Impact of growth conditions and role of sigB on Listeria monocytogenes fitness in single and mixed biofilms cultured with Lactobacillus plantarum
Saa Ibusquiza, P. ; Nierop Groot, M.N. ; Deban Valles, A. ; Abee, T. ; Besten, H.M.W. den - \ 2015
Food Research International 71 (2015). - ISSN 0963-9969 - p. 140 - 145.
lactic-acid bacteria - oxidative stress resistance - gram-positive bacteria - superoxide-dismutase - tolerance response - arginine deiminase - species biofilms - stainless-steel - sodium-chloride - sigma(b)
The role of sigB, a major transcriptional regulator of stress response genes, was assessed in formation of single and mixed species biofilms of Listeria monocytogenes EGD-e and Lactobacillus plantarum WCFS1 as secondary species at 20 °C and 30 °C using different medium compositions (nutrient-rich medium with and without supplementary manganese, glucose and salt). L. monocytogenes showed significant biofilm development at both temperatures and in all media tested although less biofilm was formed when glucose was supplemented only. The contribution of L. monocytogenes to the mixed species biofilm declined especially at higher temperature in glucose-rich medium in the absence and presence of manganese, due to lactic acid formation with concomitant decrease in culture pH below the pHmin of L. monocytogenes. Using an in-frame sigB deletion mutant and a complementation mutant we showed that sigB contributed to survival under these acid stress conditions. Notably, the additional presence of salt protected L. monocytogenes in the acidic mixed species biofilms resulting in an increase of around 2–3 log10 cfu/ml and this phenomenon showed to be sigB-dependent.
The effect of endogenous hydrogen peroxide induced by cold treatment in the improvement of tissue regeneration efficiency
Szechynska-Hebda, M. ; Skrzypek, E. ; Dabrowska, G. ; Wedzony, M. ; Lammeren, A.A.M. van - \ 2012
Acta Physiologiae Plantarum 34 (2012)2. - ISSN 0137-5881 - p. 547 - 560.
oxidative stress - somatic embryogenesis - ascorbate peroxidase - superoxide-dismutase - gene-expression - anther culture - plant-regeneration - winter-wheat - bread wheat - protoplasts
We propose that oxidative stress resulting from an imbalance between generation and scavenging hydrogen peroxide contributes to tissue regeneration efficiency during somatic embryogenesis of hexaploid winter wheat (Triticum aestivum cv. Kamila) and organogenesis of faba bean (Vicia faba ssp. minor cv. Nadwislanski). Endogenous hydrogen peroxide content and antioxidant capacity of cells were determined in initial explants and callus cultures derived from these explants. Regeneration-competent explants (immature embryos) contained more endogenous H2O2 than explants initiated from regeneration-recalcitrant tissue (mature wheat embryos and faba bean epicotyls). Higher H2O2 levels were observed despite the higher activity of antioxidative enzymes (superoxide dismutase and catalase) and the induction of their gene expression. Calli originating from immature embryos retained the capacity of the initial explants: high H2O2 production was observed during the whole culture period. Low temperature treatment (4°C) was found to be an effective factor, which improved both regeneration ability and H2O2 production. Exogenous application to the medium of H2O2 and catalase blocker (3-aminotriazole), but not FeEDTA and superoxide dismutase blocker (diethyldithiocarbamate), also resulted in the enhancement of regeneration efficiency. These results clearly indicate that plant regeneration is specifically regulated by endogenous H2O2 and by factors, which improve its accumulation. Moreover, a study of the activity of various SOD isoforms suggests that not only the absolute concentration of H2O2, but also its localisation might be responsible for controlling regeneration processes
Effects of vitamin E supplementation on and the association of body condition score with changes in peroxidative biomarkers and antioxidants around calving in dairy heifers
Dobbelaar, P. ; Bouwstra, R.J. ; Goselink, R.M.A. ; Jorritsma, R. ; Borne, J.J.G.C. van den; Jansen, E.H.J.M. - \ 2010
Journal of Dairy Science 93 (2010)7. - ISSN 0022-0302 - p. 3103 - 3113.
