scholarly journals Elemental Composition (C, N, P) and Cell Volume of Exponentially Growing and Nutrient-Limited Bacterioplankton

2002 ◽  
Vol 68 (6) ◽  
pp. 2965-2971 ◽  
Author(s):  
Katarina Vrede ◽  
Mikal Heldal ◽  
Svein Norland ◽  
Gunnar Bratbak
Keyword(s):  
Elemental Composition ◽  
Standard Error ◽  
Stationary Phases ◽  
Growth Conditions ◽  
Elemental Content ◽  
Bacterial Cells ◽  
Batch Cultures ◽  
C Cell ◽  
Average Standard Error ◽  
C:P Ratios

ABSTRACT Marine bacterioplankton were isolated and grown in batch cultures until their growth became limited by organic carbon (C), nitrogen (N), or phosphorus (P). Samples were taken from the cultures at both the exponential and stationary phases. The elemental composition of individual bacterial cells was analyzed by X-ray microanalysis with an electron microscope. The cell size was also measured. The elemental content was highest in exponentially growing cells (149 ± 8 fg of C cell−1, 35 ± 2 fg of N cell−1, and 12 ± 1 fg of P cell−1; average of all isolates ± standard error). The lowest C content was found in C-limited cells (39 ± 3 fg of C cell−1), the lowest N content in C- and P-limited cells (12 ± 1 and 12 ± 2 fg of N cell−1, respectively), and the lowest P content in P-limited cells (2.3 ± 0.6 fg of P cell−1). The atomic C:N ratios varied among treatments between 3.8 ± 0.1 and 9.5 ± 1.0 (average ± standard error), the C:P ratios between 35 ± 2 and 178 ± 28, and the N:P ratios between 6.7 ± 0.3 and 18 ± 3. The carbon-volume ratios showed large variation among isolates due to different types of nutrient limitation (from 51± 4 to 241 ± 38 fg of C μm−1; average of individual isolates and treatments ± standard error). The results show that different growth conditions and differences in the bacterial community may explain some of the variability of previously reported elemental and carbon-volume ratios.

scholarly journals Divergent Adaptation Strategies of Vascular Facultative Epiphytes to Bark and Soil Habitats: Insights from Stoichiometry

Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 16
Author(s):  
Tingting Zhang ◽  
Wenyao Liu ◽  
Tao Hu ◽  
Dandan Tang ◽  
Yuxuan Mo ◽  
...  
Keyword(s):  
Elemental Composition ◽  
Forest Ecosystems ◽  
Adaptation Strategies ◽  
P Elements ◽  
Nutritional Conditions ◽  
Variable Element ◽  
C:P Ratios ◽  
Strong Control ◽  
Forest Habitats ◽  
Cultivation Experiment

Understanding the stoichiometric traits of plants is critical for studying their ecological adaptation strategies. Facultative epiphytes (which can also live on the ground) are an important component of epiphytic flora of montane forest ecosystems. However, a key gap persists in our understanding how facultative epiphytes can adapt different nutritional conditions of ground and canopy habitats? To study adaptive strategies of facultative epiphytes and the characteristics of the content and stoichiometric homeostasis of C, N, and P elements, we conducted a field experiment and a greenhouse N and P additions cultivation experiment. We found that epiphytic individuals of facultative epiphytes showed lower C:N and C:P ratios, higher variation in elemental composition, and more pronounced N limitation than terrestrial individuals. Moreover, facultative epiphytes showed strong control over the elemental composition of leaves, and their stoichiometric homeostasis of leaves and stems were stronger than roots. Furthermore, the homeostasis of facultative epiphytes decreased in the order N > P. Our results indicated that epiphytic and terrestrial individuals of facultative epiphytes have difference in nutrient limitation, and they use plastic strategies in different habitats. Epiphytic individuals survive in the intermittent habitat through luxury consumption of nutrient while terrestrial individuals were relatively conservative nutrient users. Furthermore, our results implied that facultative epiphytes maintain stable metabolic leaf activity via variable element concentrations of roots to adapt to highly heterogeneous forest habitats.

