Improving the growth response ofBorreliaspecies

1995 ◽  
Vol 41 (11) ◽  
pp. 1031-1034 ◽  
Author(s):  
Penelope J. Padgett ◽  
Mary J. Golden ◽  
David J. Pekala

Borrelia species are microaerophilic spirochetes, i.e., they are unable to grow in the presence of atomospheric oxygen (21%) or under anaerobic conditions. Compounds that have been shown to quench toxic products of oxygen (i.e., superoxide radicals, hydrogen peroxide, hydroxyl radicals, and singlet oxygen) were added to Borrelia growth media (Kelly's medium). Among the compounds tested were catalase, superoxide dismutase, peroxidase, dithiothreitol (DTT), formate, fumarate, dimethyl sulfoxide (DMSO), manganese, activated charcoal (Norit A), mannitol, and a combination of ferric chloride and potassium (meta)bisulfite (iron-bisulfite). Of these, the compounds that were the most effective in enhancing the growth of the species of Borrelia tested were iron-bisulfite, DTT, and DMSO. DTT possesses the ability to break down hydrogen peroxide, and iron-bisulfite has been reported to have superoxide dismutase-like activity in artificial media. Iron-bisulfite, DMSO, sodium formate, DTT, and combinations of these compounds have been incorporated into solid and biphasic Kelley's medium to determine their effect on microaerobic and aerobic growth on plates and in biphasic medium. Iron-bisulfite was the most effective compound tested under these conditions.Key words: Borrelia, bisulfite, spirochetes, microaerobe.

1988 ◽  
Vol 251 (3) ◽  
pp. 893-899 ◽  
Author(s):  
H Iwahashi ◽  
T Ishii ◽  
R Sugata ◽  
R Kido

Superoxide dismutase (SOD) enhanced the formation of hydroxyl radicals, which were detected by using the e.s.r. spin-trapping technique, in a reaction mixture containing 3-hydroxyanthranilic acid (or p-aminophenol), Fe3+ ions, EDTA and potassium phosphate buffer, pH 7.4. The hydroxyl-radical formation enhanced by SOD was inhibited by catalase and desferrioxamine, and stimulated by EDTA and diethylenetriaminepenta-acetic acid, suggesting that both hydrogen peroxide and iron ions participate in the reaction. The hydroxyl-radical formation enhanced by SOD may be considered to proceed via the following steps. First, 3-hydroxyanthranilic acid is spontaneously auto-oxidized in a process that requires molecular oxygen and yields superoxide anions and anthranilyl radicals. This reaction seems to be reversible. Secondly, the superoxide anions formed in the first step are dismuted by SOD to generate hydrogen peroxide and molecular oxygen, and hence the equilibrium in the first step is displaced in favour of the formation of superoxide anions. Thirdly, hydroxyl radicals are generated from hydrogen peroxide through the Fenton reaction. In this Fenton reaction Fe2+ ions are available since Fe3+ ions are readily reduced by 3-hydroxyanthranilic acid. The superoxide anions do not seem to participate in the reduction of Fe3+ ions, since superoxide anions are rapidly dismuted by SOD present in the reaction mixture.


