Aquatic Microbial Ecology最新文献_第8页

P-limitation drives changes in DOM production by aquatic bacteria p限制驱动水生细菌产生DOM的变化

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-08-06 DOI: 10.3354/ame01940

Seth K. Thompson, J. Cotner

{"title":"P-limitation drives changes in DOM production by aquatic bacteria","authors":"Seth K. Thompson, J. Cotner","doi":"10.3354/ame01940","DOIUrl":"https://doi.org/10.3354/ame01940","url":null,"abstract":"Heterotrophic bacteria are key biogeochemical regulators in freshwater systems. Through both decomposition and production of organic matter, bacteria link multiple biogeochemical cycles together. While there has been a significant amount of work done on understanding the role of microbes in the aquatic carbon cycle, important linkages with other biogeochemical cycles will require more information about how organic matter transformations impact other nutrients, such as phosphorus. In this study, we conducted a culture-based laboratory experiment to examine the production of dissolved organic matter (DOM) by heterotrophic bacteria under varied nutrient conditions. In addition to quantifying the production of dissolved organic carbon (DOC), we also measured the production of dissolved organic phosphorus (DOP) and characterized the microbially produced organic matter using optical properties. Results demonstrated that measurable amounts of DOC and DOP were produced by heterotrophic bacteria under nutrient regimes ranging from carbon-limitation to strong phosphorus-limitation. Additionally, optical characterization of DOM revealed that the organic matter produced by bacteria grown under high phosphorus conditions was highly aromatic with similar optical properties to terrestrially derived organic matter. Overall, these findings suggest that heterotrophic bacteria can be important producers of organic matter in freshwaters and that continued trends of increased nutrient concentrations (eutrophication) may fundamentally change the composition of microbially produced organic matter in freshwater systems.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"36 1","pages":"35-46"},"PeriodicalIF":1.4,"publicationDate":"2020-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74497755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Influence of increased nutrient supply on Microcystis aeruginosa at cellular and proteomic levels 增加营养供给对铜绿微囊藻细胞和蛋白质组学水平的影响

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-08-06 DOI: 10.3354/ame01939

Yunhan Jiang, Ying Liu

{"title":"Influence of increased nutrient supply on Microcystis aeruginosa at cellular and proteomic levels","authors":"Yunhan Jiang, Ying Liu","doi":"10.3354/ame01939","DOIUrl":"https://doi.org/10.3354/ame01939","url":null,"abstract":"Various studies have observed that increased nutrient supply promotes the growth of bloom-forming cyanobacteria, but only a limited number of studies have investigated the influence of increased nutrient supply on bloom-forming cyanobacteria at the proteomic level. We investigated the cellular and proteomic responses of Microcystis aeruginosa to elevated nitrogen and phosphorus supply. Increased supply of both nutrients significantly promoted the growth of M. aeruginosa and the synthesis of chlorophyll a, protein, and microcystins. The release of microcystins and the synthesis of polysaccharides negatively correlated with the growth of M. aeruginosa under high nutrient levels. Overexpressed proteins related to photosynthesis, and amino acid synthesis, were responsible for the stimulatory effects of increased nutrient supply in M. aeruginosa. Increased nitrogen supply directly promoted cyanobacterial growth by inducing the overexpression of the cell division regulatory protein FtsZ. NtcA, that regulates gene transcription related to both nitrogen assimilation and microcystin synthesis, was overexpressed under the high nitrogen condition, which consequently induced overexpression of 2 microcystin synthetases (McyC and McyF) and promoted microcystin synthesis. Elevated nitrogen supply induced the overexpression of proteins involved in gas vesicle organization (GvpC and GvpW), which may increase the buoyancy of M. aeruginosa. Increased phosphorus level indirectly affected growth and the synthesis of cellular substances in M. aeruginosa through the mediation of differentially expressed proteins related to carbon and phosphorus metabolism. This study provides a comprehensive description of changes in the proteome of M. aeruginosa in response to an increased supply of 2 key nutrients.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"66 1","pages":"47-58"},"PeriodicalIF":1.4,"publicationDate":"2020-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80628528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Distinct processes structure bacterioplankton and protist communities across an oceanic front 不同的过程结构浮游细菌和原生生物群落跨越海洋前沿