scholarly journals Revealing the Metabolic Alterations during Biofilm Development of Burkholderia cenocepacia Based on Genome-Scale Metabolic Modeling

Metabolites ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 221
Author(s):  
Ozlem Altay ◽  
Cheng Zhang ◽  
Hasan Turkez ◽  
Jens Nielsen ◽  
Mathias Uhlén ◽  
...  
Keyword(s):  
Systems Biology ◽  
Alternative Pathway ◽  
Growth Conditions ◽  
Pentose Phosphate ◽  
Burkholderia Cenocepacia ◽  
Bacterial Cells ◽  
Metabolic Remodeling ◽  
Transcriptomics Data ◽  
Biofilm Development ◽  
Genome Scale

Burkholderia cenocepacia is among the important pathogens isolated from cystic fibrosis (CF) patients. It has attracted considerable attention because of its capacity to evade host immune defenses during chronic infection. Advances in systems biology methodologies have led to the emergence of methods that integrate experimental transcriptomics data and genome-scale metabolic models (GEMs). Here, we integrated transcriptomics data of bacterial cells grown on exponential and biofilm conditions into a manually curated GEM of B. cenocepacia. We observed substantial differences in pathway response to different growth conditions and alternative pathway susceptibility to extracellular nutrient availability. For instance, we found that blockage of the reactions was vital through the lipid biosynthesis pathways in the exponential phase and the absence of microenvironmental lysine and tryptophan are essential for survival. During biofilm development, bacteria mostly had conserved lipid metabolism but altered pathway activities associated with several amino acids and pentose phosphate pathways. Furthermore, conversion of serine to pyruvate and 2,5-dioxopentanoate synthesis are also identified as potential targets for metabolic remodeling during biofilm development. Altogether, our integrative systems biology analysis revealed the interactions between the bacteria and its microenvironment and enabled the discovery of antimicrobial targets for biofilm-related diseases.

Haemolytic activity in different species of the genus Prymnesium (Haptophyta)

2016 ◽  
Vol 97 (3) ◽  
pp. 491-496 ◽  
Author(s):  
S. Seoane ◽  
P. Riobó ◽  
J. Franco
Keyword(s):  
Stationary Phases ◽  
Growth Conditions ◽  
Economic Losses ◽  
Haemolytic Activity ◽  
Brackish Waters ◽  
Extraction Solvent ◽  
Fatty Acid Amides ◽  
The World ◽  
Allelopathic Effects ◽  
Different Strains

The genus Prymnesium includes several species that produce toxins with cytotoxic, ichthyotoxic, neurotoxic and haemolytic activity. Bloom episodes of Prymnesium species have been reported from several parts of the world (North America, Europe, Africa, Asia and Australia), especially from temperate and subtropical regions and most of them from brackish waters. Blooms cause great economic losses to aquaculture and fisheries around the world. The ichthyotoxic and allelopathic effects of Prymnesium have been linked to the presence of Haemolysin 1, Prymnesins 1 and 2 and, more recently, fatty acids and fatty acid amides. The toxicology of this genus with regard to different growth conditions such as light, nutrients and other parameters has been well documented. It is unknown, however, whether different species and strains from the Prymnesium genus all produce the same types and level of toxins. In this study, we have determined the haemolytic activity of eight different strains from the genus Prymnesium in both exponential and stationary phases of growth. We have also evaluated the efficiency of the extraction solvent.

scholarly journals Variability in Elemental Composition of Conifer Tree Rings

2021 ◽  
pp. 24-37
Author(s):  
Vladimir L. Gavrikov ◽  
◽  
Alexey I. Fertikov ◽  
Evgenii A. Vaganov ◽  
Keyword(s):  
Elemental Composition ◽  
Tree Rings ◽  
Chemical Elements ◽  
Dimensional Space ◽  
Siberian Larch ◽  
Growth Conditions ◽  
Pinus Sibirica ◽  
Siberian Spruce ◽  
Long Term Experiment ◽  
Conifer Tree