oxidative stress - periparturient period - in-vitro - superoxide-dismutase - metabolic syndrome - follicular-fluid - immune function - oxidant stress - fatty-acids - milk-yield
The objective of this study was to investigate the effect of vitamin E supplementation on oxidative status in blood, liver, milk, and ovarian follicular fluid in periparturient heifers. Vitamin E supplementation started 8 wk before calving and continued until 8 wk postpartum. Grass silage was the main forage fed during the experiment. In addition, supplemented heifers (n = 9) received 3,000 IU of vitamin E daily on a carrier food; control heifers (n = 9) consumed only the carrier food. Blood samples and liver biopsies were taken frequently throughout the study and ovarian follicular fluid was sampled at 8 wk postpartum. Body condition score was scored weekly and milk yield was measured daily. A marker of oxidative damage, determinable reactive oxygen metabolites (d-ROM), and a set of antioxidants were measured in blood, liver, milk, and ovarian follicular fluid. Control heifers had a low vitamin E status, and selenium status was marginal in control and supplemented heifers. Vitamin E supplementation increased vitamin E concentrations in blood, liver, and ovarian follicular fluid and increased triacylglycerol in liver. Serum d-ROM were not reduced by vitamin E supplementation. Superoxide dismutase and glutathione peroxidase activity in red blood cells and liver and glutathione peroxidase activity in ovarian follicular fluid were not affected by vitamin E supplementation and they were not increased around calving. Protein thiol groups and ratio of reduced glutathione to oxidized glutathione were also not increased around calving. These results suggest that heifers around calving experience a low level of oxidative processes. This might be caused by lower than expected milk production attributed to a low forage intake. Serum d-ROM were negatively correlated with protein thiol groups and positively correlated with the activity of glutathione peroxidase in red blood cells, oxidized glutathione, and the ratio of reduced glutathione and oxidized glutathione in serum. The lack of treatment effects allowed estimation of the effects of body condition 4 wk before calving and the loss of body condition on markers of lipid peroxidation and antioxidants. A trend that a body condition of =3 might result in more oxidative damage measured by serum d-ROM was observed, but fatter heifers had a significantly higher ratio of reduced glutathione to oxidized glutathione
Analysis of acid-stressed Bacillus cereus reveals a major oxidative response and inactivation-associated radical formation
Mols, J.M. ; Kranenburg, R. van; Melis, C.C.J. van; Moezelaar, R. ; Abee, T. - \ 2010
Environmental Microbiology 12 (2010)4. - ISSN 1462-2912 - p. 873 - 885.
arginine deiminase system - food poisoning toxins - nitric-oxide - listeria-monocytogenes - staphylococcus-aureus - superoxide-dismutase - tolerance response - lactococcus-lactis - genome sequence - low-ph
Acid stress resistance of the food-borne human pathogen Bacillus cereus may contribute to its survival in acidic environments, such as encountered in soil, food and the human gastrointestinal tract. The acid stress responses of B. cereus strains ATCC 14579 and ATCC 10987 were analysed in aerobically grown cultures acidified to pH values ranging from pH 5.4 to pH 4.4 with HCI. Comparative phenotype and transcriptome analyses revealed three acid stressinduced responses in this pH range: growth rate reduction, growth arrest and loss of viability. These physiological responses showed to be associated with metabolic shifts and the induction of general stress response mechanisms with a major oxidative component, including upregulation of catalases and superoxide dismutases. Flow cytometry analysis in combination with the hydroxyl (OH center dot) and peroxynitrite (ONOO-)-specific fluorescent probe 3'-(phydroxyphenyl) fluorescein (HPF) showed excessive radicals to be formed in both B. cereus strains in bactericidal conditions only. Our study shows that radicals can indicate acid-induced malfunctioning of cellular processes that lead to cell death.
