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B Reiter

Publications and source records attributed to B Reiter.

53 records · Page 3Linked to original sources
PubMed1972

Common antigenic determinant in a rumen organism and in salmonellae containing the antigen O4.

Nineteen of 28 strains of rumen organisms isolated from a cow on a high roughage diet and identified morphologically as butyrivibrios, reacted to a low agglutinin titer with salmonella antisera, forming five groups. However only one strain reacted with polyvalent O salmonella antiserum. This strain reacted with O4 factor serum and with antisera to Salmonella strains containing the antigen O4, and agglutinin absorption tests showed the presence of an antigen identical to O4. When 16 further strains of butyrivibrio-like rumen organisms isolated from three cows and one steer were examined, one possessed an antigen similar to but not identical with the antigen O9, and two strains reacted with specific O6,7 factor serum but were not examined further. These four strains were presumptively identified by physiological tests as butyrivibrios. The possible site of antigenic stimulation by such organisms is discussed.

Absorption↗
PubMed1966

The inhibition of streptococci by lactoperoxidase, thiocyanate and hydrogen peroxide. The effect of the inhibitory system on susceptible and resistant strains of group N streptococci.

1. The growth of the lactoperoxidase-sensitive Streptococcus cremoris 972 in a synthetic medium was inhibited by lactoperoxidase and thiocyanate. The glycolysis and oxygen uptake of suspensions of Strep. cremoris 972 in glucose or lactose were also inhibited. The lactoperoxidase-resistant Strep. cremoris 803 was not inhibited under these conditions but was inhibited in the absence of a source of energy. 2. Lactoperoxidase (EC 1.11.1.7), thiocyanate and hydrogen peroxide completely inhibited the hexokinases of non-metabolizing suspensions of both strains. The inhibition was reversible, hexokinase and glycolytic activities of Strep. cremoris 972 being restored by washing the cells free from inhibitor. The aldolase and 6-phosphogluconate-dehydrogenase activities of Strep. cremoris 972 were partially inhibited but several other enzymes were unaffected. 3. The resistance of Strep. cremoris 803 to inhibition was not due to the lack of hydrogen peroxide formation, to the destruction of peroxide, to the inactivation of lactoperoxidase or to the operation of alternative pathways of carbohydrate metabolism. 4. A ;reversal factor', which was partially purified from extracts of Strep. cremoris 803, reversed the inhibition of glycolysis of Strep. cremoris 972. The ;reversal factor' also catalysed the oxidation of NADH(2) in the presence of an intermediate oxidation product of thiocyanate and was therefore termed the NADH(2)-oxidizing enzyme. 5. The NADH(2)-oxidizing enzyme was present in lactoperoxidase-resistant streptococci but was absent from lactoperoxidase-sensitive streptococci.

Carbohydrate Metabolism↗
PubMed1966

The inhibition of streptococci by lactoperoxidase, thiocyanate and hydrogen peroxide. The oxidation of thiocyanate and the nature of the inhibitory compound.

1. The products of the lactoperoxidase-catalysed oxidation of thiocyanate by hydrogen peroxide were sulphate, carbon dioxide and ammonia. Cyanate, sulphite and a compound showing increased extinction at 235mmu (the ;235 compound') were intermediate oxidation products. 2. Two of the intermediates acted as electron acceptors in the oxidation of NADH(2). Thus NADH(2) was oxidized by sulphite in the presence of lactoperoxidase (EC 1.11.1.7) and Mn(2+) and by the ;235 compound' in the presence of an enzyme, the NADH(2)-oxidizing enzyme, present in extracts of lactoperoxidase-resistant streptococci. Sulphur dicyanide also acted as an electron acceptor in the latter reaction. The ;235 compound' was also reduced non-enzymically by sulphite. 3. The glycolysis of lactoperoxidasesensitive streptococci suspended in glucose solution was not inhibited by sulphite, cyanate, cyanide or the ;235 compound' but was inhibited by sulphur dicyanide. The inhibition by 0.1mm-sulphur dicyanide could be reversed, as could that caused by lactoperoxidase, thiocyanate and hydrogen peroxide, by washing the cells or by the addition of a cell-free extract of a lactoperoxidase-resistant streptococcus. 4. The effects of 0.1mm-sulphur dicyanide on catabolic enzymes of resting streptococci were very similar to those of the lactoperoxidase-thiocyanate-hydrogen peroxide system. Thus hexokinase was completedly inhibited, glucose 6-phosphate dehydrogenase and aldolase were partially inhibited and phosphohexokinase was little affected in both cases.

Autoradiography↗
PubMedDate not supplied

The lactoperoxidase-thiocyanate-hydrogen peroxide antibacterium system.

Lactoperoxidase present in various secretions oxidizes thiocyanate (SCN-) in the presence of H2O2 to an unstable oxidation product--hypothiocyanite (OSCN-), which is bactericidal for enteric pathogens including multiple antibiotic resistant strains of E. coli. The system damages the inner membrane causing leakage and cessation of uptake of nutrient, leading eventually to death of the organisms and lysis. The possible involvement of O2- and 1O2 is discussed.

Animals↗