scholarly journals Hydrogen Peroxide Production in Streptococcus pyogenes: Involvement of Lactate Oxidase and Coupling with Aerobic Utilization of Lactate

2004 ◽  
Vol 186 (7) ◽  
pp. 2046-2051 ◽  
Author(s):  
Masanori Seki ◽  
Ken-ichiro Iida ◽  
Mitsumasa Saito ◽  
Hiroaki Nakayama ◽  
Shin-ichi Yoshida
Keyword(s):  
Streptococcus Pyogenes ◽  
Oxidase Activity ◽  
Nadh Oxidase ◽  
Soluble Fraction ◽  
The Other ◽  
Significant Activity ◽  
Lactate Oxidase ◽  
Permeabilized Cells ◽  
A Subunit

ABSTRACT Streptococcus pyogenes strains can be divided into two classes, one capable and the other incapable of producing H2O2 (M. Saito, S. Ohga, M. Endoh, H. Nakayama, Y. Mizunoe, T. Hara, and S. Yoshida, Microbiology 147:2469-2477, 2001). In the present study, this dichotomy was shown to parallel the presence or absence of H2O2-producing lactate oxidase activity in permeabilized cells. Both lactate oxidase activity and H2O2 production under aerobic conditions were detectable only after glucose in the medium was exhausted. Thus, the glucose-repressible lactate oxidase is likely responsible for H2O2 production in S. pyogenes. Of the other two potential H2O2-producing enzymes of this bacterium, NADH and α-glycerophosphate oxidase, only the former exhibited low but significant activity in either class of strains. This activity was independent of the growth phase, suggesting that the protein may serve in vivo as a subunit of the H2O2-scavenging enzyme NAD(P)H-linked alkylhydroperoxide reductase. The activity of lactate oxidase was associated with the membrane while that of NADH oxidase was in the soluble fraction, findings consistent with their respective physiological roles, i.e., the production and scavenging of H2O2. Analyses of fermentation end products revealed that the concentration of lactate initially increased with time and decreased on glucose exhaustion, while that of acetate increased during the culture. These results suggest that the lactate oxidase activity of H2O2-producing cells oxidizes lactate to pyruvate, which is in turn converted to acetate. This latter process proceeds presumably via acetyl coenzyme A and acetyl phosphate with formation of extra ATP.

scholarly journals Studies on Sulfhydryl Groups during Cell Division of Sea Urchin Egg

1962 ◽  
Vol 45 (3) ◽  
pp. 427-438 ◽  
Author(s):  
Hikoichi Sakai
Keyword(s):  
Cell Division ◽  
Sea Urchin ◽  
Soluble Fraction ◽  
Water Soluble ◽  
The Other ◽  
Original Sample ◽  
Water Soluble Fraction ◽  
Sea Urchin Egg ◽  
Soluble Fractions

The contractility of the thread model prepared from the KCl-soluble proteins of the egg and in vivo factors for the contraction are investigated in Hemicentrotus, Anthocidaris, and Pseudocentrotus eggs. The contractility of the thread model induced by metal ions or cystine changes during development in the characteristic pattern of high at the metaphase and low at the monaster and the interkinetic stages. The change in contractility is paralleled by the change in the —SH content of the protein. The water-soluble fraction of the eggs has activity in causing contraction of the thread model. This activity changes during development in the same way as the contractility itself. The contraction of the thread induced by the water-soluble fractions is accompanied by a decrease in the —SH content of the thread. The activity of the water-soluble fraction in inducing the contraction is proportional to its ability to decrease the number of —SH groups. On boiling, the activity is largely destroyed. The activity is due to two components, one being non-dialyzable and the other dialyzable. Separately each component has little effect, but when mixed, the activity of the original sample is completely restored.

scholarly journals Identification of bioactive compounds from Fraxinus angustifolia extracts with anti-NADH oxidase activity of bovine milk xanthine oxidoreductase

2019 ◽  
pp. 133-147 ◽  
Author(s):  
Nadjia AHMANE ◽  
Dina ATMANI-KILANI ◽  
Nassima CHAHER ◽  
Karima AYOUNI ◽  
Meriem RAHMANI-BERBOUCHA ◽  
...  
Keyword(s):  
Oxidase Activity ◽  
Nadh Oxidase ◽  
Bovine Milk ◽  
Ros Generation ◽  
Xanthine Oxidoreductase ◽  
Fraxinus Angustifolia ◽  
Activity Of Enzymes ◽  
Nadh Oxidase Activity

