Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0267964 (PAA)
 2,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The substrate that was split most rapidly by acid phosphatase was p-nitrophenylphosphate. Two peaks of activity were obtained at pH 4.6-4.8 and 5.1-5.4. The enzyme remained stable for a long time when refrigerated. It was inhibited strongly by urea and tartrate, and slightly by fluoride and L-phenylalanine. Mercaptoethanol elicited pronounced activation of the enzyme. Four different forms of isoenzyme, giving rise to 11 phenotypes, were identified. A suitable analytical technique was electrophoresis on polyacrylamide gel with phosphate-citrate buffer. Mean activity was 3.15 +/- 0.41 units per gramme of haemoglobin haemolysate. Some of the isoenzyme preparations showed considerable variation in activity. There was no change in enzyme activity after temporary hypomagnesaemia. Acid phosphatase activity was high in testis, kidney and intestinal mucosa; myocardium, liver and spleen showed moderate activity. Five isoenzymes were demonstrable in a starch column and six in PAA gel.
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PMID:[Properties and isoenzymes of acid phosphatase in erythrocytes and various tissues (kidney, liver, spleen, small intestine mucosa, testis, myocardial and skeletal musculature) of cattle]. 122 26

Thirty-five Salmonella strains isolated from human cases of salmonellosis were tested and compared for their fibronectin (fn) binding capacities by using two fn-particle agglutination assays (fn-PAAs) prepared by coating with human fn either (i) latex beads (Difco; 0.81-micron diameter) (L-fn-PAA) or (ii) heat-killed formalin-treated Staphylococcus aureus Cowan 1 cells (C-fn-PAA). Six S. aureus strains were also included in this study as controls. The strains were cultured on colonization factor antigen agar and blood agar and in tryptic soy broth and brain heart infusion broth. The Salmonella and S. aureus strains were cultured at 33 and 37 degrees C, respectively, for optimal expression of fn-binding proteins. Bacterial cells (approximately 10(10) cells per ml) harvested from growth in various culture media and suspended in 0.02 M potassium phosphate buffer (pH 6.8) agglutinated the fn-PAA reagents. These reactions were scored semiquantitatively from + to + depending on the speed or intensity of the reactions within 2 min. Maximum agglutination in fn-PAA systems was observed when the cells were grown in brain heart infusion broth, while tryptic soy broth proved to be least suitable media for culturing cells for fn-PAAS. Although a statistically highly significant correlation was obtained between results of assays of radiolabeled fn and 29-kDa fragment binding, no significant correlation was observed (i) between the results of strains cultured in different media or (ii) when semiquantitative score results of the two fn-PAA systems were compared with those of the conventional radiolabeled fn assay. To enhance the efficiency of the test system, the C-fn-PAA reagent was stained with methylene blue (2% in 0.17 M glycine-NaOH buffer [pH 6.8]). This facilitated easy interpretation of results, which could be performed on hydrophobic paper instead of glass slides. The results obtained with both unstained C-fn-PAA and stained C-fn-PAA were comparable to each other and reproducible. Although the fn-PAAs are simple and easy to perform, the results did not differentiate between negative, low, moderate, and high binding abilities when Salmonella strains were evaluated for fn binding, and the results were not comparable to those obtained by the conventional radiolabeling method.
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PMID:Fibronectin binding by Salmonella strains: evaluation of a particle agglutination assay. 175 55

Fermentation parameters for the production of penicillin G acylase by Escherichia coli NCIM 2400 have been evaluated. The bacterium produced the enzyme intracellularly when grown in nutrient broth containing PAA. PAA stimulated the enzyme synthesis by 8-10 fold and reduced the lag period. The optimum concentration of PAA for induction was 20 mM and addition of PAA prior to inoculation gave maximum production of PGA. Glucose, lactose, sorbitol, acetate and lactate even at 0.1% concentration catabolically repressed the enzyme formation. Peptone was the best utilised 'N' source for the enzyme production. Phosphate and yeast extract were found to be essential for both the growth and for enzyme biosynthesis. Temperature between 22-24 degrees C was optimum and under ideal condition E. coli NCIM 2400 produced 0.45-0.55 U/ml of penicillin G acylase.
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PMID:Biosynthesis of benzylpenicillin acylase by Escherichia coli NCIM-2400. 269 12

