Kinetics of nitrogen- or phosphorus-limited growth and effects of growth conditions on nutrient uptake inChattonella antiqua

ABSTRACTThe kinetics of the formation of Cu3Si in Cu/a-Si diffusion couples have been investigated by means of differential scanning calorimetry and x-ray diffraction. Multilayered composites of average stoichiometry Cu3Si were prepared by sputter deposition with individual layer thicknesses varying in different samples between 2 and 100 nm. We observed diffusion limited growth of Cu3 Si upon annealing these diffusion couples below 500 K. Reaction constants were measured for a temperature range of 455 to 495 K for thicknesses of growing Cu3Si between 2.6 and 80 nm. The temperature dependence of the reaction constant, k2, was characterized as k2 = k0 exp(− Ea/kbT) with activation energy, Ea = 1.0 eV/atom and pre-factor, k0 = 1.9×10−3 cm2/s.

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Factors Influencing Geosmin Production by the Cyanobacterium Oscillatoria Brevis

Water Science & Technology ◽

10.2166/wst.1988.0233 ◽

1988 ◽

Vol 20 (8-9) ◽

pp. 125-131 ◽

Cited By ~ 17

Author(s):

H. Naes ◽

H. C. Utkilen ◽

A. F. Post

Keyword(s):

Environmental Factors ◽

Dry Weight ◽

Growth Conditions ◽

Limited Extent ◽

Limited Growth ◽

Pigment Synthesis ◽

Factors Affecting ◽

Culture Techniques ◽

Factors Influencing ◽

Effect Of Inhibitors

Environmental factors affecting geosmin production by Oscillatoria brevis have been investigated under laboratory conditions using continuous culture techniques. Transition from light to nutrient limited growth conditions caused a two-fold decrease in geosmin production. However, geosmin content increased relative to pigment content (chlorophyll a and carotenoids). It has been suggested that geosmin biosynthesis in O. brevis proceeds via the isoprenoid pathway as was found in actinomycetes. Accordingly, we investigated the effect of inhibitors of the intermediate stages in this synthetic pathway in order to study the regulation of geosmin production in relation to pigment synthesis. It was concluded that geosmin seemed to function as an overflow metabolite in this pathway. Due to the only modest changes in geosmin production per dry weight compared to changes in biomass levels during light- or nutrient limited growth, contamination of eutrophic fresh waters with geosmin appears to depend mainly on the species present and its biomass level and only to a limited extent on nutrient enhanced synthesis.

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Differences between the kinetics of nutrient uptake by micro-organisms, growth and enzyme kinetics

Trends in Biochemical Sciences ◽

10.1016/0968-0004(83)90232-3 ◽

1983 ◽

Vol 8 (4) ◽

pp. 121-124 ◽

Cited By ~ 24

Author(s):

D.K. Button

Keyword(s):

Enzyme Kinetics ◽

Nutrient Uptake ◽

Micro Organisms ◽

Kinetics Of

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The Transcriptional Landscape of Campylobacter jejuni under Iron Replete and Iron Limited Growth Conditions

PLoS ONE ◽

10.1371/journal.pone.0079475 ◽

2013 ◽

Vol 8 (11) ◽

pp. e79475 ◽

Cited By ~ 30

Author(s):

James Butcher ◽

Alain Stintzi

Keyword(s):

Campylobacter Jejuni ◽

Growth Conditions ◽

Limited Growth ◽

Transcriptional Landscape

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Study on biofiltration capacity and kinetics of nutrient uptake by Gracilaria cervicornis (Turner) J. Agardh (Rhodophyta, Gracilariaceae)

Revista Brasileira de Farmacognosia ◽

10.1590/s0102-695x2011005000074 ◽

2011 ◽

Vol 21 (2) ◽

pp. 329-333 ◽

Cited By ~ 4

Author(s):

Marcella A. A. Carneiro ◽

Fúlvio Aurélio de M. Freire ◽

Eliane Marinho-Soriano

Keyword(s):

Nutrient Uptake ◽

Kinetics Of

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Direct observation of crystallization and melting with colloids

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1813885116 ◽

2019 ◽

Vol 116 (4) ◽

pp. 1180-1184 ◽

Cited By ~ 5

Author(s):

Hyerim Hwang ◽

David A. Weitz ◽

Frans Spaepen

Keyword(s):

Energy Difference ◽

Face Centered Cubic ◽

Limited Growth ◽

Free Energy Difference ◽

Precise Control ◽

Early Computer ◽

Face Centered ◽

Jump Frequencies ◽

Kinetics Of ◽

Kinetics Of Crystal Growth

We study the kinetics of crystal growth and melting of two types of colloidal crystals: body-centered cubic (BCC) crystals and face-centered cubic (FCC) crystals. A dielectrophoretic “electric bottle” confines colloids, enabling precise control of the motion of the interface. We track the particle motion, and by introducing a structural order parameter, we measure the jump frequencies of particles to and from the crystal and determine from these the free-energy difference between the phases and the interface mobility. We find that the interface is rough in both BCC and FCC cases. Moreover, the jump frequencies correspond to those expected from the random walk of the particles, which translates to collision-limited growth in metallic systems. The mobility of the BCC interface is greater than that of the FCC interface. In addition, contrary to the prediction of some early computer simulations, we show that there is no significant asymmetry between the mobilities for crystallization and melting.

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Investment in secreted enzymes during nutrient-limited growth is utility dependent

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1708580114 ◽

2017 ◽

Vol 114 (37) ◽

pp. E7796-E7802 ◽

Cited By ~ 18

Author(s):

Brent Cezairliyan ◽

Frederick M. Ausubel

Keyword(s):

Bacterial Growth ◽

Pathogenic Bacteria ◽

Quantitative Relationship ◽

Growth Conditions ◽

Limited Growth ◽

Protein Substrate ◽

Regulatory Strategy ◽

Rate Of Increase ◽

Secreted Proteases ◽

Secreted Enzymes

Pathogenic bacteria secrete toxins and degradative enzymes that facilitate their growth by liberating nutrients from the environment. To understand bacterial growth under nutrient-limited conditions, we studied resource allocation between cellular and secreted components by the pathogenic bacteriumPseudomonas aeruginosaduring growth on a protein substrate that requires extracellular digestion by secreted proteases. We identified a quantitative relationship between the rate of increase of cellular biomass under nutrient-limiting growth conditions and the rate of increase in investment in secreted proteases. Production of secreted proteases is stimulated by secreted signals that convey information about the utility of secreted proteins during nutrient-limited growth. Growth modeling using this relationship recapitulated the observed kinetics of bacterial growth on a protein substrate. The proposed regulatory strategy suggests a rationale for quorum-sensing–dependent stimulation of the production of secreted enzymes whereby investment in secreted enzymes occurs in proportion to the utility they confer. Our model provides a framework that can be applied toward understanding bacterial growth in many environments where growth rate is limited by the availability of nutrients.

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