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-08-06 DOI: 10.3354/ame01938

Ro Allen, T. Summerfield, K. Currie, P. Dillingham, L. Hoffmann

{"title":"Distinct processes structure bacterioplankton and protist communities across an oceanic front","authors":"Ro Allen, T. Summerfield, K. Currie, P. Dillingham, L. Hoffmann","doi":"10.3354/ame01938","DOIUrl":"https://doi.org/10.3354/ame01938","url":null,"abstract":"Bacterioplankton and protists fulfil key roles in marine ecosystems. Understanding the abundance and distribution of these organisms through space and time is a central focus of biological oceanographers. The role of oceanographic features, in addition to environmental conditions, in structuring bacterioplankton and protist communities has been increasingly recognised. We investigated patterns in bacterioplankton and protist diversity and community structure across the Southland Front system, a compaction of the subtropical front zone, to the east of New Zealand’s South Island. We collected 24 seawater samples across a ~65 km transect and characterised bacterioplankton and protist community composition using high-throughput sequencing of the 16S and 18S rRNA genes, respectively. We identified frontal waters as a bacterioplankton diversity hotspot relative to neighbouring subtropical and subantarctic waters, but did not find evidence of this effect in protists. Bacterioplankton showed pronounced spatial structuring across the front, with communities closely tracking water type through the region. Protist communities also tracked water type through the region, though this effect was substantially less pronounced. We used an ecological null model approach to demonstrate that protist communities are primarily assembled through stochastic processes, whilst bacterioplankton are primarily assembled through deterministic processes across the Southland Front system. We suggest that this divergence emerges from fundamental differences in the characteristics of bacterioplankton and protist communities. Our findings add to a growing body of literature highlighting the importance of oceanographic features in shaping bacterioplankton and protist communities, promoting the necessity for such features to be considered more explicitly in the future.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"35 1","pages":"19-34"},"PeriodicalIF":1.4,"publicationDate":"2020-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90460986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Nutrient availability and organic matter quality shape bacterial community structure in a lake biofilm 营养物有效性和有机质质量决定了湖泊生物膜中的细菌群落结构

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-07-16 DOI: 10.3354/ame01937

RC Seballos, Kevin H. Wyatt, RJ Bernot, S. Brown, S. Chandra, A. Rober

{"title":"Nutrient availability and organic matter quality shape bacterial community structure in a lake biofilm","authors":"RC Seballos, Kevin H. Wyatt, RJ Bernot, S. Brown, S. Chandra, A. Rober","doi":"10.3354/ame01937","DOIUrl":"https://doi.org/10.3354/ame01937","url":null,"abstract":"Heterotrophic bacteria play a key role in ecosystem processes, but little is known about the factors that shape bacterial community structure in aquatic biofilms, especially in lakes. We used molecular techniques (16S rRNA) to evaluate resource controls on biofilm bacterial community structure in an oligotrophic subalpine lake. We manipulated nutrients (nitrogen and phosphorus; NP) and glucose (G) on inorganic (rock) and organic (wood) substrates under light and dark conditions (i.e. with and without autotrophy, respectively) in a full factorial design using nutrient diffusing substrates in situ for 20 d. Distinct patterns of separation in community structure between treatments with nutrients (NP, NP+G) and without nutrients (control, G-only) indicated that community structure was more strongly influenced by nutrients than organic matter irrespective of substrate type or light availability. Further separation in community structure between treatments with nutrients only (NP) and nutrients with glucose (NP+G) on both organic and inorganic substrates indicated that once nutrient limitation was alleviated, organic matter quality played an important role in shaping community structure. Differences in the relative abundance of 6 phyla, 3 classes, and 19 genera among treatments revealed (1) contrasting taxa-specific resource requirements, (2) the influence of interspecific interactions on composition, and (3) the potential for individual taxa to participate in the decomposition of recalcitrant organic matter. Our findings provide insight into the role that nutrients and organic matter quality play in shaping bacterial community structure, which is a critical step in bridging the knowledge gap between microbial composition and ecosystem function within aquatic environments.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"8 1","pages":"1-18"},"PeriodicalIF":1.4,"publicationDate":"2020-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87792238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Spatial-temporal dynamics of N-cycle functional genes in a temperate Atlantic estuary (Douro, Portugal) 温带大西洋河口n -循环功能基因的时空动态(Douro，葡萄牙)

