Superoxide Dismutase as a Protective Enzyme Against Oxygen Toxicity: An Overview and Initial Studies in Trichodesmium

Cunningham, Kathryn A.; Capone, Douglas G.

doi:10.1007/978-94-015-7977-3_22

Cited by 6 publications

(7 citation statements)

References 41 publications

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“…In addition, initial work on superoxide dismutase activity indicates that this enzyme is present in Trichodesmium spp. and may participate in nitrogenase protection by removing oxygen radicals (4). We believe that several mechanisms may be operating together to protect nitrogenase from oxygen deactivation.…”

Section: Spheres Pm-2)mentioning

confidence: 93%

Cytochrome Oxidase: Subcellular Distribution and Relationship to Nitrogenase Expression in the Nonheterocystous Marine Cyanobacterium Trichodesmium thiebautii

Bergman

Siddiqui

Carpenter

et al. 1993

Appl Environ Microbiol

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Immunochemical labeling was used to study the subcellular distribution of cytochrome oxidase, a respiratory protein, in Trichodesmium thiebautii. The protein was found associated with both cytoplasmic and thylakoid membranes. About a sixfold variation in the protein content (gold particle count) was found among Trichodesmium cells within a single colony. Double labeling was performed with cytochrome oxidase and nitrogenase antisera. Regression analysis of gold particle counts per unit of cell area of cytochrome oxidase and nitrogenase showed a positive correlation (r2 = 0.911); cells with higher nitrogenase levels also had higher levels of cytochrome oxidase. The parallel expression of two proteins suggests that respiratory oxygen uptake may be involved in nitrogenase protection (respiratory protection) in Trichodesmium spp.

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Section: Spheres Pm-2)mentioning

confidence: 93%

Cytochrome Oxidase: Subcellular Distribution and Relationship to Nitrogenase Expression in the Nonheterocystous Marine Cyanobacterium Trichodesmium thiebautii

Bergman

Siddiqui

Carpenter

et al. 1993

Appl Environ Microbiol

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“…Environmental stress can trigger ROS production, which disturbs the steady-state balance of prooxidants and antioxidants (Okamoto and Colepicolo, 1998). The toxicity of oxygen radicals to biological systems has been well documented (Fridovich, 1978;Cunningham and Capone, 1992). At the cellular level, the damaging effects of ROS include denaturation of enzymes, depolymerization of polysaccharides, DNA damage that results in genetic mutation (Cunningham and Capone, 1992), and severe cellular injury or death (Okamoto and Colepicolo, 1998).…”

Section: R Reactive Oxygen Speciesmentioning

confidence: 99%

“…The toxicity of oxygen radicals to biological systems has been well documented (Fridovich, 1978;Cunningham and Capone, 1992). At the cellular level, the damaging effects of ROS include denaturation of enzymes, depolymerization of polysaccharides, DNA damage that results in genetic mutation (Cunningham and Capone, 1992), and severe cellular injury or death (Okamoto and Colepicolo, 1998). Lipid molecules are susceptible to oxygen-radical-induced peroxidation via the removal of hydrogen radicals, and such damage can lead to destruction of membrane integrity (Cunningham and Capone, 1992).…”

Section: R Reactive Oxygen Speciesmentioning

confidence: 99%

“…At the cellular level, the damaging effects of ROS include denaturation of enzymes, depolymerization of polysaccharides, DNA damage that results in genetic mutation (Cunningham and Capone, 1992), and severe cellular injury or death (Okamoto and Colepicolo, 1998). Lipid molecules are susceptible to oxygen-radical-induced peroxidation via the removal of hydrogen radicals, and such damage can lead to destruction of membrane integrity (Cunningham and Capone, 1992). The production of ROS by microalgae appears to principally affect fish (Tanaka et al, 1992;Yang et al, 1995;Ishimatsu et al, 1996aIshimatsu et al, , 1996b, although other organisms may also be affected (Tables 10 and 11).…”

