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Corina P. D. Brussaard - One of the best experts on this subject based on the ideXlab platform.
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Fatty acid dynamics during viral infection of Phaeocystis globosa
Aquatic Microbial Ecology, 2015Co-Authors: Nicole J. Bale, Corina P. D. Brussaard, Douwe S. Maat, Ellen C. Hopmans, Anchelique Mets, J.s. Sinninghe Damsté, S. SchoutenAbstract:Previous studies have shown that viral infection can affect the lipid distribution of phytoplankton, specifically the fatty acid (FA) distribution, and has been hypothesized to affect the nutritional value of phytoplankton for higher trophic levels. Here, we report the bulk FA distribution as well as the FA distribution of individual intact polar lipid (IPL) classes of the alga Phaeocystis globosa infected with the lytic virus PgV-07T. Analysis of the virus PgV-07T itself showed that it contained shorter, more saturated bulk and IPL-bound FAs than the host. Viral infection did not affect the bulk or IPL-bound FA distribution after 24 h post-infection when cell lysis was initiated, but after 48 h the bulk FAs remaining in the particulate phase of the infected cultures contained 22% less polyunsaturated FAs (PUFAs) compared to the control cultures. This change in the bulk FAs was mainly due to the generation of PUFAs that occurred in the control cultures, suggesting that infection prevented P. globosa PUFA accumulation. Two of the 7 IPL classes, the monogalactosyldiacylglycerols and the sulfoquinovosyldiacylglycerols, showed about a 10% reduction in the percentage of PUFAs upon viral infection. In contrast, the digalactosyldiacylglycerols exhibited a 15% increase in PUFAs. This difference between the IPL-PUFAs and the bulk FAs is possibly due to a contribution to the bulk FA pool of e.g. triacylglycerols. Overall, these results suggest that grazing on infected cells and filter feeder uptake of post-lysis cell debris could lead to a transfer of relatively lower amounts of PUFAs to higher trophic levels.
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Acquisition of intact polar lipids from the prymnesiophyte Phaeocystis globosa by its lytic virus PgV-07T
Biogeosciences, 2014Co-Authors: D. S. Maat, Anne-claire Baudoux, S. Schouten, N. J. Bale, E. C. Hopmans, J. S. Sinninghe Damsté, Corina P. D. BrussaardAbstract:Recent studies showed changes in phytoplankton lipid composition during viral infection and have indicated roles for specific lipids in the mechanisms of algal virus-host interaction. To investigate the generality of these findings and obtain a better understanding of the allocation of specific lipids to viruses, we studied the intact polar lipid (IPL) composition of virally infected and non-nfected cultures of the prymnesiophyte Phaeocystis globosa G(A) and its lytic virus PgV-07T. The P. globosa IPL composition was relatively stable over a diel cycle and not strongly affected by viral infection. Glycolipids, phospholipids and betaine lipids were present in both the host and virus, although specific groups such as the diacylglyceryl-hydroxymethyltrimethyl-beta-alanines and the sulfoquinovo-syldiacylglycerols, were present in a lower proportion or were not detected in the virus. Viral glycosphingolipids (vGSLs), which have been shown to play a role in the infection strategy of the virus EhV-86, infecting the prymnesiophyte Emiliania huxleyi CCMP374, were not encountered. Our results show that the involvement of lipids in virus-algal host interactions can be very different amongst virus-algal host systems.