Potato (Solanum tuberosum L.) tuber ageing induces changes in the proteome and antioxidants associated with the sprouting pattern
Delaplace, P. ; Fauconnier, M.L. ; Sergeant, K. ; Dierick, J.F. ; Oufir, M. ; Wal, F. van der; America, A.H.P. ; Renaut, J. ; Hausman, J.F. ; Jardin, P. du - \ 2009
Journal of Experimental Botany 60 (2009)4. - ISSN 0022-0957 - p. 1273 - 1288.
physiological age index - heat-shock proteins - lipid-peroxidation - oxidative stress - disulfide-isomerase - hydrogen-peroxide - seed-tubers - spectrophotometric method - membrane-permeability - superoxide-dismutase
During post-harvest storage, potato tubers age as they undergo an evolution of their physiological state influencing their sprouting pattern. In the present study, physiological and biochemical approaches were combined to provide new insights on potato (Solanum tuberosum L. cv. Desiree) tuber ageing. An increase in the physiological age index (PAI) value from 0.14 to 0.83 occurred during storage at 4 degrees C over 270 d. Using this reference frame, a proteomic approach was followed based on two-dimensional electrophoresis. In the experimental conditions of this study, a marked proteolysis of patatin occurred after the PAI reached a value of 0.6. In parallel, several glycolytic enzymes were up-regulated and cellular components influencing protein conformation and the response to stress were altered. The equilibrium between the 20S and 26S forms of the proteasome was modified, the 20S form that recycles oxidized proteins being up-regulated. Two proteins belonging to the cytoskeleton were also differentially expressed during ageing. As most of these changes are also observed in an oxidative stress context, an approach focused on antioxidant compounds and enzymes as well as oxidative damage on polyunsaturated fatty acids and proteins was conducted. All the changes observed during ageing seemed to allow the potato tubers to maintain their radical scavenging activity until the end of the storage period as no accumulation of oxidative damage was observed. These data are interpreted considering the impact of reactive oxygen species on the development and the behaviour of other plant systems undergoing ageing or senescence processes.
Effect of O2 concentrations on Sulfolobus solfataricus P2
Simon, G. ; Walther, J. ; Zabeti, N. ; Combet-Blanc, Y. ; Auria, R. ; Oost, J. van der; Casalot, L. - \ 2009
FEMS Microbiology Letters 299 (2009)2. - ISSN 0378-1097 - p. 255 - 260.
superoxide-dismutase - thermus-thermophilus - cytochrome ba(3) - oxidase - oxygen - archaeon - stress - identification - metabolism - enzyme
Sulfolobus solfataricus P2 was grown aerobically at various O(2) concentrations. Based on growth parameters in microcosms, four types of behavior could be distinguished. At 35% O(2) (v/v; gas phase), the cultures did not grow, indicating a lethal dose of oxygen. For 26-32% O(2), the growth was significantly affected compared with the reference (21%), suggesting a moderate toxicity by O(2). For 16-24% O(2), standard growth was observed. For 1.5-15% O(2), growth was comparable with the reference, but the yield on O(2) indicated a more efficient use of oxygen. These results indicate that S. solfataricus P2 grows optimally in the range of 1.5-24% O(2), most likely by adjusting its energy-transducing machinery. To gain some insight into control of the respiratory system, transcriptomes of the strain cultivated at different O(2) concentrations, corresponding to each behavior (1.5%, 21% and 26%), were compared using a DNA microarray approach. It showed differential expression of several genes encoding terminal oxidases, indicating an adaptation of the strain's respiratory system in response to fluctuating oxygen concentrations
Crystal structure of a family 16 endoglucanase from the hyperthermophile Pyrococcus furiosus--structural basis of substrate recognition
Ilari, A. ; Fiorillo, A. ; Angelaccio, S. ; Florio, R. ; Chiaraluce, R. ; Oost, J. van der; Consalvi, V. - \ 2009
FEBS Journal 276 (2009)4. - ISSN 1742-464X - p. 1048 - 1058.
