Ko Aida

Sugar specificity of anti-B hemagglutinin produced by Streptomyces sp

Abstract A hemagglutinin specific for blood group B antigen has been purified to 190-fold from the culture fluid of a strain of Streptomyces sp. by conventional procedure involving ammonium sulfate fractionation and column chromatography. The molecular weight of the partially purified preparation was estimated to be approximately 5000±1000; this value is extremely small as compared with those of hemagglutinins which have been so far isolated from various sources. Hemagglutination-inhibition tests revealed that the Streptomyces agglutinin has a specificity to combine with D-galactose and several saccharides having D-galactose residues at the non-reducing terminal, and that the special configuration of the hydroxyl groups at C-2 and C-4, particularly the hydroxyl group at C-2, is essential for binding of the sugars to the hemagglutinin.

Stereochemical structure recognized by the L-fucose-specific hemagglutinin produced by Streptomyces sp

A hemagglutinin has been purified 4000-fold from the culture filtrate of a strain of Streptomyces by affinity chromatography. The purified preparation was judged to be homogeneous by gel electrophoresis and its molecular weight was estimated to be about 70 000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It may exhibit its full hemagglutinating activity in the monomer form. This hemagglutinin strongly agglutinated human blood group O erythrocytes and was inhibited by L-fucose. It was, however, distinct from the known L-fucose-specific hemagglutinins; first, the hemagglutinating activity of the purified preparation was more than 100-times stronger than that of others; second, D-mannose was a potent inhibitor of this hemagglutinin besides L-fucose but not or scarcely inhibitory to others; and third, p-nitrophenyl-beta-L-fucoside was more inhibitory to this hemagglutinin than p-nitrophenyl-alpha-L-fucoside as opposed to the case of others.

Specific inhibition of viral neuraminidases by an inhibitor, neuraminin, produced by Streptomyces sp.

Abstract Neuraminin was characterized with respect to its inhibition of viral and bacterial neuraminidases. It inhibits the viral but not the bacterial enzymes. In addition, neuraminin distinguishes influenza from Newcastle disease virus. Neuraminin inhibits hydrolysis of fetuin, orosomucoid, and human red blood cell surface glycoproteins by influenza virus or its isolated neuraminidase. The inhibition does not occur when neuraminlactose or colominic acid (a homopolymer of N -acetylneuraminic acid) is used as the substrate. In contrast, neuraminin equally effectively inhibits the action of the Newcastle disease virus toward these substrates. The inhibition was noncompetitive and saturated at a very low concentration of the inhibitor irrespective of the kind and concentration of the substrates.

Incorporation of molecular oxygen during the biosynthesis of ubiquinone in an aerobic bacterium, Pseudomonas desmolytica

Abstract By using 18O2, it was shown that two atoms from atomospheric oxygen are incorporated into a ubiquinone-9 molecule during biosynthesis by Pseudomonas desmolytica . Separate chemical experiments proved that both oxygen atoms in carbonyl groups of the ubiquinone molecule will exchange with water, while the two 18O atoms incorporated do not, in 0.2N HCl at 85°C. These experiments lead to the conclusion that the molecular oxygens are incorporated into two methoxy groups linked to C-5, 6 of the quinone ring. The importance of the cooperative relationship between respiratory system and oxygenation system in oxygen metabolism of bacteria is emphasized.

Conversion of Human Blood Group B and AB Red Blood Cells to Group O and A Cells by Streptomyces Enzyme

Human blood group B and AB cells were converted to O and A active cells, respectively, by treatment with an α-d-galactosidase from Streptomyces 9917S2. Accompanying these conversions a 2 to 8-fold increase was observed in the group H activity on these cells. The conversion reaction proceeded rapidly in phosphate buffered saline without any supplement, Hemolysis, discoloration, and other visible deterioration of the cell were not observed during the process. Conditions for the optimal conversion as well as the susceptibility to the inhibition by sugars were somewhat different from those for the reaction with soluble substrates.

