Cellular nucleotide measurements and applications in microbial ecology.

Karl, David M.

doi:10.1128/mmbr.44.4.739-796.1980

Cited by 340 publications

(162 citation statements)

References 142 publications

(211 reference statements)

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“…ATP was quantified with a luminometer, using the firefly bioluminescence method (Karl 1980). Absolute quantitative determinations of the amount of extracted ATP were made by measuring relative changes in peak height before and after the addition of internal standards (Holm-Hansen & Karl 1978).…”

Section: Methodsmentioning

confidence: 99%

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream¹

2005

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The processing of leaves in temperate streams has been the subject of numerous studies but equivalent tropical ecosystems have received little attention. We investigated leaf breakdown of a tropical tree species (Hura crepitans, Euphorbiaceae), in a tropical stream using leaf bags (0.5 mm mesh) over a period of 24 days. We followed the loss of mass and the changes in adenosine triphosphate (ATP) concentrations and respiration rates associated with the decomposing leaves. The breakdown rate was fast (k=−0.0672/d, kd=−0.0031/degree‐day), with 81 percent loss of the initial mass within 24 days. This high rate was probably related to the stable and high water temperature (22°C) favoring strong biological activity. Respiration rates increased until day 16 (1.1 mg O2/h/g AFDM), but maximum ATP concentrations were attained at day 9 (725 nmol ATP/g AFDM) when leaf mass remaining was 52 percent. To determine the relative importance of fungi and bacteria during leaf decomposition, ATP concentrations, and respiration rates were determined in samples treated with antibiotics, after incubation in the stream. The results of the samples treated with the antifungal or the bacterial antibiotic suggest a higher contribution of the fungal community for total microbial biomass and a higher contribution of the bacterial community for microbial respiration rates, especially during the later stages of leaf decomposition. However, these results should be analyzed with caution since both antibacterial and antifungal agents did not totally eliminate microbial activity and biomass.

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Section: Methodsmentioning

confidence: 99%

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream¹

2005

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“…The C/ATP ratio has been reviewed by Karl [1980]. The "standard" value of 250 is a mean of many observations and can not be assumed to be correct for any given environment.…”

Section: Least Squares Analysis Suggests a Dcml Value For M• Ofmentioning

confidence: 99%

“…Adenosine triphosphate (ATP) is ubiquitous in living cells and rapidly degraded outside them and so has been considered an index of total living biomass [Holm-Hansen, 1973; Karl, 1980]. To convert ATP to biomass requires a conversion factor of unknown accuracy.…”

Section: Introductionmentioning

confidence: 99%

Microbial community structure at the U.S.‐Joint Global Ocean Flux Study Station ALOHA: Inverse methods for estimating biochemical indicator ratios

Christian

Karl²

1994

J. Geophys. Res.

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Modeling biogeochemical fluxes in the marine plankton requires the application of factors for extrapolation of biomass indicators measured in the field (chlorophyll a, adenosine triphosphate, bacterial counts) to biomass carbon or nitrogen. These are often inferred from culture studies and are poorly constrained for natural populations. A least squares inverse method with a simple linear model constrains the values of several common indicator ratios, giving self‐consistent solutions that provide useful information about the structure of the microbial community at our North Pacific Ocean study site (Station ALOHA (A Long‐term Oligotrophic Habitat Assessment)). These results indicate that the fraction of the microbial biomass that is autotrophic (pigmented) is greater in the mixed layer than at the deep chlorophyll maximum layer and that heterotrophic bacteria are a significant but not necessarily predominant component of the microbial community in the euphotic zone.

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“…It is calculated from the measured concentrations of the three adenine nucleotides, ATP, ADP and AMP, which are fundamental to the energy metabolism of all organisms (Atkinson, 1977). AEC has a maximum value of 1.0 when all the adenylates are in the form of ATP and a minimum of 0.0 when they are all in the form of AMP (Karl, 1980). Values in the range 0.8e0.9 are typical of healthy and growing organisms.…”

Section: Discussionmentioning

confidence: 99%

The influence of 2‐chlorodeoxyadenosine (2‐CdA) on the adenine energy charge and glutathione content of human erythrocytes

Marczak¹,

Bukowska²,

Koczmara³

et al. 2004

Cell Biology International

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We have examined the effect of exposure of human erythrocytes to the new chemotherapy drug 2-chlorodeoxyadenosine (2-CdA, cladribine), focusing on the glutathione (GSH and GSSG) content and the adenine energy charge (AEC). Incubation of erythrocytes with 0.1-5 microg/ml 2-CdA induced no significant change in the reduced or total glutathione level or in the AMP and ATP concentrations. The ADP concentration increased slightly and the AEC value is in the range typical of healthy organisms. Incubation of erythrocytes with 2-CdA also caused cell shape changes, converting most of the cells to echinocytes.

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Cellular nucleotide measurements and applications in microbial ecology.

Abstract: Oxidation-reduction state .742 Indirect energy coupling .743 Cyclic adenosine 3',5'-monophosphate, guanosine 5'-triphosphate, and guanosine tetraphosphate .743

Cited by 340 publications

References 142 publications

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream¹

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream¹

Microbial community structure at the U.S.‐Joint Global Ocean Flux Study Station ALOHA: Inverse methods for estimating biochemical indicator ratios

The influence of 2‐chlorodeoxyadenosine (2‐CdA) on the adenine energy charge and glutathione content of human erythrocytes

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Cellular nucleotide measurements and applications in microbial ecology.

Abstract: Oxidation-reduction state .742 Indirect energy coupling .743 Cyclic adenosine 3',5'-monophosphate, guanosine 5'-triphosphate, and guanosine tetraphosphate .743

Cited by 340 publications

References 142 publications

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream1

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream1

Microbial community structure at the U.S.‐Joint Global Ocean Flux Study Station ALOHA: Inverse methods for estimating biochemical indicator ratios

The influence of 2‐chlorodeoxyadenosine (2‐CdA) on the adenine energy charge and glutathione content of human erythrocytes

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Product

Resources

About

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream¹

Microbial Biomass, Respiration, and Decomposition of Hura crepitans L. (Euphorbiaceae) Leaves in a Tropical Stream¹