m guanidinium chloride - ion-pair networks - glutamate-dehydrogenase - angstrom resolution - tertiary structure - electrostatic interactions - thermophilic proteins - superoxide-dismutase - thermotoga-maritima - thermal-stability
Bacterial and archaeal endo-beta-1,3-glucanases that belong to glycoside hydrolase family 16 share a beta-jelly-roll fold, but differ significantly in sequence and in substrate specificity. The crystal structure of the laminarinase (EC 22.214.171.124) from the hyperthermophilic archaeon Pyrococcus furiosus (pfLamA) has been determined at 2.1 A resolution by molecular replacement. The pfLamA structure reveals a kink of six residues (72-77) at the entrance of the catalytic cleft. This peptide is absent in the endoglucanases from alkaliphilic Nocardiopsis sp. strain F96 and Bacillus macerans, two proteins displaying an overall fold similar to that of pfLamA, but with different substrate specificity. A deletion mutant of pfLamA, lacking residues 72-75, hydrolyses the mixed-linkage beta-1,3-1,4-glucan lichenan 10 times more efficiently than the wild-type protein, indicating the importance of the kink in substrate preference
Pyruvate relieves the necessity of high induction levels of catalase and enables Campylobacter jejuni to grow under fully aerobic conditions
Verhoeff-Bakkenes, L. ; Arends, A.P. ; Snoep, J.L. ; Zwietering, M.H. ; Jonge, R. de - \ 2008
Letters in Applied Microbiology 46 (2008)3. - ISSN 0266-8254 - p. 377 - 382.
fetus subsp jejuni - superoxide-dismutase - hydrogen-peroxide - escherichia-coli - microaerophilic nature - foodborne pathogen - oxygen - metabolism - survival - aerotolerance
Aims: Several cases of campylobacteriosis reported worldwide seemingly conflict with the strict growth requirements and sensitivity to environmental stress of Campylobacter jejuni. In this study, the need for a micro-aerobic environment [dissolved oxygen tension (DOT): 0·1¿90%; 100% air saturation)] and the adaptive responses to oxygen stress were studied. Methods and Results: The growth of C. jejuni in continuous culture was assessed under different DOT in the presence or absence of pyruvate. In a medium without pyruvate, continuous cultures of C. jejuni showed typically micro-aerobic behaviour and cells were unable to grow under fully aerobic conditions. However in the presence of pyruvate (25 mmol l¿1), continuous cultures of C. jejuni were able to grow in a broad DOT range, varying from 0·1% to at least 90%, and the catalase activity was decreased. Conclusions: Addition of pyruvate results in the decrease in the concentration of hydrogen peroxide, which enables C. jejuni to grow aerobically. Significance and Impact of the Study: New information on the oxidative physiology of C. jejuni and its ability to grow aerobically in media supplemented with pyruvate is presented
Responses of two field-grown coffee species to drought and re-hydration
Cai, Z.Q. ; Chen, Y.J. ; Cao, K.F. - \ 2005
Photosynthetica 43 (2005)2. - ISSN 0300-3604 - p. 187 - 193.
increasing water-deficit - oxidative stress - photosynthetic performance - antioxidative protection - superoxide-dismutase - co2 assimilation - wheat cultivars - plants - efficiency - canephora
The gas exchange, parameters of chlorophyll fluorescence, contents of pigments, and activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), as well as lipid peroxidation were investigated in two field-grown coffee species, Coffea arabica and C. liberica, exposed to drought and re-hydration. Drought caused a more pronounced inhibition of net photosynthetic rate in C. liberica compared to C. arabica. The de-epoxidation of xanthophyll cycle pigments at midday estimated by leaf reflectance was much higher in C. arabica than in C. liberica, but no significant change was found in response to drought. Under moderate drought, the activities of SOD and APX increased significantly only in C. arabica. The maximum photochemical efficiency of photosystem 2, PS2 (Fv/Fm) at predawn did not change and there was no lipid peroxidation during this time. Under severe drought Fv/Fm decreased and initial fluorescence (F0) increased for both species, and SOD activity increased, APX activity remained relatively high, and malondialdehyde (MDA) accumulated in C. arabica, while APX decreased in C. liberica. The photosynthetic apparatus of C. arabica was completely recovered after 5 d of re-irrigation as indicated by the restoration of Fv/Fm to the control values. A lack of recovery upon rewatering of C. liberica indicated irreversible damage to PS2. Hence compared to C. liberica, C. arabica possesses a higher desiccation-induced antioxidative protection and higher portion of the total pigment pool used in photoprotection, which might aid alleviating photoinhibitory damage during desiccation and photosynthesis recovery when favourable conditions are restored
Genetic differences in seed longevity of various Arabidopsis mutants
Clerkx, E.J.M. ; Vries, M.H.C. de; Ruijs, G.J. ; Groot, S.P.C. ; Koornneef, M. - \ 2004
Physiologia Plantarum 121 (2004)3. - ISSN 0031-9317 - p. 448 - 461.
