Use of aqueous two-phase partition to detect cell surface changes during growth of Dictyostelium discoideum

1985 ◽  
Vol 75 (1) ◽  
pp. 339-346
Author(s):  
P.T. Sharpe ◽  
D.J. Watts
Keyword(s):  
Cell Surface ◽  
Cell Fate ◽  
Surface Properties ◽  
Cell Density ◽  
Dictyostelium Discoideum ◽  
Cell Surface Hydrophobicity ◽  
Subsequent Development ◽  
Two Phase ◽  
Cell Surface Properties ◽  
Surface Changes

Changes in the cell surface properties of amoebae of Dictyostelium discoideum during growth in different culture conditions have been studied by aqueous two-phase partitioning on a thin-layer countercurrent distribution apparatus. Changes in cell surface properties were not dependent on the source of nutrients but only on cell density. There was a progressive increase in cell surface hydrophobicity with cell density in both axenic cultures and cultures grown with a bacterial substrate. It is proposed that it is these cell-density-related surface changes that account for the ability of amoebae grown in different conditions to sort out during subsequent development in a manner related to cell fate.

Studies of early stages of differentiation of the cellular slime mould Dictyostelium discoideum

Development ◽  
1982 ◽  
Vol 67 (1) ◽  
pp. 181-193
Author(s):  
P. T. Sharpe ◽  
T. E. Treffry ◽  
D. J. Watts
Keyword(s):  
Cell Differentiation ◽  
Cell Surface ◽  
Surface Properties ◽  
Dictyostelium Discoideum ◽  
Axenic Culture ◽  
Surface Heterogeneity ◽  
Positional Information ◽  
Phase System ◽  
Two Phase ◽  
Cell Surface Properties

Countercurrent distribution in a polymer, two-phase system has been used to study changes in the cell surface properties of amoebae of Dictyostelium discoideum. Amoebae harvested during exponential growth in axenic culture and during the subsequent first six hours of development on Millipore filters were distributed as a single peak. However, the position of the peak changed during the period of early development which showed that changes in cell surface properties were occurring. At aggregation (8 h), the peak markedly broadened, indicating considerable increase in cell surface heterogeneity amongst the amoebae, and heterogeneity was so great by 9–10 h that the amoebae distributed as two peaks. Amoebae from one peak were shown to be precursors of spores while amoebae from the other peak appeared to be precursors of stalk cells. Similarly, amoebae from the trailing and leading edges of the broad peak, formed from amoebae beginning to aggregate (8 h), were found to have different fates. Thus cell differentiation had been found at times of development prior to formation of aggregates having apical tips or anterior-posterior polarity and neither of these features of aggregates can be essential for initiation of cell differentiation. It is therefore concluded that differentiation is not initiated in D. discoideum in response to ‘positional information’.

Changes in Cell Surface Properties of Shiga Toxigenic Escherichia coli by Quercus infectoria G. Olivier

2009 ◽  
Vol 72 (8) ◽  
pp. 1699-1704 ◽  
Author(s):  
SUPAYANG PIYAWAN VORAVUTHIKUNCHAI ◽  
SAKOL SUWALAK
Keyword(s):  
Escherichia Coli ◽  
Cell Surface ◽  
Surface Properties ◽  
Cell Surface Hydrophobicity ◽  
Ethanolic Extract ◽  
Bacterial Cells ◽  
Electron Microscopic ◽  
Cell Surface Properties ◽  
E Coli ◽  
Quercus Infectoria

