Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.1.14 (SPS)
 813 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By using trypsin-treated human type O cells as indicators, we compared the abilities of four polyanion-divalent cation combinations (heparin-MnCl(2); high-and low-molecular-weight dextran sulfate-CaCl(2); and sodium polyanetholesulfonate [SPS]-CaCl(2)) for removal of serum non-immunoglobulin (lipoprotein) inhibitors of rubella hemagglutination. The combination of SPS-CaCl(2) was found to be the most effective, precipitating completely the pre-beta and beta-lipoproteins and reducing the alpha-lipoprotein levels by more than 50%. Hemagglutination patterns after this treatment were clear and stable, and, when normal sera were tested, hemagglutination-inhibition (HI) titers were comparable to those obtained after standard heparin-MnCl(2) treatment. High-molecular-weight dextran sulfate-CaCl(2) removed serum lipoproteins almost as effectively as SPS-CaCl(2). However, problems of nonspecific agglutination and the heavy hemagglutination patterns resulting made this combination unacceptable for routine purposes. Neither low-molecular-weight dextran sulfate-CaCl(2) nor heparin-MnCl(2) removed the pre-beta lipoproteins completely, and occasionally traces of beta-lipoprotein also remained after treatment. The presence of pre-beta lipoproteins in normal sera after treatment may be of no consequence in the HI test since we have found that the very-low-density lipoprotein fractions obtained by ultracentrifugal methods from normal sera (those corresponding to the pre-beta fractions obtained by electrophoresis) had no HI activity. However, very-low-density lipoprotein fractions from all hyperlipemic sera tested had HI activity (titers ranging from 1:16 to 1:1,024) which, in the majority of cases, was not eliminated after heparin-MnCl(2) treatment. In every case, treatment with SPS-CaCl(2) removed this nonspecific activity completely. Since hyperlipemic sera may occasionally be encountered in routine rubella HI antibody testing, we recommend the use of SPS-CaCl(2) rather than heparin-MnCl(2) for pretreatment of sera.
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PMID:Use of sodium polyanetholesulfonate-CaCl2 for removal of serum nonspecific inhibitors of rubella hemagglutination: comparison with other polyanion-divalent cation combinations. 19 14

Loop residues in domain II of Bacillus thuringiensis Cry delta-endotoxins have been demonstrated to be involved in insecticidal specificity. In this study, selected residues in loops beta6-beta7 (S(387)SPS(390)), beta8-beta9 (S(410), N(411), T(413), T(415), E(417) and G(418)) and beta10-beta11 (D(454)YNS(457)) in domain II of the Cry4Ba mosquito-larvicidal protein were changed individually to alanine by PCR-based directed mutagenesis. All mutant toxins were expressed in Escherichia coli JM109 cells as 130-kDa protoxins at levels comparable to the wild type. Only E. coli cells that express the P389A, S410A, E417A, Y455A or N456A mutants exhibited a loss in toxicity against Aedes aegypti mosquito larvae of approximately 30% when compared to the wild type. In addition, E. coli cells expressing double mutants, S410A/E417A or Y455A/N456A, at wild-type levels revealed a significantly higher loss in larvicidal activity of approximately 70%. Similar to the wild-type protoxin, both double mutant toxins were structurally stable upon solubilisation and trypsin activation in carbonate buffer, pH 9.0. These results indicate that S(410) and E(417) in the beta8-beta9 loop, and Y(455) and N(456) in the beta10-beta11 loop are involved in larvicidal activity of the Cry4Ba toxin.
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PMID:Targeted mutagenesis of loop residues in the receptor-binding domain of the Bacillus thuringiensis Cry4Ba toxin affects larvicidal activity. 1562 55