thaliana l heynh - desiccation tolerance - abscisic-acid - superoxide-dismutase - sunflower seeds - glutathione-deficient - lipid-peroxidation - oxidative damage - moisture-content - germination
Seeds gradually lose their viability during dry storage. The damage that occurs at the biochemical level can alter the seed physiological status and is affected by the storage conditions of the seeds. Although these environmental conditions controlling loss of viability have been investigated frequently, little information is available on the genetics of seed longevity. Using Arabidopsis mutants in defined developmental or biochemical pathways such as those affected in seed coat composition, seed dormancy, hormone function and control of oxidative stress, we tried to gain insight into the genes and mechanisms controlling viability of stored seeds. Mutations like abscisic acid insensitive3 (abi3) as well as abscisic acid deficient1 (aba1) show reduced longevity, which may be partially related to the seed dormancy phenotype of these mutants. Mutants with seed coat alterations, especially aberrant tests shape (ats), showed a stronger reduction in germination percentage after storage, indicating the importance of a 'functional' seed coat for seed longevity. A specific emphasis was placed on mutants affected in dealing with Reactive Oxygen Species (ROS). Because several pathways are involved in protection against ROS and because gene redundancy is a common feature in Arabidopsis, 'double' mutants were generated. These 'double' mutants and the corresponding single mutants were subjected to a controlled deterioration test (CDT) and a germination assay on hydrogen peroxide (H2O2) after prolonged storage at two relative humidities. CDT and germination on H2O2 affected all genotypes, although it appears that other effects like genetic background are more important than the deficiencies in the ROS scavenging pathway. Explanations for this limited effect of mutations affecting ROS scavenging are discussed
Internal browning in pear fruit (Pyrus communis L. cv Conference) may be a result of a limited availability of energy and antioxidants
Veltman, R.H. ; Lenthéric, I. ; Plas, L.H.W. van der; Peppelenbos, H.W. - \ 2003
Postharvest Biology and Technology 28 (2003). - ISSN 0925-5214 - p. 295 - 302.
superoxide-dismutase - atp production - ascorbic-acid - elevated co2 - apple fruit - mitochondria - respiration - catalase
Storage of pears (Pyrus communis) under hypoxia, especially in the presence of increased CO2 partial pressures, can lead to development of brown core. Disorder development, concentrations of ascorbic acid (AA) and adenosine triphosphate (ATP), and respiration were examined under various O-2 (0-21 kPa) and CO2 (0 and 5 kPa) atmospheres during 31 days of storage. ATP production was estimated using the respiration data. Hypoxia increased brown core incidence, decreased AA and ATP concentrations, and lowered ATP production. AA concentrations decreased before brown core became visible. Adding CO2 to the storage atmosphere increased the severity of brown core. CO2 addition also decreased AA levels by about 46% at O-2 partial pressures of 2.5 kPa and higher. CO2, however, had variable effects on ATP production. No brown core was found in fruit kept at 0 kPa O-2 with or without CO2, nor decreased AA levels. These results support the hypothesis that brown core initiation is a consequence of membrane damage caused by a combination of oxygen free radical action and a lack of maintenance energy. This combination may lead to decompartmentation of intracellular structures and the initiation of brown pigmentation, visible in pears with disorders. (C) 2002 Elsevier Science B.V. All rights reserved.