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responses of the coastal bacterial community to viral infection of the algae Phaeocystis globosa
The ISME Journal, 2014Co-Authors: Abdul Sheik, Corina P. D. Brussaard, Gaute Lavik, Phyllis Lam, Niculina Musat, Andreas Krupke, Sten Littmann, Marc Strous, Marcel M M KuypersAbstract:The release of organic material upon algal cell lyses has a key role in structuring bacterial communities and affects the cycling of biolimiting elements in the marine environment. Here we show that already before cell lysis the leakage or excretion of organic matter by infected yet intact algal cells shaped North Sea bacterial community composition and enhanced bacterial substrate assimilation. Infected algal cultures of Phaeocystis globosa grown in coastal North Sea water contained gamma-and alphaproteobacterial phylotypes that were distinct from those in the non-infected control cultures 5 h after infection. The gammaproteobacterial population at this time mainly consisted of Alteromonas sp. cells that were attached to the infected but still intact host cells. Nano-scale secondary-ion mass spectrometry (nanoSIMS) showed similar to 20% transfer of organic matter derived from the infected C-13- and N-15-labelled P. globosa cells to Alteromonas sp. cells. Subsequent, viral lysis of P. globosa resulted in the formation of aggregates that were densely colonised by bacteria. Aggregate dissolution was observed after 2 days, which we attribute to bacteriophage-induced lysis of the attached bacteria. Isotope mass spectrometry analysis showed that 40% of the particulate C-13-organic carbon from the infected P. globosa culture was remineralized to dissolved inorganic carbon after 7 days. These findings reveal a novel role of viruses in the leakage or excretion of algal biomass upon infection, which provides an additional ecological niche for specific bacterial populations and potentially redirects carbon availability.
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Characterization of different viruses infecting the marine harmful algal bloom species Phaeocystis globosa.
Virology, 2005Co-Authors: Anne-claire Baudoux, Corina P. D. BrussaardAbstract:Abstract Twelve lytic viruses (PgV) infecting the marine unicellular eukaryotic harmful algal bloom species Phaeocystis globosa were isolated from the southern North Sea in 2000–2001 and partially characterized. All PgV isolates shared common phenotypic features with other algal viruses belonging to the family Phycodnaviridae and could be categorized in four different groups. Two main groups (PgV Group I and II) were discriminated based on particle size (150 and 100 nm respectively), genome size (466 and 177 kb) and structural protein composition. The lytic cycle showed a latent period of 10 h for PgV Group I and latent periods of 12 h and 16 h for PgV Group IIA and IIB. Host specificity and temperature sensitivity finally defined a fourth group (PgV Group IIC). Our results imply that viral infection plays an important role not only in P. globosa dynamics but also in the diversity of both host and virus community.
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Isolation and phylogenetic analysis of novel viruses infecting the phytoplankton Phaeocystis globosa (Prymnesiophyceae)
Applied and Environmental Microbiology, 2004Co-Authors: Corina P. D. Brussaard, C. M. Frederickson, Steven M Short, Curtis A. SuttleAbstract:Viruses infecting the harmful bloom-causing alga Phaeocystis globosa (Prymnesiophyceae) were readily isolated from Dutch coastal waters (southern North Sea) in 2000 and 2001. Our data show a large increase in the abundance of putative P. globosa viruses during blooms of P. globosa, suggesting that viruses are an important source of mortality for this alga. In order to examine genetic relatedness among viruses infecting P. globosa and other phytoplankton, DNA polymerase gene (pol) fragments were amplified and the inferred amino acid sequences were phylogenetically analyzed. The results demonstrated that viruses infecting P. globosa formed a closely related monophyletic group within the family Phycodnaviridae, with at least 96.9% similarity to each other. The sequences grouped most closely with others from viruses that infect the prymnesiophyte algae Chrysochromulina brevifilum and Chrysochromulina strobilus. Whether the P. globosa viruses belong to the genus Prymnesiovirus or form a separate group needs further study. Our data suggest that, like their phytoplankton hosts, the Chrysochromulina and Phaeocystis viruses share a common ancestor and that these prymnesioviruses and their algal host have coevolved.
Xihua Cao - One of the best experts on this subject based on the ideXlab platform.