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-07-02 DOI: 10.3354/ame01935

P. Salgado, A. Machado, A. Bordalo

{"title":"Spatial-temporal dynamics of N-cycle functional genes in a temperate Atlantic estuary (Douro, Portugal)","authors":"P. Salgado, A. Machado, A. Bordalo","doi":"10.3354/ame01935","DOIUrl":"https://doi.org/10.3354/ame01935","url":null,"abstract":"Understanding the spatial and seasonal dynamics of nitrogen (N)-cycle microbial communities is pivotal for the knowledge of N biogeochemistry. The present study addressed the spatial−temporal variability of nitrification (bacterial and archaeal amoA) and denitrification (nirS, nirK, and nosZI) key genes, as well as of non-denitrifying nitrous oxide (N2O) reducers (nosZII), coupled with key environmental variables, in an estuarine ecosystem (Douro, NW Portugal). Samples were collected on a monthly basis over 1 yr, key physical-chemical parameters were measured, and specific functional gene abundances were assayed. The results revealed a clear seasonality for nirS, nosZII, and bacterial and archaeal amoA abundance, with an increase during the winter/spring seasons. This period was especially characterized by high levels of dissolved oxygen, low temperature, low salinity, and increased turbidity. Indeed, turbidity emerged as the key factor controlling the distribution of nirS, nosZII bacterial, and archaeal amoA abundance. In contrast, the abundance of nosZI increased during the summer, while nirK abundance was enhanced from the fall to late spring. Additionally, the availability of dissolved inorganic nitrogen nutrients had no commensurable effect on N-cycle functional genes. This study of the annual variation of Ncycle functional genes in a temperate Atlantic estuary provides a major contribution to the understanding of how environmental factors potentially influence the distribution and abundance of Ncycle microbial communities.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"509 13","pages":"205-216"},"PeriodicalIF":1.4,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72432719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Ciliate diversity in cold water spring sources in Iceland 冰岛冷泉源的纤毛虫多样性

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-06-18 DOI: 10.3354/ame01936

Ragnhildur Guðmundsdóttir, Agnes-Katharina Kreiling, B. Kristjánsson, V. T. Marteinsson, S. Pálsson

{"title":"Ciliate diversity in cold water spring sources in Iceland","authors":"Ragnhildur Guðmundsdóttir, Agnes-Katharina Kreiling, B. Kristjánsson, V. T. Marteinsson, S. Pálsson","doi":"10.3354/ame01936","DOIUrl":"https://doi.org/10.3354/ame01936","url":null,"abstract":"Cold groundwater springs at the edges of lava fields along the volcanic active zone in Iceland are an interesting habitat, presenting an ecotone between groundwater, surface water and the terrestrial ecosystems. They are categorized as fennoscandian mineral-rich springs according to the European Nature Information System (EUNIS) classification (C2.111 European Environmental Agency) and have a high conservation value. They are also an island-like phenomena in the landscape and, together with the stable chemical and physical properties of the groundwater, make excellent study sites for testing questions regarding community assembly theory. To explore the biota of these systems, we applied environmental metabarcoding to assess ciliate diversity in this habitat. DNA was extracted and metabarcoding based on the 18S rRNA gene was conducted for (1) water samples and (2) glass beads as support for biomass development. Alpha diversity for ciliate communities in the spring sources increased with temperature, and limnocrene springs had fewer, more abundant taxa than rheocrene springs. Differences were observed between the water samples and the glass bead samples, mainly in terms of abundance. When considering only the water samples, no variation was found among spring source communities, indicating that stochastic processes such as dispersal and ecological drift might be important in shaping the community composition.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"1 1","pages":"191-203"},"PeriodicalIF":1.4,"publicationDate":"2020-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86295462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Composition and distribution patterns of eukaryotic microbial plankton in the ultra-oligotrophic Eastern Mediterranean Sea 超少营养东地中海真核微生物浮游生物的组成和分布模式

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-06-04 DOI: 10.3354/ame01933