The effects of Quercus infectoria (family Fagaceae) nutgalls on cell surface properties of Shiga toxigenic Escherichia coli (STEC) were investigated with an assay of microbial adhesion to hydrocarbon. The surface of bacterial cells treated with Q. infectoria exhibited a higher level of cell surface hydrophobicity (CSH) toward toluene than did the surface of untreated cells. With 50% ethanolic extract, the CSH of the three strains of STEC O157:H7 treated with 4× MIC of the extract resulted in moderate or strong hydrophobicity, whereas at 2× MIC and MIC, the CSH of only one strain of E. coli O157:H7 was significantly affected. The 95% ethanolic extract had a significant effect on CSH of all three strains at both 4× MIC and 2× MIC but not at the MIC. The effect on bacterial CSH was less pronounced with the other STEC strains. At 4× MIC, the 50% ethanolic extract increased the CSH of all non-O157 STEC strains significantly. At 2× MIC and 4× MIC, the 95% ethanolic extract affected the CSH of E. coli O26:H11 significantly but did not affect E. coli O111:NM or E. coli O22. Electron microscopic examination revealed the loss of pili in the treated cells. The ability of Q. infectoria extract to modify hydrophobic domains enables this extract to partition the lipids of the bacterial cell membrane, rendering the membrane more permeable and allowing leakage of ions and other cell contents, which leads to cell death. Further studies are required to evaluate the effects of Q. infectoria extract in food systems or in vivo and provide support for the use of this extract as a food additive for control of these STEC pathogens.

The effect of tunicamycin on cell-surface changes associated with development and differentiation of Dictyostelium discoideum

1984 ◽  
Vol 4 (7) ◽  
pp. 589-592 ◽  
Author(s):  
Paul T. Sharpe ◽  
D. J. Watts
Keyword(s):  
Protein Synthesis ◽  
Cell Surface ◽  
Surface Properties ◽  
Dictyostelium Discoideum ◽  
Developmental Changes ◽  
Development And Differentiation ◽  
Cell Surface Changes ◽  
Surface Changes

Developmental changes in surface properties of Dictyostelium discoideum cells have been detected by partitioning. Changes occurring between 0 and 6 h development were not affected by tunicamycin but subsequent changes associated with formation of presumptive spore cells were inhibited. It would seem that only the latter changes are dependent on glyco-protein synthesis.

Short-term inhibition of the energy metabolism affects motility but not surface properties of sperm cells

1996 ◽  
Vol 16 (1) ◽  
pp. 35-40 ◽  
Author(s):  
M. L. Pascual ◽  
J. A. Cebrian-Perez ◽  
M. J. Lopez-Perez ◽  
T. Muiño-Blanco
Keyword(s):  
Energy Metabolism ◽  
Cell Surface ◽  
Surface Properties ◽  
Sperm Cells ◽  
Delayed Effect ◽  
Short Term ◽  
Two Phase ◽  
Cell Surface Properties ◽  
Molecular Events ◽  
Aqueous Two Phase Systems

Centrifugal countercurrent distribution (CCCD) in aqueous two-phase systems has been proven to be a useful method to study subtle surface properties of spermatozoa. The present work shows that a short-term inhibition of the energy metabolism of sperm cells effected by incubating bovine sperm cells with KCN or ouabain, did not account for changes in the cell surface properties, as assessed either by estimation of the cell viability or by CCCD analysis. However, the short-term inhibition of energy metabolism provoked a clear decrease of cell motility, suggesting that a drop of cellular ATP levels brings about a rapid decrease of motility followed by a very delayed effect on cell surface properties. The relevance of these results on the handling of sperm and on the understanding of the molecular events underlying asthenospermia is discussed.

scholarly journals Expression of a Fungal Hydrophobin in the Saccharomyces cerevisiae Cell Wall: Effect on Cell Surface Properties and Immobilization

2002 ◽  
Vol 68 (7) ◽  
pp. 3385-3391 ◽  
Author(s):  
Tiina Nakari-Setälä ◽  
Joana Azeredo ◽  
Mariana Henriques ◽  
Rosário Oliveira ◽  
José Teixeira ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Cell Surface ◽  
Surface Properties ◽  
Hydrophobic Interactions ◽  
Surface Characteristics ◽  
Yeast Cells ◽  
Phase System ◽  
Two Phase ◽  
Cell Surface Properties

