(cat) value above that of the wild-type enzyme, partially restored the weak substrate and phosphate binding, and also alleviated the inhibition by Tris. The structure of the H412Q enzyme was also determined by X-ray crystallography. The overall structure of the H412Q enzyme was very similar to that of the wild-type enzyme; the only alpha-carbon displacements over 1 angstrom were observed near the mutation site. In the H412Q structure no phosphate was bound in the active site of the enzyme; however, two water molecules were observed where phosphate normally binds in the wild-type enzyme. Close examination of the active site of the H412Q structure revealed structural changes in Ser-102 as well as at the mutation site. For example, the carbonyl oxygen of the side chain of Gln-412 rotated away from the position of His-412 in the wild-type structure, although too far away (3.2 angstroms) to coordinate to Zn1. Studies on the H412Q enzyme, and a comparison of the H412Q and H412N structures, suggest that the structure and electostatics of the imidazole ring of histidine are critical for its function as a zinc ligand in alkaline phosphatase.

Alkaline Phosphatase↗
PubMed1996

NMR determination of the structure of Julibroside J1.

Julibroside J1 is a new triterpenoid saponin which contains one triterpene, two monoterpenes and nine sugar residues. The structure has been determined almost exclusively by high-resolution NMR methods. The 1H and 13C NMR spectra of Julibroside J1 C5D5N have been assigned by homonuclear and heteronuclear correlation experiments, such as COSY, CH-COSY, TOCSY, HMBC, HMQC-COSY, HMQC-TOCSY and NOESY. Anomeric configurations were obtained by combined use of 1JCH and 3JH1,H2 and NOESY data. The particular sugar residues were identified by utilizing 3JHH values obtained from TOCSY cross-peaks, NOE difference spectra, and several 1D-TOCSY spectra, and three-bond intra-ring cross-peaks from a HMBC spectrum. Linkage assignments were made using the HMBC spectrum, and supplemented by NOE data from the NOESY spectrum. The structure of Julibroside J1 was characterized as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D- glucopyranosyl]-21-O-((6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-[4-O-((6 S)- 2-trans-2,6-dimethyl-6-O-(6-deoxy-beta-D-glucopyranosyl)-2,7-octadien oyl)-6- deoxy-beta-D-glucopyranosyl]-2,7-octadienoyl)-acacic acid 28-O-(beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4)]- alpha-L-rhamnopyranosyl-(1-->2))-beta-D-glucopyranosyl ester.

Carbohydrate Conformation↗
PubMed1996

Localization of myotonic dystrophy protein kinase in skeletal muscle and its alteration with disease.

Myotonic dystrophy (DM) is an autosomal dominant disorder which affects skeletal muscle, heart, eye lens, brain, and endocrine functions. The disease-causing mutations are expansions of the triplet repeat CTG in the 3' untranslated region of a locus which encodes a serine/threonine protein kinase that represents a new family of protein kinases. A monoclonal antibody to a recombinant DM protein kinase (mAb DM-1) reacts specifically with the 64 kDa isoform of DM protein kinase in type I fibers in skeletal muscle, the fiber type which characteristically atrophies in the disease. Within type I fibers of normal muscle the isoform may be localized with mAb DM-1 to the triad region. In the DM disease state, the enzyme is redistributed to the pathologically characteristic peripheral sarcoplasmic masses. In markedly affected human distal myotonic muscle, the levels of the 64 kDa DM kinase isoform are elevated relative to slow skeletal myosin heavy chain. These results suggest that, consistent with the dominant clinical phenotype, the localization and accumulation of the 64 kDa isoform are altered in the heterozygous disease state.

Acrylic Resins↗
PubMed1996

Expression of an Msx homeobox gene in ascidians: insights into the archetypal chordate expression pattern.

The Msx homeobox genes are expressed in complex patterns during vertebrate development in conjunction with inductive tissue interactions. As a means of understanding the archetypal role of Msx genes in chordates, we have isolated and characterized an Msx gene in ascidians, protochordates with a relatively simple body plan. The Mocu Msx-a and McMsx-a genes, isolated from the ascidians Molgula oculata and Molgula citrina, respectively, have homeodomains that place them in the msh-like subclass of Msx genes. Therefore, the Molgula Msx-a genes are most closely related to the msh genes previously identified in a number of invertebrates. Southern blot analysis suggests that there are one or two copies of the Msx-a gene in the Molgula genome. Northern blot and RNase protection analysis indicate that Msx-a transcripts are restricted to the developmental stages of the life cycle. In situ hybridization showed that Msx-a mRNA first appears just before gastrulation in the mesoderm (presumptive notochord and muscle) and ectoderm (neural plate) cells. Transcript levels decline in mesoderm cells after the completion of gastrulation, but are enhanced in the folding neural plate during neurulation. Later, Msx-a mRNA is also expressed in the posterior ectoderm and in a subset of the tail muscle cells. The ectoderm and mesoderm cells that express Msx-a are undergoing morphogenetic movements during gastrulation, neurulation, and tail formation. Msx-a expression ceases after these cells stop migrating. The ascidian M. citrina, in which adult tissues and organs begin to develop precociously in the larva, was used to study Msx-a expression during adult development. Msx-a transcripts are expressed in the heart primordium and the rudiments of the ampullae, epidermal protrusions with diverse functions in the juvenile. The heart and ampullae develop in regions where mesenchyme cells interact with endodermal or epidermal epithelia. A comparison of the expression patterns of the Molgula genes with those of their vertebrate congeners suggests that the archetypal roles of the Msx genes may be in morphogenetic movements during embryogenesis and in mesenchymal-epithelial interactions during organogenesis.