Ioulia Santi, P. Kasapidis, S. Psarra, G. Assimakopoulou, A. Pavlidou, M. Protopapa, A. Tsiola, C. Zeri, P. Pitta

{"title":"Composition and distribution patterns of eukaryotic microbial plankton in the ultra-oligotrophic Eastern Mediterranean Sea","authors":"Ioulia Santi, P. Kasapidis, S. Psarra, G. Assimakopoulou, A. Pavlidou, M. Protopapa, A. Tsiola, C. Zeri, P. Pitta","doi":"10.3354/ame01933","DOIUrl":"https://doi.org/10.3354/ame01933","url":null,"abstract":"Marine microbial eukaryotes play crucial roles in water-column ecosystems; however, there are regional gaps in the investigation of natural microbial eukaryote communities, and uncertainties concerning their distribution persevere. This study combined 18S rRNA metabarcoding, biomass measurements and statistical analyses of multiple environmental variables to examine the distribution of planktonic microbial eukaryotes at different sites and water layers in the ultra-oligotrophic Eastern Mediterranean Sea (Western Levantine Basin). Our results showed that microbial eukaryotic communities were structured by depth. In surface waters, different sites shared high percentages of molecular operational taxonomic units (MOTUs), but this was not the case for deep-sea communities (≥1000 m). Plankton biomass was significantly different among sites, implying that communities of a similar composition may not support the same activity or population size. The deep-sea communities showed high percentages of unassigned MOTUs, highlighting the sparsity of the existing information on deep-sea plankton eukaryotes. Water temperature and dissolved organic matter significantly affected community distribution. Micro-eukaryotic distribution was additionally affected by the nitrogen to phosphorus ratio and viral abundance, while nano- and pico-communities were affected by zooplankton. The present study explores microbial plankton eukaryotes in their natural oligotrophic environment and highlights that, even within restricted oceanic areas, marine plankton may follow distribution patterns that are largely controlled by environmental variables.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"50 1","pages":"155-173"},"PeriodicalIF":1.4,"publicationDate":"2020-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75617778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Viral infection of prokaryotic plankton during early formation of the North Atlantic Deep Water 北大西洋深水形成初期原核浮游生物的病毒感染

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-06-04 DOI: 10.3354/ame01934

M. Weinbauer, C. Griebler, H. V. Aken, G. Herndl

{"title":"Viral infection of prokaryotic plankton during early formation of the North Atlantic Deep Water","authors":"M. Weinbauer, C. Griebler, H. V. Aken, G. Herndl","doi":"10.3354/ame01934","DOIUrl":"https://doi.org/10.3354/ame01934","url":null,"abstract":"Viral abundance was assessed in different water masses of the NW Atlantic, and the development of viral abundance, lytic viral infection and lysogeny was followed for the first ca. 5000 km (corresponding to ca. 50 yr in the oceanic conveyor belt) of the western branch of the North Atlantic Deep Water (NADW). Viral abundance was significantly higher in the 100 m layer than in the NADW (2400-2700 m depth) and the Denmark Strait Overflow Water (2400-3600 m depth). The virus-to-prokaryote ratio (VPR) increased with depth, ranging from 32-43 for different water masses of the bathypelagic ocean, thus corroborating the enigma of high viral abundance in the dark ocean. The O2-minimum layer (250-600 m) also showed high viral abundance and VPRs. Viral abundance, a viral subgroup and VPRs decreased in a non-linear form with distance from the NADW origin. Viral production (range: 0.2-2.4 × 107 viruses l-1) and the fraction of lytically infected cells (range: 1-22%) decreased with increasing distance from the formation site of the NADW. Conservative estimations of virus-mediated mortality of prokaryotes in the NADW averaged 20 ± 12%. The fraction of the prokaryotic community with lysogens (i.e. harboring a functional viral DNA) in the NADW averaged 21 ± 14%. Hence, we conclude that (1) viral abundance and subgroups differ between water masses, (2) virus-mediated mortality of prokaryotes as well as lysogeny are significant in the dark ocean and (3) the lysogenic life strategy became more important than the lytic life style during the early formation of the NADW.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"16 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2020-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79106266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Impact of euxinic holomictic conditions on prokaryotic assemblages in a marine meromictic lake 海洋分生湖泊缺氧完整环境对原核生物组合的影响