Fraxinus angustifolia leaves and bark are used in traditional medicine against various inflammatory-related pathologies incumbent to reactive oxygen species (ROS) generation by the NADH oxidase activity of enzymes such as xanthine oxidoreductase (XOR). This study was designed to investigate the in vitro and in vivo inhibitory activities of this enzyme by Fraxinus angustifolia extracts. The leaf organic phase of ethyl acetate (LFA) and its bark aqueous counterpart (BFA) showed the strongest anti-NADH oxidase activity in vitro (IC50 = 38.51 and 42.04 μg mL-1, respectively). They consequently suppressed superoxide generation both enzymatically (53% and 19%, respectively) and nonenzymatically (34% and 19%, respectively). These results were corroborated in vivo, with high anti- NADH oxidase potential of the leaves and bark extracts (75.32% and 51.32%, respectively) concomitant with moderate hypouricemic activities (36.84% and 38.59%, respectively). Bio-guided fractionation led to the identification, by LC-DAD-MS/MS, of esculin and calcelarioside in bark and kaempferol glucoside in leaves as the main compounds responsible for the anti-NADH oxidase activity of XOR. These results plead in favor of the use of F. angustifolia as a source of potentially interesting therapeutic substances.

scholarly journals Simultaneous isolation of emm89-type Streptococcus pyogenes strains with a wild-type or mutated covS gene from a single streptococcal toxic shock syndrome patient

2014 ◽  
Vol 63 (4) ◽  
pp. 504-507 ◽  
Author(s):  
Katsuaki Masuno ◽  
Ryo Okada ◽  
Yan Zhang ◽  
Masanori Isaka ◽  
Ichiro Tatsuno ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Amino Acid ◽  
Knee Joint ◽  
Streptococcus Pyogenes ◽  
Toxic Shock Syndrome ◽  
The Other ◽  
Streptococcal Toxic Shock Syndrome ◽  
Upper Respiratory Tract ◽  
Toxic Shock

Streptococcal toxic shock syndrome (STSS) is a re-emerging infectious disease in many developed countries. Recent studies have suggested that mutations in CovRS, a two-component regulatory system in Streptococcus pyogenes, play important roles in the pathogenesis of STSS. However, in vivo evidence of the significance of CovRS in human infections has not been fully demonstrated. We investigated five S. pyogenes strains isolated simultaneously from the pharynx, sputum, knee joint, cerebrospinal fluid and blood of a single STSS patient. All were emm89-type strains, and multilocus sequence typing (MLST) analysis revealed that the strains of pharynx and blood were isogenic. The growth rates of the strains from pharynx and sputum were faster than those of the other strains. Protein profiles of the culture supernatants of strains from the pharynx and sputum were also different from those of the other strains. Sequence analyses revealed that strains from the knee joint, cerebrospinal fluid and blood contained a single nucleotide difference in the covS coding region, resulting in one amino acid change, compared with the other strains. Introduction of a plasmid containing the covS gene from the pharynx strain to the blood strain increased the production of SpeB protein. This suggests that the one amino acid alteration in CovS was relevant to pathogenesis. This report supports the idea that mutated CovS plays important roles in vivo in the dissemination of S. pyogenes from the upper respiratory tract of human to aseptic tissues such as blood and cerebrospinal fluid.

scholarly journals H2O2Production in Species of the Lactobacillus acidophilus Group: a Central Role for a Novel NADH-Dependent Flavin Reductase

2014 ◽  
Vol 80 (7) ◽  
pp. 2229-2239 ◽  
Author(s):  
Rosanne Hertzberger ◽  
Jos Arents ◽  
Henk L. Dekker ◽  
R. David Pridmore ◽  
Christof Gysler ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Lactobacillus Acidophilus ◽  
Nadh Oxidase ◽  
Reductase Activity ◽  
Bacterial Species ◽  
Flavin Mononucleotide ◽  
Flavin Reductase ◽  
Lactate Oxidase ◽  
Content Type

ABSTRACTHydrogen peroxide production is a well-known trait of many bacterial species associated with the human body. In the presence of oxygen, the probiotic lactic acid bacteriumLactobacillus johnsoniiNCC 533 excretes up to 1 mM H2O2, inducing growth stagnation and cell death. Disruption of genes commonly assumed to be involved in H2O2production (e.g., pyruvate oxidase, NADH oxidase, and lactate oxidase) did not affect this. Here we describe the purification of a novel NADH-dependent flavin reductase encoded by two highly similar genes (LJ_0548andLJ_0549) that are conserved in lactobacilli belonging to theLactobacillus acidophilusgroup. The genes are predicted to encode two 20-kDa proteins containing flavin mononucleotide (FMN) reductase conserved domains. Reductase activity requires FMN, flavin adenine dinucleotide (FAD), or riboflavin and is specific for NADH and not NADPH. TheKmfor FMN is 30 ± 8 μM, in accordance with its proposedin vivorole in H2O2production. Deletion of the encoding genes inL. johnsoniiled to a 40-fold reduction of hydrogen peroxide formation. H2O2production in this mutant could only be restored by intranscomplementation of both genes. Our work identifies a novel, conserved NADH-dependent flavin reductase that is prominently involved in H2O2production inL. johnsonii.