Amino Acid Sequence↗
PubMed1996

Characterization of digoxigenin derivatives of human coagulation factors VIIa and X by electrospray mass spectrometry and enzyme kinetics.

Digoxigenin ester (Dig) derivatives of coagulation factors VIIa and X facilitate staining studies to localize tissue factor activity in human atherosclerotic plaques. The larger the number of attached Dig units the easier it is to form highly visual stains. Electrospray ionization was used to characterize the Dig derivatives, as a function of excess derivatization reagent, to determine the optimal derivatives, i.e. the highest number of Dig units attached with the product still retaining enzymatic activity. The enzymatic activity of factor VIIa derivatized at 50-fold Dig excess (with 28, 34, 48 or 52 Dig units attached, masses to 79 kDa) remained the same as that of native factor VIIa. In contrast, the enzymatic activity of factor X derivatives diminished above 15-fold Dig excess (15 Dig units attached, mass 65.6 kDa). The distribution of derivatized lysine, histidine, arginine, tryptophan and tyrosine residues was estimated for several possible configurations.

Amino Acids↗
PubMed1996

Urinary homovanillic acid and vanillylmandelic acid in workers exposed to carbon disulfide.

Homovanillic acid (HVA) and vanillylmandelic acid (VMA), two end products of dopamine metabolism, were measured in 60 workers exposed to carbon disulfide (CS(2)) in a rayon factory and in 48 unexposed workers. The airborne CS(2) concentrations in eight major exposure zones of the plant were measured monthly over a period of 4 years, from 1990 to 1994. In addition, the exposure concentrations and exposure history of each worker were integrated to estimate the overall lifetime exposure. Industrial hygiene data showed that the geometric mean concentrations of CS(2) in the plant ranged from 2.68 to 20.19 ppm, and more than 15% of the studied population had been repeatedly exposed to CS(2) at concentrations exceeding the ACGIH recommended time-weighted average of 10 ppm. The results showed that there was a significantly lower level and a higher proportion of CS(2) workers with decreased HVA and VMA excretion. However, there were no statistical correlations between the two dopaminergic metabolites and the mean CS(2) concentration, and years of employment. In contrast, significant dose-effect relationships were observed between these two metabolites and the integrated cumulative exposure (ICE) variable. The correlation coefficients for ICE and HVA, and ICE and VMA were -0.35 (p < 0.01) and -0.20 (p <0.05), respectively. These data suggest that chronic exposure to CS(2) was associated with measurable reduction in catecholamine metabolite concentrations. This finding is compatible with the earlier observations in laboratory animals that CS(2) exposures interfere with neurochemical metabolism.

Adult↗
PubMed1996

Induction of mouse beta integrin expression following transfection with human alpha 4 chain.

We report here an analysis of the expression and function of the alpha chain of human VLA-4 in stable mouse L cell transfectants and the requirement for the beta chain in these processes. L cells were transfected with human alpha 4 cDNA or alpha 4 and human beta 1 cDNA. Unexpectedly, human alpha 4 cDNA, when transfected alone, could induce de novo surface expression of host beta 7 and increased expression of host beta 1. Induction of mouse beta 7 and beta 1 surface expression was not due to de novo gene activation, but instead represented alpha 4/beta intracellular subunit association and transport to the cell surface. Transfection with human beta 1 prevented surface expression of mouse beta integrins. Whereas human alpha 4 and human beta 1 subunits associated very tightly in anti-alpha 4 immunoprecipitates, human alpha 4 and mouse beta subunits were only partially associated. Furthermore, binding of human/mouse chimeric receptors to recombinant VCAM, a major ligand for alpha 4 beta 7 and alpha 4 beta 1, was very poor, whereas human alpha 4/human beta 1 receptors bound strongly to VCAM. One alpha 4 transfectant, which exhibited a tight human alpha 4/mouse beta 1 association, could be induced, but only after PMA activation, to bind strongly to VCAM. These results indicate that alpha 4 subunits have specific affinity for beta 7 and beta 1 integrins and require beta subunits for surface expression as well as high affinity ligand binding activity. Our results indicate that a tight association between the alpha 4 and beta subunit appears to be critical for ligand binding, consistent with a direct as well as regulatory role for the beta subunit in ligand binding. Furthermore, these studies demonstrate that expression of foreign recombinant proteins can alter host cell protein expression resulting in de novo surface protein expression.