1977 ◽  
Vol 163 (3) ◽  
pp. 441-448 ◽  
Author(s):  
B Halliwell

1. Dihydroxyfumarate slowly autoxidizes at pH6. This reaction is inhibited by superoxide dismutase but not by EDTA. Mn2+ catalyses dihydroxyfumarate oxidation by reacting with O2 leads to to form Mn3+, which seems to oxidize dihydrofumarate rapidly. Cu2+ also catalyses dihydroxyfumarate oxidation, but by a mechanism that does not involve O2 leads to. 2. Peroxidase catalyses oxidation of dihydroxyfumarate at pH6; addition of H2O2 does not increase the rate. Experiments with superoxide dismutase and catalase suggest that there are two types of oxidation taking place: an enzymic, H2O2-dependent oxidation of dihydroxyfumarate by peroxidase, and a non-enzymic reaction involving oxidation of dihydroxyfumarate by O2 leads to. The latter accounts for most of the observed oxidation of dihydroxyfumarate. 3. During dihydroxyfumarate oxidation, most peroxidase is present as compound III, and the enzymic oxidation may be limited by the low rate of breakdown of this compound. 4. Addition of p-coumaric acid to the peroxidase/dihydroxyfumarate system increases the rate of dihydroxyfumarate oxidation, which is now stimulated by addition of H2O2, and is more sensitive to inhibition by catalase but less sensitive to superoxide dismutase. Compound III is decomposed in the presence of p-coumaric acid. p-Hydroxybenzoate has similar, but much smaller, effects on dihydroxyfumarate oxidation. However, salicylate affects neither the rate nor the mechanism of dihydroxyfumarate oxidation. 5. p-Hydroxybenzoate, salicylate and p-coumarate are hydroxylated by the peroxidase/dihydroxyfumarate system. Experiments using scavengers of hydroxyl radicals shown that OH is required. Ability to increase dihydroxyfumarate oxidation is not necessary for hydroxylation to occur.


1977 ◽  
Vol 6 (2) ◽  
pp. 117-123
Author(s):  
Fred Frölander ◽  
Jan Carlsson

Peptostreptococcus anaerobius strain VPI 4330-1 was used as the test organism in an evaluation of the bactericidal effect of anaerobic broth exposed to air. The test organism, grown under anaerobic conditions in Trypticase soy broth, was diluted in buffered salt solution, and about 2 × 10 4 cells were suspended in 10 ml of an aerated broth. Ninety percent of the cells were killed within 15 min in actinomyces broth and within 50 min in Trypticase soy broth. All cells survived for 2 h in fluid thioglycolate medium. Addition of DABCO [1,4-diazabicyclo (2.2.2) octane] or mannitol to Trypticase soy broth did not influence the death rate of the organism, whereas superoxide dismutase decreased the death rate. Addition of catalase or manganese dioxide to the broth kept all the cells viable for 2 h. Of the three broth media tested, actinomyces broth reduced oxygen at the highest rate and Trypticase soy broth reduced it at the slowest rate. Hydrogen peroxide could be demonstrated in actinomyces broth and in Trypticase soy broth but not in fluid thioglycolate medium. In addition to catalase, manganese dioxide also removed all hydrogen peroxide from Trypticase soy broth, and superoxide dismutase significantly decreased the concentration of hydrogen peroxide in the broth. The results suggest that hydrogen peroxide mediated the toxic effect of atmospheric oxygen in these broth media.


1997 ◽  
Vol 345 (1) ◽  
pp. 156-159 ◽  
Author(s):  
R. Gabbianelli ◽  
A. Battistoni ◽  
C. Capo ◽  
F. Polticelli ◽  
G. Rotilio ◽  
...  

1997 ◽  
Vol 6 (5-6) ◽  
pp. 369-374
Author(s):  
Y. Oyanagui

Anti-inflammatory actions of two anti-allergic drugs, alone or with dexamethasone (Dex) were examined in two models, because inflammation is claimed to be important for allergic events, especially for asthma. Cromoglycate and nedocromil were tested in ischaemic- and histamineinduced paw oedema models of mice. These antiallergic drugs (1–100 mg/kg, i.p.) failed to suppress these oedemata, but enhanced the suppressions by a low dose of dexamethasone (0.1 mg/kg, s.c.) at 3–8 h after Dex injection. The mode of effects by anti-allergic drugs resembled that of a natural antioxidant (α-tocopherol, β-carotene etc.), and was different from that of an immunosuppressant like FK506. The enhancing potencies of the two anti-allergic drugs were similar at 6 h after Dex in both oedemata, and were diminished by superoxide dismutase (SOD) or catalase (i.p.). Cycloheximide completely abolished suppressions. Nedocromil, but not cromoglycate, inhibits inflammatory events. Therefore, there are common unknown actions by which the two anti-allergics enhance suppression by Dex. A possible mechanism of this action was supposed to enhance the superoxide and/or hydrogen peroxide-dependent glucocorticoid receptor (GR) signalling in the target cells.


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