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the mechanism of a new type of modified clay controlling Phaeocystis globosa growth
Journal of Oceanology and Limnology, 2020Co-Authors: Lixia Qiu, Xihua Cao, Xiuxian SongAbstract:Phaeocystis globosa is a harmful algal bloom (HAB) species worldwide. Using modified clay (MC) to control HABs and to mitigate their adverse effects is currently a commonly used method in China. In this paper, the effects of oxidized composite modified clay (OXI-MC) on P. globosa were studied from different perspectives. The results show that the OXI-MC could effectively remove P. globosa and inhibit both the growth of residual algal cells and the formation of new colonies. The P. globosa algal biomass removal efficiencies after 3 h reached 90% at a dose of 0.1 g/L, and the number of colonies with different particle sizes was greatly reduced. Compared with those of the control, the superoxide dismutase (SOD) activity, catalase (CAT) activity, and malondialdehyde (MDA) content of the residual algae significantly increased, indicating that OXI-MC caused oxidative stress in the algal cells. In addition, we evaluated the effects of OXI-MC on the photosynthesis of residual microalgae and found that the maximal photochemical efficiency of photosystem II (PSII) under dark adaptation (Fv/Fm) and actual photochemical efficiency of PSII (ΦPSII) decreased, severely damaging the photosynthesis efficiency, implying that OXI-MC effected the photosynthesis system of P. globosa. The results of this study clarify that OXI-MC could remove the most of algal cells and break up the colonies of P. globosa by collision, flocculation, and releasing active substances, as well as inhibit effectively the growth and colony formation of residual P. globosa by causing oxidative stress, reducing photosynthesis activity, accelerating the degradation of polysaccharides, and inhibiting the formation of colonies.
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nutritional strategy for the preferential uptake of text no _ 3 text n by Phaeocystis globosa
Hydrobiologia, 2019Co-Authors: Xiuxian Song, Yongquan Yuan, Xihua CaoAbstract:The cosmopolitan alga Phaeocystis globosa forms massive colonies during blooms. In addition to producing haemolytic toxins that affect the ecosystem, centimetre-sized colonies can block nuclear power plant cooling systems. Nitrogen plays a key role in P. globosa blooms; however, the preferred form of inorganic nitrogen taken up by colonies remains unknown. Therefore, we set up four groups with different nitrogen types and levels of enrichment. The culture medium and intracolonial fluid were sampled at different times for the determination of nutrient concentrations to elucidate the nutrient uptake strategy that presumably favours colonies. Although \({{\text{NH}}_{4}}^{ + } {\text{ {-} N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) were absorbed by the colonies, \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was the favoured nitrogen, and the average uptake rate of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was significantly higher than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) in each group (P < 0.05). In the enriched groups, the replenishment of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) in the intracolonial fluid was faster than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\). The symbiotic bacteria and some biochemical processes may explain the differences in the nutrient concentrations inside and outside of the colonies. Considering the high consumption of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) during P. globosa blooms, controlling the concentration of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) is key to preventing P. globosa blooms.
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Nutritional strategy for the preferential uptake of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) by Phaeocystis globosa
Hydrobiologia, 2019Co-Authors: Xiuxian Song, Yongquan Yuan, Xihua CaoAbstract:The cosmopolitan alga Phaeocystis globosa forms massive colonies during blooms. In addition to producing haemolytic toxins that affect the ecosystem, centimetre-sized colonies can block nuclear power plant cooling systems. Nitrogen plays a key role in P. globosa blooms; however, the preferred form of inorganic nitrogen taken up by colonies remains unknown. Therefore, we set up four groups with different nitrogen types and levels of enrichment. The culture medium and intracolonial fluid were sampled at different times for the determination of nutrient concentrations to elucidate the nutrient uptake strategy that presumably favours colonies. Although \({{\text{NH}}_{4}}^{ + } {\text{ {-} N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) were absorbed by the colonies, \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was the favoured nitrogen, and the average uptake rate of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was significantly higher than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) in each group (P < 0.05). In the enriched groups, the replenishment of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) in the intracolonial fluid was faster than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\). The symbiotic bacteria and some biochemical processes may explain the differences in the nutrient concentrations inside and outside of the colonies. Considering the high consumption of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) during P. globosa blooms, controlling the concentration of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) is key to preventing P. globosa blooms.
Laurent Seuront - One of the best experts on this subject based on the ideXlab platform.