Section: R Reactive Oxygen Speciesmentioning

confidence: 99%

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The Effects of Harmful Algal Blooms on Aquatic Organisms

Landsberg

2002

Reviews in Fisheries Science

1,126

807

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“…This phenomenon has also been observed by Kana (1992) who attributed the high 0, consumption to the Mehler reaction (production of 02-by photosystem I followed by the conversion of 02-into H202 by a superoxide dismutase) and to a high basal respiration rate. Cunningham & Capone (1992) have reported the presence of a Fe superoxide dismutase in Trichodesmium, and Bergman et al (1993) observed a strong correlation between the expression of nitrogenase and an aa3-type cytochrome oxidase in Trichodesmium thiebautii cells. The lag period measured for N2 fixation after the disruption of colonies grown in culture suggests that these biochemical processes are not always present at a level sufficient to protect nitrogenase activity from oxygen evolution in our Tnchodesmium cultures.…”

Section: Systems I and I1 In The Colonial Trichomes Thismentioning

confidence: 99%

Trichodesmium spp. physiology and nutrient fluxes in the North Pacific subtropical gyre

Letelier¹,

Karl²

1998

Aquat. Microb. Ecol.

128

100

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The potential role of the diazotrophic cyanobactenum Trichodesn~ium spp. in nitrogen and phosphorus dynamics of the euphotic zone of the North Pacific subtropical gyre was investigated as one component of the Hawaii Ocean Time-series (HOT) program. Experiments were conducted with natural samples collected at Stn ALOHA (22" 45' N, 158" W) and with isolated cultures in laboratory. In both sets of experiments, we documented aerobic nitrogenase activity in Trichodesmium by acetylene (C2H2) reduction to ethylene (C2H4). Although average C2H4 evolution per unit chlorophyll a (chl a) was lower in naturally occurring single trichomes relative to colonies 13.9 vs 12.5 nmol C2H, (pg chl a)-' h-', respectively], the generally greater blomass of single trichomes in the North Pacific Ocean suggests that trichomes may be important in the oceanic N cycle. Disrupted colonies display the lowest nitrogenase activities, but these activities increase with time in cultures. These observations and the relatively high dark oxygen consumption rates observed for Trichodesmium [0.18 pm01 O2 (pg chl a)-' h-'] suggest that, in nature, this cyanobacterium may be able to protect nitrogenase from oxygen inactivation, and that colony formation enhances, but is not prerequisite for, nitrogenase activity. Trichodesmium spp. collected from different depth strata at Stn ALOHA were also used to study variations in the C:N:P elemental composition of rising and sinking colonies. Although changes in elemental ratios were small. the relative C:N increase in all sinking colonies and the N:P decrease in rising colonies, sampled at approximately 100 m depth, is consistent wlth the model of Tr~chodesmium storage of carbohydrate in shallow waters (<20 m) and uptake of P at depth. The active uptake of inorganic phosphorus measured in sinking colonies incubated in the dark combined with a change toward positive buoyancy in colonies during the incubation supports the hypothesis that vertical migrations of Trichodesmium may represent an upward transport of P into the euphotic zone and a potential decoupling of N and P nutrient cycles. However, these results do not explain the large concentration of non-migratory single trichomes observed in the upper water column of Stn ALOHA, unless colony versus free trichome morphology is a transient condition that is under cellular control.

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Superoxide Dismutase as a Protective Enzyme Against Oxygen Toxicity: An Overview and Initial Studies in Trichodesmium

Cited by 6 publications

References 41 publications

Cytochrome Oxidase: Subcellular Distribution and Relationship to Nitrogenase Expression in the Nonheterocystous Marine Cyanobacterium Trichodesmium thiebautii

Cytochrome Oxidase: Subcellular Distribution and Relationship to Nitrogenase Expression in the Nonheterocystous Marine Cyanobacterium Trichodesmium thiebautii

The Effects of Harmful Algal Blooms on Aquatic Organisms

Trichodesmium spp. physiology and nutrient fluxes in the North Pacific subtropical gyre

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