scholarly journals The NADH oxidase system (external) of muscle mitochondria and its role in the oxidation of cytoplasmic NADH

1985 ◽  
Vol 229 (3) ◽  
pp. 631-641 ◽  
Author(s):  
U F Rasmussen ◽  
H N Rasmussen
Keyword(s):  
Oxidase Activity ◽  
Nadh Oxidase ◽  
Specific Activity ◽  
Reductase Activity ◽  
Heart Mitochondria ◽  
Freezing And Thawing ◽  
Oxidase System ◽  
Muscle Mitochondria ◽  
Nadh Oxidase Activity

An exo-NADH oxidase system [NADH oxidase system (external)], effecting intact-mitochondrial oxidation of added NADH, was studied in pigeon heart mitochondria. Breast muscle mitochondria showed an equal specific activity of the system. The exo-NADH oxidase activity (200 micron mol of NADH/min per g of protein) equalled two-thirds of the State-3 respiratory activity with malate + pyruvate or one-seventh of the total NADH oxidase activity of heart mitochondria. The activity was not caused by use of proteinase in the preparation procedure and all measured parameters were very reproducible from preparation to preparation. The activity is therefore most likely not due to preparation artefacts. The exo-NADH oxidase system is present in all mitochondria in the preparation and is not confined to a subpopulation. The system reduced all cytochrome anaerobically and direct interaction with all cytochrome oxidase was demonstrated by interdependent cyanide inhibition. The exo-NADH oxidase system seems to be located at the outer surface of the mitochondrial inner membrane because, for instance, only this system was rapidly inhibited by rotenone, and ferricyanide could act as acceptor in the rotenone-inhibited system (reductase activity = 20 times oxidase activity). In the presence of antimycin, added NADH reduced only a part of the b-cytochromes. Freezing and thawing the mitochondria, one of the methods used for making them permeable to NADH, destroyed this functional compartmentation. The characteristics of the exo-NADH oxidase system and the malate-aspartate shuttle are compared and the evidence for the shuttle's function in heart in vivo is re-evaluated. It is proposed that oxidation of cytoplasmic NADH in red muscles primarily is effected by the exo-NADH oxidase system.

scholarly journals Effect of Different NADH Oxidase Levels on Glucose Metabolism by Lactococcus lactis: Kinetics of Intracellular Metabolite Pools Determined by In Vivo Nuclear Magnetic Resonance

2002 ◽  
Vol 68 (12) ◽  
pp. 6332-6342 ◽  
Author(s):  
Ana Rute Neves ◽  
Ana Ramos ◽  
Helena Costa ◽  
Iris I. van Swam ◽  
Jeroen Hugenholtz ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Glucose Metabolism ◽  
Lactococcus Lactis ◽  
Oxidase Activity ◽  
Nadh Oxidase ◽  
Glycolytic Flux ◽  
Aerobic Conditions ◽  
Nadh Oxidase Activity

ABSTRACT Three isogenic strains of Lactococcus lactis with different levels of H2O-forming NADH oxidase activity were used to study the effect of oxygen on glucose metabolism: the parent strain L. lactis MG1363, a NOX− strain harboring a deletion of the gene coding for H2O-forming NADH oxidase, and a NOX+ strain with the NADH oxidase activity enhanced by about 100-fold. A comprehensive description of the metabolic events was obtained by using 13C nuclear magnetic resonance in vivo. The most noticeable results of this study are as follows: (i) under aerobic conditions the level of fructose 1,6-bisphosphate [Fru(1,6)P2] was lower than the level under anaerobic conditions, and the rate of Fru(1,6)P2 depletion was very high; (ii) the levels of 3-phosphoglycerate and phosphoenolpyruvate were considerably enhanced under aerobic conditions and significantly lower in the NOX− strain; and (iii) the glycolytic flux decreased in the presence of saturating levels of oxygen, but it was not altered in response to changes in the NADH oxidase activity. In particular, the observation that the glycolytic flux was not enhanced in the NOX+ strain indicated that glycolytic flux was not primarily determined by the level of NADH in the cell. The patterns of end products were identical for the NOX− and parent strains; in the NOX+ strain the carbon flux was diverted to the production of α-acetolactate-derived compounds, and at a low pH this strain produced diacetyl at concentrations up to 1.6 mM. The data were integrated with the goal of identifying the main regulatory aspects of glucose metabolism in the presence of oxygen.

scholarly journals Murine Vaginal Colonization Model for Investigating Asymptomatic Mucosal Carriage of Streptococcus pyogenes