ABSTRACT The aim of this work was to modify the cell surface properties of Saccharomyces cerevisiae by expression of the HFBI hydrophobin of the filamentous fungus Trichoderma reesei on the yeast cell surface. The second aim was to study the immobilization capacity of the modified cells. Fusion to the Flo1p flocculin was used to target the HFBI moiety to the cell wall. Determination of cell surface characteristics with contact angle and zeta potential measurements indicated that HFBI-producing cells are more apolar and slightly less negatively charged than the parent cells. Adsorption of the yeast cells to different commercial supports was studied. A twofold increase in the binding affinity of the hydrophobin-producing yeast to hydrophobic silicone-based materials was observed, while no improvement in the interaction with hydrophilic carriers could be seen compared to that of the parent cells. Hydrophobic interactions between the yeast cells and the support are suggested to play a major role in attachment. Also, a slight increase in the initial adsorption rate of the hydrophobin yeast was observed. Furthermore, due to the engineered cell surface, hydrophobin-producing yeast cells were efficiently separated in an aqueous two-phase system by using a nonionic polyoxyethylene detergent, C12-18EO5.

scholarly journals How Capsular Exopolysaccharides Affect Cell Surface Properties of Lactic Acid Bacteria

2020 ◽  
Vol 8 (12) ◽  
pp. 1904
Author(s):  
Carsten Nachtigall ◽  
Cordula Vogel ◽  
Harald Rohm ◽  
Doris Jaros
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Cell Surface ◽  
Surface Properties ◽  
Cell Damage ◽  
Cell Surface Hydrophobicity ◽  
Textural Properties ◽  
Fermented Foods ◽  
Cell Surface Properties ◽  
The Impact

Some lactic acid bacteria are able to produce exopolysaccharides that, based on localization, can be distinguished in free and capsular or cell-bound exopolysaccharides (CPS). Up to now, the former were the focus of current research, mainly because of the technofunctional benefits they exhibit on fermented dairy products. On the other hand, CPS affect the surface properties of bacteria cells and thus also the textural properties of fermented foods, but data are very scarce. As the cell surface properties are strongly strain dependent, we present a new approach to investigate the impact of CPS on cell surface hydrophobicity and moisture load. CPS positive and negative Streptococcus thermophilus and Weissella cibaria were subjected to ultrasonication suitable to detach CPS without cell damage. The success of the method was verified by scanning electron and light microscopy as well as by cultivation experiments. Before applying ultrasonication cells with CPS exhibiting an increased hydrophilic character, enhanced moisture load, and faster water adsorption compared to the cells after CPS removal, emphasizing the importance of CPS on the textural properties of fermented products. The ultrasonic treatment did not alter the cell surface properties of the CPS negative strains.

Influence of oxygen limitation on the cell surface properties of bacteria from activated sludge

1998 ◽  
Vol 37 (4-5) ◽  
pp. 349-352 ◽  
Author(s):  
R. Palmgren ◽  
F. Jorand ◽  
P. H. Nielsen ◽  
J. C. Block
Keyword(s):  
Cell Surface ◽  
Activated Sludge ◽  
Surface Properties ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Growth Conditions ◽  
Oxygen Limitation ◽  
Cell Surface Properties ◽  
Number Of Factors ◽  
Math Test

Cell surface hydrophobicity is believed to be important to flocculation in activated sludge and biofilm systems. Optimization of these processes includes changes in the growth conditions of the bacteria. A number of factors influence cell surface hydrophobicity. The influence of oxygen on the cell surface hydrophobicity of 4 bacteria isolated from activated sludge was tested. The bacteria were grown in batch cultures with and without oxygen limitation. It was found that oxygen limitation generally caused a lowering of the cell surface hydrophobicity. The study also showed that there are many difficulties in measuring cell surface hydrophobicity since other cell surface properties, such as surface charge, influence the measurement methods. The MATH test was employed to establish how assay conditions influenced the results.

Bifidobacterium longum and Bifidobacterium breve isolates from preterm and full term neonates: Comparison of cell surface properties

Anaerobe ◽  
2014 ◽  
Vol 28 ◽  
pp. 212-215 ◽  
Author(s):  
Valérie Andriantsoanirina ◽  
Anne-Claire Teolis ◽  
Liu Xin Xin ◽  
Marie Jose Butel ◽  
Julio Aires
Keyword(s):  
Cell Surface ◽  
Surface Properties ◽  
Bifidobacterium Longum ◽  
Full Term ◽  
Term Neonates ◽  
Bifidobacterium Breve ◽  
Cell Surface Properties
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