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mesoscale and microscale spatial variability of bacteria and viruses during a Phaeocystis globosa bloom in the eastern english channel
Estuarine Coastal and Shelf Science, 2008Co-Authors: Mark J. Doubell, Justin R. Seymour, Laurent Seuront, James G. MitchellAbstract:Sampling was conducted within inshore and offshore sites, characterized by highly dissimilar hydrodynamic and hydrobiological conditions, in the Eastern English Channel. The eutrophic inshore site was dominated by the influence of a dense bloom of the Prymnesiophyceae phytoplankton species Phaeocystis globosa, while the offshore site was characterized by more oceanic conditions. Within each site the microscale distributions of chlorophyll a and several flow cytometrically-defined subpopulations of heterotrophic bacteria and viruses were measured at a spatial resolution of 5 cm. The inshore site was characterized by comparatively high levels of microscale spatial variability, with concentrations of chlorophyll a, heterotrophic bacteria, and viruses varying by 8, 11 and 3.5-fold respectively across distances of several centimeters. Within the offshore site, microscale distributions of chlorophyll a and bacteria were markedly less variable than within the inshore site, although viruses exhibited slightly higher levels of heterogeneity. Significant mesoscale variability was also observed when mean microbial parameters were compared between the inshore and offshore sites. However, when the extent of change (max/min and coefficient of variation) was compared between meso- and microscales, the variability observed at the microscale, particularly in the inshore site, was substantially greater. This pattern suggests that microscale processes associated with Phaeocystis globosa bloom dynamics can generate heterogeneity amongst microbial communities to a greater degree than large scale oceanographic discontinuities.
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increased seawater viscosity Phaeocystis globosa spring bloom and temora longicornis feeding and swimming behaviours
Marine Ecology Progress Series, 2008Co-Authors: Laurent Seuront, Dorothee VincentAbstract:The suggested influence of increased seawater viscosity on the feeding and swimming behaviours of adult females of the calanoid copepod Temora longicornis was investigated during a Phaeocystis globosa spring bloom in the coastal waters of the eastern English Channel. Adult female gut contents did not exhibit any significant correlation with chlorophyll concentration or seawater excess viscosity over the course of the bloom. Instead, the highest gut contents were observed when the seawater viscosity was maximum (up to 4.6 centipoise (cP)), after a 5-fold decrease in chlorophyll concentration related to the formation of foam. This demonstrates that even high viscosity did not mechanically hamper zooplankton grazing. Gut contents were controlled by the taxonomic availabil- ity rather than the quantitative availability of phytoplankton-based food. This is consistent with the observed sustained egg production rates despite drastic changes in the composition of protist resource over the course of the bloom. Before and after the bloom (in the absence of P. globosa), T. longicornis exhibited similar swimming paths characterized by their large spatial extent and low curviness. In contrast, during the bloom their movements were spatially more localised, significantly slower and more convoluted. This behaviour is suggested as an adaptive strategy to optimise forag- ing activity during P. globosa blooms, which have been recently shown to generate high level of phytoplankton patchiness.
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The influence of Phaeocystis globosa on microscale spatial patterns of chlorophyll a and bulk-phase seawater viscosity
Biogeochemistry, 2007Co-Authors: Laurent Seuront, C. Lacheze, Mark J. Doubell, V. Van Dongen-vogels, Kelly Newton, Justin R. Seymour, Anne-carlijn Alderkamp, James G. MitchellAbstract:A two-dimensional microscale (5 cm resolution) sampler was used over the course of a phytoplankton spring bloom dominated by Phaeocystis globosa to investigate the structural properties of chlorophyll a and seawater excess viscosity distributions. The microscale distribution patterns of chlorophyll a and excess viscosity were never uniform nor random. Instead they exhibited different types and levels of aggregated spatial patterns that were related to the dynamics of the bloom. The chlorophyll a and seawater viscosity correlation patterns were also controlled by the dynamics of the bloom with positive and negative correlations before and after the formation of foam in the turbulent surf zone. The ecological relevance and implications of the observed patchiness and biologically induced increase in seawater viscosity are discussed and the combination of the enlarged colonial form and mucus secretion is suggested as a competitive advantage of P. globosa in highly turbulent environments where this species flourishes.