2013 ◽  
Vol 81 (5) ◽  
pp. 1606-1617 ◽  
Author(s):  
Michael E. Watson ◽  
Hailyn V. Nielsen ◽  
Scott J. Hultgren ◽  
Michael G. Caparon
Keyword(s):  
Streptococcus Pyogenes ◽  
Critical Role ◽  
Protein A ◽  
Vaginal Fluid ◽  
Vaginal Mucosa ◽  
Lactate Oxidase ◽  
Content Type ◽  
Vaginal Colonization ◽  
Colonization Model

ABSTRACTWhile many virulence factors promotingStreptococcus pyogenesinvasive disease have been described, specific streptococcal factors and host properties influencing asymptomatic mucosal carriage remain uncertain. To address the need for a refined model of prolongedS. pyogenesasymptomatic mucosal colonization, we have adapted a preestrogenized murine vaginal colonization model forS. pyogenes. In this model, derivatives of strains HSC5, SF370, JRS4, NZ131, and MEW123 established a reproducible, asymptomatic colonization of the vaginal mucosa over a period of typically 3 to 4 weeks' duration at a relatively high colonization efficiency. Prior treatment with estradiol prolonged streptococcal colonization and was associated with reduced inflammation in the colonized vaginal epithelium as well as a decreased leukocyte presence in vaginal fluid compared to the levels of inflammation and leukocyte presence in non-estradiol-treated control mice. The utility of our model for investigatingS. pyogenesfactors contributing to mucosal carriage was verified, as a mutant with a mutation in the transcriptional regulator catabolite control protein A (CcpA) demonstrated significant impairment in vaginal colonization. An assessment ofin vivotranscriptional activity in the CcpA−strain for several known CcpA-regulated genes identified significantly elevated transcription of lactate oxidase (lctO) correlating with excessive generation of hydrogen peroxide to self-lethal levels. Deletion oflctOdid not impair colonization, but deletion oflctOin a CcpA−strain prolonged carriage, exceeding even that of the wild-type strain. Thus, while LctO is not essential for vaginal colonization, its dysregulation is deleterious, highlighting the critical role of CcpA in promoting mucosal colonization. The vaginal colonization model should prove effective for future analyses ofS. pyogenesmucosal colonization.

scholarly journals RESPIRATION AND PROTEIN SYNTHESIS IN ESCHERICHIA COLI MEMBRANE-ENVELOPE FRAGMENTS

1972 ◽  
Vol 55 (2) ◽  
pp. 266-281 ◽  
Author(s):  
Richard W. Hendler ◽  
Amelia H. Burgess
Keyword(s):  
Escherichia Coli ◽  
Nicotinamide Adenine Dinucleotide ◽  
Oxidase Activity ◽  
Nadh Oxidase ◽  
Molecular Size ◽  
Reduced Form ◽  
Lactate Oxidase ◽  
Membrane Envelope ◽  
Nadh Oxidase Activity ◽  
Sepharose 4B

Membranes obtained from Escherichia coli have been solubilized with deoxycholate. The solubilized dehydrogenases and cytochromes are not sedimented at 105,000 g. These components readily penetrate the "included space" of Sepharose 4B (Pharmacia Fine Chemicals Inc., Uppsala, Sweden) and polyacrylamide gels and have been fractionated on the basis of molecular size. Solubilization destroys nicotinamide adenine dinucleotide, reduced form (NADH) oxidase and D-lactate oxidase activities, but leaves an appreciable part of the original succinoxidase activity intact. Evidence for a succinate dehydrogenase-cytochrome b1 complex is given. Menadione added to the solubilized preparation does not elicit NADH oxidase activity nor stimulate the existing succinoxidase activity, but does provoke an active D-lactate oxidase activity. This D-lactate oxidase activity, however, does not use cytochromes and is not sensitive to cyanide.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

Tonsillar Inflammation, a Rare Cause of Bradycardia and Hypotension

2018 ◽  
Vol 3 (3) ◽  
Keyword(s):  
Streptococcus Pyogenes ◽  
Fusobacterium Necrophorum ◽  
Outpatient Setting ◽  
Peritonsillar Abscess ◽  
The Other ◽  
Streptococcus Group ◽  
Other Hand ◽  
Group A

Tonsillitis is a frequently encountered pathology in the outpatient setting, usually caused by viruses [1]. When bacterial, the most common causatory microbe is streptococcus group A [1]. Tonsillar and peritonsillar abscess (PTA) on the other hand are never viral, and are usually caused by streptococcus pyogenes, Streptococcus melleri, fusobacterium necrophorum and staphylococci [1,2]. The overall incidence of PTA is suggested to be 37/100,000 patients, with the highest incidence between ages 14-21 at 124/100,000 [3].

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