Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake
ABSTRACT The effect of irradiance in the range of 400 to 700 nm or photosynthetically active radiation (PAR) on bacterial heterotrophic production estimated by the incorporation of 3 H-leucine (referred to herein as Leu) was investigated in the northwestern Mediterranean Sea and in a coastal North A...
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American Society for Microbiology
2001
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Online Access: | http://dx.doi.org/10.1128/aem.67.9.3795-3801.2001 https://journals.asm.org/doi/pdf/10.1128/AEM.67.9.3795-3801.2001 |
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crasmicro:10.1128/aem.67.9.3795-3801.2001 2023-11-05T03:43:52+01:00 Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake Morán, Xosé Anxelu G. Massana, Ramon Gasol, Josep M. 2001 http://dx.doi.org/10.1128/aem.67.9.3795-3801.2001 https://journals.asm.org/doi/pdf/10.1128/AEM.67.9.3795-3801.2001 en eng American Society for Microbiology https://journals.asm.org/non-commercial-tdm-license Applied and Environmental Microbiology volume 67, issue 9, page 3795-3801 ISSN 0099-2240 1098-5336 Ecology Applied Microbiology and Biotechnology Food Science Biotechnology journal-article 2001 crasmicro https://doi.org/10.1128/aem.67.9.3795-3801.2001 2023-10-09T15:51:46Z ABSTRACT The effect of irradiance in the range of 400 to 700 nm or photosynthetically active radiation (PAR) on bacterial heterotrophic production estimated by the incorporation of 3 H-leucine (referred to herein as Leu) was investigated in the northwestern Mediterranean Sea and in a coastal North Atlantic site, with Leu uptake rates ranging over 3 orders of magnitude. We performed in situ incubations under natural irradiance levels of Mediterranean samples taken from five depths around solar noon and compared them to incubations in the dark. In two of the three stations large differences were found between light and dark uptake rates for the surfacemost samples, with dark values being on average 133 and 109% higher than in situ ones. Data obtained in coastal North Atlantic waters confirmed that dark enclosure may increase Leu uptake rates more than threefold. To explain these differences, on-board experiments of Leu uptake versus irradiance were performed with Mediterranean samples from depths of 5 and 40 m. Incubations under a gradient of 12 to 1,731 μmol of photons m −2 s −1 evidenced a significant increase in incorporation rates with increasing PAR in most of the experiments, with dark-incubated samples departing from this pattern. These results were not attributed to inhibition of Leu uptake in the light but to enhanced bacterial response when transferred to dark conditions. The ratio of dark to light uptake rates increased as dissolved inorganic nitrogen concentrations decreased, suggesting that bacterial nutrient deficiency was overcome by some process occurring only in the dark bottles. Article in Journal/Newspaper North Atlantic ASM Journals (American Society for Microbiology - via Crossref) Applied and Environmental Microbiology 67 9 3795 3801 |
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Open Polar |
collection |
ASM Journals (American Society for Microbiology - via Crossref) |
op_collection_id |
crasmicro |
language |
English |
topic |
Ecology Applied Microbiology and Biotechnology Food Science Biotechnology |
spellingShingle |
Ecology Applied Microbiology and Biotechnology Food Science Biotechnology Morán, Xosé Anxelu G. Massana, Ramon Gasol, Josep M. Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake |
topic_facet |
Ecology Applied Microbiology and Biotechnology Food Science Biotechnology |
description |
ABSTRACT The effect of irradiance in the range of 400 to 700 nm or photosynthetically active radiation (PAR) on bacterial heterotrophic production estimated by the incorporation of 3 H-leucine (referred to herein as Leu) was investigated in the northwestern Mediterranean Sea and in a coastal North Atlantic site, with Leu uptake rates ranging over 3 orders of magnitude. We performed in situ incubations under natural irradiance levels of Mediterranean samples taken from five depths around solar noon and compared them to incubations in the dark. In two of the three stations large differences were found between light and dark uptake rates for the surfacemost samples, with dark values being on average 133 and 109% higher than in situ ones. Data obtained in coastal North Atlantic waters confirmed that dark enclosure may increase Leu uptake rates more than threefold. To explain these differences, on-board experiments of Leu uptake versus irradiance were performed with Mediterranean samples from depths of 5 and 40 m. Incubations under a gradient of 12 to 1,731 μmol of photons m −2 s −1 evidenced a significant increase in incorporation rates with increasing PAR in most of the experiments, with dark-incubated samples departing from this pattern. These results were not attributed to inhibition of Leu uptake in the light but to enhanced bacterial response when transferred to dark conditions. The ratio of dark to light uptake rates increased as dissolved inorganic nitrogen concentrations decreased, suggesting that bacterial nutrient deficiency was overcome by some process occurring only in the dark bottles. |
format |
Article in Journal/Newspaper |
author |
Morán, Xosé Anxelu G. Massana, Ramon Gasol, Josep M. |
author_facet |
Morán, Xosé Anxelu G. Massana, Ramon Gasol, Josep M. |
author_sort |
Morán, Xosé Anxelu G. |
title |
Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake |
title_short |
Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake |
title_full |
Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake |
title_fullStr |
Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake |
title_full_unstemmed |
Light Conditions Affect the Measurement of Oceanic Bacterial Production via Leucine Uptake |
title_sort |
light conditions affect the measurement of oceanic bacterial production via leucine uptake |
publisher |
American Society for Microbiology |
publishDate |
2001 |
url |
http://dx.doi.org/10.1128/aem.67.9.3795-3801.2001 https://journals.asm.org/doi/pdf/10.1128/AEM.67.9.3795-3801.2001 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Applied and Environmental Microbiology volume 67, issue 9, page 3795-3801 ISSN 0099-2240 1098-5336 |
op_rights |
https://journals.asm.org/non-commercial-tdm-license |
op_doi |
https://doi.org/10.1128/aem.67.9.3795-3801.2001 |
container_title |
Applied and Environmental Microbiology |
container_volume |
67 |
container_issue |
9 |
container_start_page |
3795 |
op_container_end_page |
3801 |
_version_ |
1781702704672800768 |