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Effects of small-scale turbulence on Phaeocystis globosa (Prymnesiophyceae) growth and life cycle
Journal of Experimental Marine Biology and Ecology, 2006Co-Authors: Mathilde Nelly Schapira, Laurent Seuront, Valérie GentilhommeAbstract:Abstract The response of Phaeocystis globosa to small-scale turbulence was studied in 5 l microcosms. Turbulence was generated by oscillating grids. The effect of small-scale turbulence was examined under 3 turbulence levels representative of the P. globosa natural environment, and in non-turbulent control cultures. Single cell numbers, nitrogen concentrations and colony formation (number and diameter) were followed over 13 days in each experimental culture. Small-scale turbulence decreased single cell growth and also influenced colony formation. More colonies were formed when turbulence increased to a given threshold, but above this turbulence level, fewer and smaller colonies were observed in P. globosa cultures. The ecological significance of these results, particularly, the potential influence of small-scale turbulence on competition mechanisms between P. globosa and diatoms are finally discussed and suggested as a key factor to understand phytoplankton successions in the Eastern English Channel.
James G. Mitchell - One of the best experts on this subject based on the ideXlab platform.
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mesoscale and microscale spatial variability of bacteria and viruses during a Phaeocystis globosa bloom in the eastern english channel
Estuarine Coastal and Shelf Science, 2008Co-Authors: Mark J. Doubell, Justin R. Seymour, Laurent Seuront, James G. MitchellAbstract:Sampling was conducted within inshore and offshore sites, characterized by highly dissimilar hydrodynamic and hydrobiological conditions, in the Eastern English Channel. The eutrophic inshore site was dominated by the influence of a dense bloom of the Prymnesiophyceae phytoplankton species Phaeocystis globosa, while the offshore site was characterized by more oceanic conditions. Within each site the microscale distributions of chlorophyll a and several flow cytometrically-defined subpopulations of heterotrophic bacteria and viruses were measured at a spatial resolution of 5 cm. The inshore site was characterized by comparatively high levels of microscale spatial variability, with concentrations of chlorophyll a, heterotrophic bacteria, and viruses varying by 8, 11 and 3.5-fold respectively across distances of several centimeters. Within the offshore site, microscale distributions of chlorophyll a and bacteria were markedly less variable than within the inshore site, although viruses exhibited slightly higher levels of heterogeneity. Significant mesoscale variability was also observed when mean microbial parameters were compared between the inshore and offshore sites. However, when the extent of change (max/min and coefficient of variation) was compared between meso- and microscales, the variability observed at the microscale, particularly in the inshore site, was substantially greater. This pattern suggests that microscale processes associated with Phaeocystis globosa bloom dynamics can generate heterogeneity amongst microbial communities to a greater degree than large scale oceanographic discontinuities.
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The influence of Phaeocystis globosa on microscale spatial patterns of chlorophyll a and bulk-phase seawater viscosity
Biogeochemistry, 2007Co-Authors: Laurent Seuront, C. Lacheze, Mark J. Doubell, V. Van Dongen-vogels, Kelly Newton, Justin R. Seymour, Anne-carlijn Alderkamp, James G. MitchellAbstract:A two-dimensional microscale (5 cm resolution) sampler was used over the course of a phytoplankton spring bloom dominated by Phaeocystis globosa to investigate the structural properties of chlorophyll a and seawater excess viscosity distributions. The microscale distribution patterns of chlorophyll a and excess viscosity were never uniform nor random. Instead they exhibited different types and levels of aggregated spatial patterns that were related to the dynamics of the bloom. The chlorophyll a and seawater viscosity correlation patterns were also controlled by the dynamics of the bloom with positive and negative correlations before and after the formation of foam in the turbulent surf zone. The ecological relevance and implications of the observed patchiness and biologically induced increase in seawater viscosity are discussed and the combination of the enlarged colonial form and mucus secretion is suggested as a competitive advantage of P. globosa in highly turbulent environments where this species flourishes.
Xiuxian Song - One of the best experts on this subject based on the ideXlab platform.