Distribution of chemical elements in tree rings bears important information on various biogeochemical processes. In order to achieve a reliable interpretation of the information, it is necessary to know the degree of variation in the content of chemical elements both at the level of the entire species and at the level of individual trees. The research aims to determine which chemical elements have a stable distribution in the trunks of a number of conifers: Siberian spruce (Picea obovata Ledeb.), Scots pine (Pinus sylvestris L.), Siberian larch (Larix sibirica Ledeb.), and Siberian pine (Pinus sibirica Du Tour). The data for the analysis were obtained on the basis of the long-term experiment in forest growing. The experimental site was laid out in 1971–1972 in the vicinity of Krasnoyarsk by the staff of the Sukachev Institute of Forest of the Siberian Branch of the Russian Academy of Sciences. Before planting the seedlings, the soil ground was mechanically levelled, and thus, sufficiently equal growth conditions were created for all plantings. Cores with a diameter of 12 mm were sampled from three normally developing trees of each species and analyzed using modern X-ray fluorescence methods. Content relative values of elements (counts) were obtained with the Itrax Multiscanner (COX Analytical Systems). The content of elements in the tree rings was characterized by the concentration and reserve of elements. Concentration was calculated as the number of counts per 1 mm2 of the ring area; reserve was calculated as the number of counts over the entire ring area. Each of these variables was defined by the parameters of linear slope in the calendar year series and the standard deviation. The cluster analysis was performed in the 4-dimensional space of the obtained parameters. This allowed determining whether the series of element distributions from different trees and species are grouped. Three elements (Ca, Co, and P) show high stability of distribution parameters in tree rings with no regard to tree species. A number of other elements (Mn, Pb, Cl, Cr, Ni, Sr, and W) are stably grouped depending on the species. The results of the research enable to focus on the study of the elements stably distributed in the conifer trunks. For citation: Gavrikov V.L., Fertikov A.I., Sharafutdinov R.A., Vaganov E.A. Variability in Elemental Composition of Conifer Tree Rings. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 24–37. DOI: 10.37482/0536-1036-2021-6-24-37

The elemental composition of bacteria: A signature of growth conditions?

1996 ◽  
Vol 33 (1-6) ◽  
pp. 3-9 ◽  
Author(s):  
Mikal Heldal ◽  
Svein Norland ◽  
Kjell Magne Fagerbakke ◽  
Frede Thingstad ◽  
Gunnar Bratbak
Keyword(s):  
Elemental Composition ◽  
Growth Conditions

The impact of species, respiration type, growth phase and genetic inventory on absolute metal content of intact bacterial cells

Metallomics ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 925-935 ◽  
Author(s):  
Rohit Budhraja ◽  
Chang Ding ◽  
Philipp Walter ◽  
Stephan Wagner ◽  
Thorsten Reemtsma ◽  
...  
Keyword(s):  
Growth Phase ◽  
Metal Ion ◽  
Metal Content ◽  
Growth Conditions ◽  
Bacterial Cells ◽  
Ion Content ◽  
Whole Cells ◽  
Microbial Species ◽  
The Impact

Absolute metal ion content was determined from whole cells of different microbial species and changes were related to growth conditions and change of encoded genes.

Parameters for growth measurement in suspension cultures of plant cells

1974 ◽  
Vol 52 (4) ◽  
pp. 903-912 ◽  
Author(s):  
Dyson Rose ◽  
S. M. Martin
Keyword(s):  
Stationary Phases ◽  
Plant Cells ◽  
Growth Period ◽  
Dry Weight ◽  
High Rate ◽  
Growth Phases ◽  
Batch Cultures ◽  
Growth Measurement ◽  
Large Increments ◽  
Uptake And Metabolism