The primary and secondary structure of herpes simplex virus type 1 (HSV-1), varicella-zoster (VZV) and Epstein-Barr virus (EBV) DNA polymerases was calculated by means of computer programs. The comparison of HSV-1 polymerase (pol) sequence to the known primary and tertiary structure of E. coli DNA pol I revealed five short homologous sequences, one of which coincided with the alpha-helical structure of the DNA-binding domain of E. coli DNA pol. Comparison by primary and secondary structure computer programs of the three DNA polymerases coded by herpesviruses HSV-1, VZV and EBV led to the identification of polypeptide sequences shared by the three DNA pols. In a similar way, the secondary structure of the DNA pol polypeptide in the vicinity of the mutation leading to PAA resistance in HSV-1 DNA pol helped to identify the role of this sequence in the binding of phosphate donated by the nucleoside triphosphate molecule which binds to the DNA pol. Although the computer secondary structure programs are about 60% accurate, it was possible to obtain new information on the properties of certain domains in the DNA polymerases of HSV-1, VZV and EBV.
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PMID:Computer-assisted primary and secondary structure analyses of DNA polymerases of herpes simplex, Epstein-Barr and varicella zoster viruses reveal conserved domains with some homology to DNA-binding domain in E. coli DNA pol I. 285 11

The 5'-PAA and 5'-PFA phosphate esters of 5-bromo-2'-deoxyuridine (BUdR) were synthesized and their antiherpes virus activity was evaluated in vitro. Both compounds showed activity of the same order as the parent nucleoside, BUdR, against HSV-2 but were 4 to 12 times less potent against HSV-1. The 5'-PAA phosphate ester of BUdR (Ro 21-9875) was also active against varicella-zoster virus (VZV) and human cytomegalovirus (HCMV). The 5'-PAA phosphate ester of 5-bromovinyl-2'-deoxyuridine (BVdU) was also synthesized and showed good antiviral activity against HSV-1 only (ID50 = 1.3 mg/l). Further evaluation against selected mutants (TK- or PAAr) indicated a requirement for the expression of the virus-coded thymidine kinase (TK) for the antiviral activity of Ro 21-9875. Kinetic studies revealed non-competitive mixed inhibition of the viral enzyme by this compound. This suggests that it may have some intrinsic TK mediated activity though breakdown to its component parts is undoubtedly a significant contributing factor.
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PMID:Antiviral activity of 5'-PAA and 5'-PFA phosphate esters of 2'-deoxyuridines. 294 89

The effect of N(6)-phenyl-N(6)-allyladenosine (PAA, BM 11.189) on myocardial ischemic stress was evaluated in six open-chest mongrel dogs during repeated coronary occlusions of 3 min. Whereas there was not significant change in hemodynamic parameters before and during coronary occlusions after treatment, PAA reduced significantly epicardial ST-segment elevations (-34%) during ischemia and myocardial release of lactate (-43%), phosphate (-44%), and potassium (-48%) in the early reperfusion period. PAA lowered significantly arterial non esterified fatty acids and converted oxidative myocardial metabolism from lipid to predominantly carbohydrate utilization, reflected by a shift of cardiac respiratory quotient from 0.81 to 1.01. The beneficial effects of PAA on myocardial ischemic injury could be explained by an improved economy of oxidative myocardial energy supply in the jeopardized border zone of the ischemic myocardium.
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PMID:Effects of a N(6)-disubstituted adenosine derivative on myocardial metabolism and ischemic stress following coronary occlusion. 343 85

The preparation of stroma-free hemoglobin by selective DEAE-cellulose absorption is reported. The stroma-free hemoglobin prepared by this method is compared to the product obtained by crystallization from sodium phosphate. Both show normal serum potassium, sodium, and pH values, and no coagulant activity or blood type activity by blood type test. PAA gradient gel electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and isoelectric focusing in polyacrylamide gel all show the same well-defined bands in both preparations. The DEAE procedure requires 11 h as compared to 4 days for the crystallization method. The recovery of hemoglobin is 77% (less than 1% methemoglobin) in the DEAE preparation compared to 34% (greater than 3% methemoglobin) by the crystallization method. In addition, far fewer expensive materials are required.
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PMID:The preparation of stroma-free hemoglobin by selective DEAE-cellulose absorption. 673 30