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the mechanism of a new type of modified clay controlling Phaeocystis globosa growth
Journal of Oceanology and Limnology, 2020Co-Authors: Lixia Qiu, Xihua Cao, Xiuxian SongAbstract:Phaeocystis globosa is a harmful algal bloom (HAB) species worldwide. Using modified clay (MC) to control HABs and to mitigate their adverse effects is currently a commonly used method in China. In this paper, the effects of oxidized composite modified clay (OXI-MC) on P. globosa were studied from different perspectives. The results show that the OXI-MC could effectively remove P. globosa and inhibit both the growth of residual algal cells and the formation of new colonies. The P. globosa algal biomass removal efficiencies after 3 h reached 90% at a dose of 0.1 g/L, and the number of colonies with different particle sizes was greatly reduced. Compared with those of the control, the superoxide dismutase (SOD) activity, catalase (CAT) activity, and malondialdehyde (MDA) content of the residual algae significantly increased, indicating that OXI-MC caused oxidative stress in the algal cells. In addition, we evaluated the effects of OXI-MC on the photosynthesis of residual microalgae and found that the maximal photochemical efficiency of photosystem II (PSII) under dark adaptation (Fv/Fm) and actual photochemical efficiency of PSII (ΦPSII) decreased, severely damaging the photosynthesis efficiency, implying that OXI-MC effected the photosynthesis system of P. globosa. The results of this study clarify that OXI-MC could remove the most of algal cells and break up the colonies of P. globosa by collision, flocculation, and releasing active substances, as well as inhibit effectively the growth and colony formation of residual P. globosa by causing oxidative stress, reducing photosynthesis activity, accelerating the degradation of polysaccharides, and inhibiting the formation of colonies.
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nutritional strategy for the preferential uptake of text no _ 3 text n by Phaeocystis globosa
Hydrobiologia, 2019Co-Authors: Xiuxian Song, Yongquan Yuan, Xihua CaoAbstract:The cosmopolitan alga Phaeocystis globosa forms massive colonies during blooms. In addition to producing haemolytic toxins that affect the ecosystem, centimetre-sized colonies can block nuclear power plant cooling systems. Nitrogen plays a key role in P. globosa blooms; however, the preferred form of inorganic nitrogen taken up by colonies remains unknown. Therefore, we set up four groups with different nitrogen types and levels of enrichment. The culture medium and intracolonial fluid were sampled at different times for the determination of nutrient concentrations to elucidate the nutrient uptake strategy that presumably favours colonies. Although \({{\text{NH}}_{4}}^{ + } {\text{ {-} N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) were absorbed by the colonies, \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was the favoured nitrogen, and the average uptake rate of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was significantly higher than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) in each group (P < 0.05). In the enriched groups, the replenishment of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) in the intracolonial fluid was faster than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\). The symbiotic bacteria and some biochemical processes may explain the differences in the nutrient concentrations inside and outside of the colonies. Considering the high consumption of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) during P. globosa blooms, controlling the concentration of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) is key to preventing P. globosa blooms.
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Nutritional strategy for the preferential uptake of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) by Phaeocystis globosa
Hydrobiologia, 2019Co-Authors: Xiuxian Song, Yongquan Yuan, Xihua CaoAbstract:The cosmopolitan alga Phaeocystis globosa forms massive colonies during blooms. In addition to producing haemolytic toxins that affect the ecosystem, centimetre-sized colonies can block nuclear power plant cooling systems. Nitrogen plays a key role in P. globosa blooms; however, the preferred form of inorganic nitrogen taken up by colonies remains unknown. Therefore, we set up four groups with different nitrogen types and levels of enrichment. The culture medium and intracolonial fluid were sampled at different times for the determination of nutrient concentrations to elucidate the nutrient uptake strategy that presumably favours colonies. Although \({{\text{NH}}_{4}}^{ + } {\text{ {-} N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) were absorbed by the colonies, \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was the favoured nitrogen, and the average uptake rate of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) was significantly higher than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\) and \({{\text{NO}}_{2}}^{ - } {\text{{-}N}}\) in each group (P < 0.05). In the enriched groups, the replenishment of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) in the intracolonial fluid was faster than that of \({{\text{NH}}_{4}}^{ + } {\text{{-}N}}\). The symbiotic bacteria and some biochemical processes may explain the differences in the nutrient concentrations inside and outside of the colonies. Considering the high consumption of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) during P. globosa blooms, controlling the concentration of \({{\text{NO}}_{3}}^{ - } {\text{{-}N}}\) is key to preventing P. globosa blooms.