Blood Group Substance-degrading Enzymes Obtained from Streptomyces sp.: Part II. Purification and Characteristics of α-Galactosidase from Streptomyces 9917S2

The blood group B substance-degrading activity of Streptomyces 9917S2 is induced by galactosides as α-galactosidase activity is. Purification of the α-galactosidase was attempted by chromatography on DEAE-Sephadex and Sephadex. The purified preparation was shown to be free from α- and β-glucosidases, β-galactosidase, α- and β-glucosaminidases, and α- and β-galactosaminidases activities. The blood group B substance-degrading activity was present only in this fraction. This enzyme preparation cleaves α-(1→3)- and α-(1→6)-galactosidic linkages. The activity is inhibited by d-galactose, melibiose, and raffinose and also by l-arabinose and d-xylose.

Flocculation of influenza virus by a neuraminidase inhibitor, neuraminin, produced by Streptomyces sp.

Abstract Flocculation of virions by a viral neuraminidase inhibitor, neuraminin, was examined by low speed centrifugation and electron microscopy. The inhibitor could flocculate virions of influenza viruses but not those of Newcastle disease viruses. Virion-free neuraminidase of influenza virus was also flocculated by this inhibitor. The flocculation was temperature dependent and proceeded rapidly over a wide pH range. The amount of the inhibitor required for complete flocculation of virions was similar to that for the maximum inhibition of neuraminidase. Viral neuraminin receptors were stable to various enzymological, physical, and chemical treatments which caused a loss or reduction of the activity of neuraminidase.

Studies on Amino Acid Fermentation:Part XI. Effect of Biotin on the Embden-Meyerhof-Parnas Pathway and the Hexose-Monophosphate Shunt in a Glutamic Acid-Producing Bacterium, Brevibacterium ammoniagenes 317-1

The effect of biotin on glucose catabolism in a l-glutamic acid-producing bacterium, Brevibacterium ammoniagenes, was studied by a modified radiorespirometric method. The amount of glucose metabolized by way of the hexose-monophosphate shunt (HMP) was estimated to be 26% in biotin-deficient cells and 38% in biotin-sufficient cells, respectively. In both cases, the Embden-Meyerhof-Parnas Pathway (EMP) was found to be the major route for glucose catabolism. These results will exclude the present theory at least in our strain that the main route of glucose catabolism is HMP in biotin-deficient cells and EMP in biotin-sufficient ones, and that this is one of the main effect of biotin on l-glutamic acid fermentation.

Distribution of Highly Specific Arylamidase Activities in Bacteria

There are numerous papers on the application of proteolytic enzymes of microbial origin not only in the medical field1} but also in food, leather, detergent, and many other industrial fields.2) Among these enzymes, highly specific ones have attracted great attention in the basic research field as a useful tool for separation, structure analysis, and modification of proteins and peptides.3 ~5) However, systematic studies on the distribution of highly specific peptidases in bacteria have been scarce. We have tried to obtain such peptidases by screening bacteria which can hydrolyze only one substrate out of various amino acid jr?-nitroanilides and amino acid 2naphthylamides, though arylamidase is not always a peptidase6) and vice versa.1}

Blood Group Substance-degrading Enzymes Obtained from Streptomyces sp:Part I. Screening Tests and Culture Conditions for Best Enzyme Production

Various strains of Streptomyces and Aspergillus and several commercial glycosidases were tested for activities of human blood group A and B substance degradation. Five strains of Streptomyces sp. destroyed the serological activity of A substance and 2 strains of the same genus destroyed B substance. In Streptomyces 9917S2, the strongest decomposer of B substance, the activity of B substance degradation was induced by galactose, lactose, raffinose, and melibiose. Fructose, inulin, maltose, and glucosamine also acted as inducers. Culture broth of this organism has the activities of α- and β-galactosidases and β-N-acetyl-glucosaminidase. Activities of α- and β-glucosidases, β-N-acetyl-glucosaminidase, and α- and β-N-acetyl-galactosaminidases were not detected. Characteristics of blood group substance degradation by this organism were discussed in relation to glycosidases present in this organism.