Animals↗
PubMed1996

Ricin depresses cardiac function in the rabbit heart.

Ricin, at toxic glycoprotein from the castor bean, causes myocardial hemorrhage and a decrease in blood pressure. We studied the effects of ricin on myocardial function in the isolated rabbit heart. Rabbits were given 0.22 micrograms/kg of ricin i.v. and 48 hr later, the heart was isolated and retrogradely perfused through the aorta with Tyrode's solution. A latex balloon was inserted into the left ventricle and isovolumic left ventricular function curves were generated. Left ventricular developed pressure (LVDP), heart rate, coronary artery flow, left ventricular end diastolic pressure, myocardial oxygen consumption, oxygen extraction (a - vO2), and contractility (+dp/dt) were measured over a range of left ventricular volumes. Dose-response curves to isoproterenol (10(-9)-10(-8) M) and phenylephrine (10(-9)-10(-6) M) were also obtained. Compared to the control group, ricin pretreatment markedly decreased ventricular compliance (p < 0.01), diminished maximum left ventricular developed pressure (p < 0.05), and reduced maximal +dp/dt (p < 0.05). Myocardial oxygen consumption, heart rate, electrocardiographic PR, QRS, and QT intervals were not different in control and ricin treatment groups. Ricin did not significantly alter the inotropic or chronotropic responses to isoproterenol and phenylephrine. The results from the binding studies showed that ricin neither reduced beta-adrenergic receptor numbers nor altered the dissociation constant. thus, ricin reduced both systolic (LVDP and +dp/dt) and diastolic (compliance) left ventricular functions, perhaps due to increased vascular permeability, without altering responses to the alpha- and beta-adrenoceptor agonists phenylephrine and isoproterenol.

Adrenergic beta-Agonists↗
PubMed1996

Atrazine retention and transport in soils.

No pesticide has been studied as extensively as atrazine. The study of atrazine has contributed to our general understanding of the behavior of pesticides in soils. New knowledge and concepts were evaluated, such as atrazine adsorption kinetics, desorption hysteresis, and preferential flow. Corresponding conceptual models were also proposed to explain the behavior of atrazine in soils. Atrazine adsorption-desorption is the major process affecting atrazine behavior in soils and is mainly affected by organic matter and soil pH. Atrazine in soils is subject to biological and chemical degradations. Hydroxyatrazine, the chemical degradation product, is more strongly adsorbed to soil than atrazine. Deethylatrazine and deisopropylatrazine, the major biological degradation products, are more mobile than atrazine. Hydrolysis of atrazine is soil-surface catalyzed and favored by low soil pH. The overall dissipation rate of atrazine was found to be pseudo first-order. Two distinct and different processes are involved in atrazine movement: slow transport through the soil matrix and rapid movement through macropores. The first process is controlled by adsorption kinetics and degradation reactions and can be well explained by models based on chemical heterogeneity, such as the two-site models and second-order models. The second flow process results from preferential flow through large pores and can be explained by physical nonequilibrium models such as the mobile-immobile and two-flow domain models. Because both processes coexist in atrazine transport, coupling of physical and chemical nonequilibrium models is often necessary and has shown promise in atrazine transport modeling. However, more efforts are needed in estimating model parameters and in developing management-oriented models.

Adsorption↗
PubMed1996

Immobilization of prostaglandin synthetase by hydrophobic adsorption.

In this article, the immobilization of prostaglandin synthetase on n-alkyl or aryl amino-agar beads by hydrophobic adsorption is reported. The effects of different hydrophobic groups in the agar beads, pH of buffer, concentration of salts on the adsorption of prostaglandin synthetase, and the properties of immobilized prostaglandin synthetase were also studied. The results showed that 20-35 mg of microsome containing PG synthetase (protein content 8-15 mg) could be adsorbed on each gram of n-dodecylamino-agar beads after suction drying the gel in the buffer of pH 5.5 (containing 0.5 mol/L KCl), 0.1 mol/L citric-phosphate at 4 degrees C. The remaining immobilized enzyme activity was over 80%. The optimum pH of immobilized PG synthetase is 8.0, similar to that of the native enzymes. The thermostability of immobilized PG synthetase in the buffer containing 0.5 mol/L KCl was increased. Immobilized PG synthetase was used as a catalyst of synthesis of prostaglandin E1. The preservation of activity after 10 working cycles was 86.2%.

Adsorption↗