The interactions between acrylic-maleic acid (PAA-PMLA) copolymer with clay minerals are investigated in terms of adsorption/desorption behavior. The adsorption isotherms were obtained as a function of clay mineral structures, pH and ionic strength by sensitive polyelectrolyte titration and radiotracer methods. The nature and the location of binding sites for PAA-PMLA copolymer on aluminol sites at the edge surface can be stated. In the case of the adsorption on kaolinite, the pH-dependent interaction in relatively low ionic strength is discussed not only in terms of electrostatic contributions, but evidences for a ligand exchange mechanism are also presented. Increasing the ionic strength also enhances the adsorption by a screening of the charges in the adsorbed layer especially when the charges of the copolymer and the surface are of the same sign. The adsorbed PAA-PMLA copolymer can be displaced by phosphate compounds such as monophosphate and sodium tripolyphosphate (STP). The observed desorption process results from a competition between PAA-PMLA copolymer and phosphate compounds for the same binding sites on the kaolinite surface. Adsorption equilibrium constants can thus be derived from single and mixture adsorption isotherms. Effects due to the heterogeneity of the kaolinite surface and to the conformation of the adsorbed PAA-PMLA copolymer are also discussed. Strongly bound PAA-PMLA copolymer traces support the ligand exchange mechanism at the aluminol sites of the edge surface. Clay minerals may thus act as natural barriers in the soil transport of the polycarboxylates used in phosphate-free detergents.
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PMID:Adsorption-Desorption Behavior of Acrylic-Maleic Acid Copolymer at Clay Minerals 905 40

The axi-symmetric drop-shape analysis-pendant drop technique has been used to measure interfacial tension at the chlorobenzene-water interface in the presence of adsorbed films of dimyristoylphosphatidylcholine (DMPC), dipalmitoylphosphatidylcholine (DPPC), DMPC-cholesterol, DPPC-cholesterol, DMPC-cholesterol-dicetyl phosphate (DCP) and DPPC-cholesterol-DCP. A surface-pressure function, pi * = pi lipid-polymer -pi lipid (where pi lipid is the surface pressure of the mono-layer without polymer and pi lipid-polymer is the surface pressure of the lipid mono-layer and adsorbed polymer at equilibrium at the chlorobenzene-water interface) was used to characterize the interaction of eight water-soluble polymers with the lipid films. The equation, delta pi * = pi II*-pi I* (where the subscripts II and I denote the higher and lower lipid composites, respectively) was used to determine the differential effect of cholesterol and DCP on mono-layer characteristics in the presence of 1% w/v polymer. Cholesterol or polymer individually condensed DMPC films and expanded DPPC films. However, composite films of DMPC-cholesterol-DCP and carboxymethylchitin (CM-chitin), poly(acrylic acid) (PAA) or poly(vinyl alcohol) (PVA) were more expanded than DMPC films whereas composite films of DPPC were neither more condensed nor expanded than DPPC films. A polymer impact ratio, P* = pi lipid-polymer/pi lpolymer was calculated and the polymers were ranked in order of their impact on the lipid film. PVA and polysaccharides gave low and high P* values, respectively, corresponding to high and low levels of film interaction, whereas PAA and hydrophobized polysaccharides gave intermediate values, indicating their affinity for and penetration of interfacial films with little disruption of the mono-layer. The results show that measurement of interfacial pressures at the chlorobenzene-water interface might be advantageous for evaluating the action of polymers on biological membranes.
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PMID:An interfacial tension model of the interaction of water-soluble polymers with phospholipid composite monolayers. 933 Jan 96

Ion exchange resins have several applications in pharmacy for controlled or sustained release of drugs. In the present study, effects of the ionic strengths of adsorption medium and dissolution medium on drug adsorption onto and release from a acrylic acid grafted poly(vinylidene fluoride) (PAA-PVDF) were studied. Despite their porosity, PAA-PVDF membranes act reasonable well as cation exchange membranes. It was observed, that ionic strength of adsorption medium, degree of grafting and concentration of propranolol-HCl in adsorption medium affect propranolol-HCl adsorption onto the membrane. The fluxes of smaller molecules (MW < 500) across the membrane decreased with ionic strength of buffer solution, whereas the fluxes of the large molecules (FITC-dextran, MW 4400) increased with ionic strength. Release rate of adsorbed propranolol-HCl from the membrane into phosphate buffer was greatly affected by ionic strength of adsorption medium. These results can be explained by a cation exchange process between membrane and cations present in the buffer solution and swelling behavior of the grafted PAA chains.
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PMID:Influence of ionic strength on drug adsorption onto and release from a poly(acrylic acid) grafted poly(vinylidene fluoride) membrane. 1020 26


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