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-05-14 DOI: 10.3354/ame01931

M. Čanković, Jurica Zucko, I. Petrić, M. Marguš, I. Ciglenečki

{"title":"Impact of euxinic holomictic conditions on prokaryotic assemblages in a marine meromictic lake","authors":"M. Čanković, Jurica Zucko, I. Petrić, M. Marguš, I. Ciglenečki","doi":"10.3354/ame01931","DOIUrl":"https://doi.org/10.3354/ame01931","url":null,"abstract":"The water column of marine Rogoznica Lake (Croatia) is stratified throughout the year. However, on rare occasions, the lake exhibits complete mixing, primarily driven by meteorological conditions. On such occasions, anoxic, sulfide-rich bottom water mixes with the oxic surface layer, triggering both the oxidation of sulfide predominantly to colloidal sulfur and the establishment of euxinic conditions throughout the water column. We investigated prokaryotic communities during euxinic holomictic conditions. High-throughput sequencing of the 16S rRNA gene showed that these sulfur-driven communities were dominated by Planctomycetales, chemolithotrophic Epsilonbactereota (mainly Arcobacteraceae) and Gammaproteobacteria (Thioglobaceae), followed by Alpha- (Rhodobacteraceae) and Deltaproteobacteria (Desulfobulbaceae and Desulfobacteraceae). The majority of archaeal sequences belonged to Nanoarchaeota, all of which were designated as Woesearchaeia. This class has not been recorded in other meromictic lakes. Both bacterial and archaeal 16S rRNA gene abundance did not vary significantly across the vertical profile of the lake, as shown by quantitative PCR. However, hierarchical clustering showed a significant difference between the microbial assemblage structure in stratified periods and during a holomictic event. Besides the structure, this stressful event had a manifold effect on bacterial and archaeal assemblages by decreasing their diversity and abundance when compared to the usual stratified conditions.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"169 1","pages":"141-154"},"PeriodicalIF":1.4,"publicationDate":"2020-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83022510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Quantification of small-scale heterogeneity in aquatic aminopeptidase activity 水生氨基肽酶活性的小尺度异质性定量分析

IF 1.4 4区环境科学与生态学

Aquatic Microbial Ecology Pub Date : 2020-04-30 DOI: 10.3354/ame01930

B. Gaas, J. Ammerman

{"title":"Quantification of small-scale heterogeneity in aquatic aminopeptidase activity","authors":"B. Gaas, J. Ammerman","doi":"10.3354/ame01930","DOIUrl":"https://doi.org/10.3354/ame01930","url":null,"abstract":"Leucine aminopeptidase (LAP) is one of the enzymes involved in the hydrolysis of peptides, and is sometimes used to indicate potential nitrogen limitation in microbes. Small-scale variability has the potential to confound interpretation of underlying patterns in LAP activity in time or space. An automated flow-injection analysis instrument was used to address the small-scale variability of LAP activity within contiguous regions of the Hudson River plume (New Jersey, USA). LAP activity had a coefficient of variation (CV) of ca. 0.5 with occasional values above 1.0. The mean CVs for other biological parameters—chlorophyll fluorescence and nitrate concentration—were similar, and were much lower for salinity. LAP activity changed by an average of 35 nmol l-1 h-1 at different salinities, and variations in LAP activity were higher crossing region boundaries than within a region. Differences in LAP activity were ±100 nmol l-1 h-1 between sequential samples spaced <10 m apart. Variogram analysis indicated an inherent spatial variability of 52 nmol l-1 h-1 throughout the study area. Large changes in LAP activity were often associated with small changes in salinity and chlorophyll fluorescence, and were sensitive to the sampling frequency. This study concludes that LAP measurements in a sample could realistically be expected to range from zero to twice the average, and changes between areas or times should be at least 2-fold to have some degree of confidence that apparent patterns (or lack thereof) in activity are real.","PeriodicalId":8112,"journal":{"name":"Aquatic Microbial Ecology","volume":"34 1","pages":"127-140"},"PeriodicalIF":1.4,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82111261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0