Well-adapted cells, which had been initiated from root tissue of Ipomoea and of Daucus carota, were grown in 7.5-liter stirred-jar fermenters, and both the cells and media were analyzed for major components at intervals during the growth period. Controlled variables included the size of inoculum, the amount of sucrose, and the source and amount of nitrogen in the media.The data obtained indicate that there are two distinct growth phases in the development of batch cultures of these cell lines. The first, which we term "cytoplasmic growth phase," begins immediately upon addition of inoculum to fresh medium and is characterized by a high rate of nitrogen uptake and metabolism relative to the increase in cell dry weight. The second, or "maturation phase," is characterized by large increments in dry weight and total cell carbohydrate relative to the increments in cell nitrogen. It is suggested that the classical lag, log, and stationary phases of bacterial growth could apply only to the early hours of cytoplasmic growth, if indeed they are relevant at all.

ALTERNATIVE PROGENY TESTING PROGRAMS FOR WEANING WEIGHT AND EASE OF CALVING IN BEEF CATTLE

1980 ◽  
Vol 60 (3) ◽  
pp. 609-620 ◽  
Author(s):  
G. F. S. HUDSON ◽  
L. R. SCHAEFFER ◽  
J. W. WILTON
Keyword(s):  
Beef Cattle ◽  
Standard Error ◽  
Design Patterns ◽  
Mixed Model ◽  
Herd Size ◽  
Progeny Testing ◽  
Weaning Weight ◽  
Calving Ease ◽  
Model Equations ◽  
Average Standard Error

Progeny test programs were characterized by numbers of young bulls, successful matings (conceptions) per young bull, herds in which each young sire was used, proven bulls used as reference sires and herd size. Matings to reference sires were calculated as a percentage of the number of young sire matings. Designs were simulated and mixed-model equations formed and added to equations obtained from the Canadian ROP program for years 1971–1978. The average standard error of prediction (SEP) of young bulls was used for comparing designs. Increasing matings per young sire decreased SEP curvilinearly. The curvilinearity was greater when either herd size or herds per young sire was low. Increasing herd size and herds per young sire improved connectedness between sires and reduced SEP. Number of young sires affected SEP only when fewer than 10 bulls were sampled. Number of young sire matings were more important in reducing SEP than percent reference sire matings. If number of young sire matings was adequate to achieve a desired level of SEP, 10% reference sire matings were sufficient. The number of reference sires used did not affect SEP. Design patterns affected SEP of weaning weight (h2 = 0.25) and calving ease (h2 = 0.10) similarly. SEP was not affected by the number of proven sires in a breed (Maine Anjou, 133 sires or Blonde d’Aquitaine, 39 sires) or by the connectedness between proven sires.

scholarly journals Superoxide dismutase, catalase, and peroxidase in ammonium-grown and nitrogen-fixing Azospirillum brasilense

1984 ◽  
Vol 30 (10) ◽  
pp. 1222-1228 ◽  
Author(s):  
Richard W. Clara ◽  
Roger Knowles
Keyword(s):  
Superoxide Dismutase ◽  
Electron Acceptor ◽  
Azospirillum Brasilense ◽  
Polyacrylamide Gel Electrophoresis ◽  
Growth Conditions ◽  
Sod Activity ◽  
Batch Cultures ◽  
Physiological Conditions ◽  
Azospirillum Brasilense Sp7 ◽  
In Cells

Superoxide dismutase (SOD), catalase (CAT), and peroxidase (PER) activities were studied in ammonium-grown and N2-fixing batch cultures of Azospirillum brasilense Sp7. PER activity, as measured using o-dianisidine or 3,3′-diaminobenzidine as the H donor, was not significant in most growth conditions. SOD activity increased in response to higher O2 concentrations but was also present in cells grown anaerobically with nitrate [Formula: see text] or nitrous oxide (N2O) as electron acceptor. CAT activity increased at lower O2 concentrations and was highest in cells grown anaerobically with [Formula: see text] as electron acceptor. Polyacrylamide gel electrophoresis of cell-free extracts revealed only one band of SOD activity under each of the physiological conditions employed, compared with three for aerobically grown Escherichia coli K12. This band proved to be iron-containing SOD (FeSOD) on the basis of inhibitor sensitivity.

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