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

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.

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

Development ◽

10.1242/dev.67.1.181 ◽

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’.

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Osmotic Stress Signaling and Osmoadaptation in Yeasts

Microbiology and Molecular Biology Reviews ◽

10.1128/mmbr.66.2.300-372.2002 ◽

2002 ◽

Vol 66 (2) ◽

pp. 300-372 ◽

Cited By ~ 1109

Author(s):

Stefan Hohmann

Keyword(s):

Cell Surface ◽

Map Kinase ◽

Surface Properties ◽

Transcriptional Response ◽

Yeast Cells ◽

Hog Pathway ◽

Cell Surface Properties ◽

High Osmolarity ◽

Map Kinase Cascade ◽

Kinase Cascade

SUMMARY The ability to adapt to altered availability of free water is a fundamental property of living cells. The principles underlying osmoadaptation are well conserved. The yeast Saccharomyces cerevisiae is an excellent model system with which to study the molecular biology and physiology of osmoadaptation. Upon a shift to high osmolarity, yeast cells rapidly stimulate a mitogen-activated protein (MAP) kinase cascade, the high-osmolarity glycerol (HOG) pathway, which orchestrates part of the transcriptional response. The dynamic operation of the HOG pathway has been well studied, and similar osmosensing pathways exist in other eukaryotes. Protein kinase A, which seems to mediate a response to diverse stress conditions, is also involved in the transcriptional response program. Expression changes after a shift to high osmolarity aim at adjusting metabolism and the production of cellular protectants. Accumulation of the osmolyte glycerol, which is also controlled by altering transmembrane glycerol transport, is of central importance. Upon a shift from high to low osmolarity, yeast cells stimulate a different MAP kinase cascade, the cell integrity pathway. The transcriptional program upon hypo-osmotic shock seems to aim at adjusting cell surface properties. Rapid export of glycerol is an important event in adaptation to low osmolarity. Osmoadaptation, adjustment of cell surface properties, and the control of cell morphogenesis, growth, and proliferation are highly coordinated processes. The Skn7p response regulator may be involved in coordinating these events. An integrated understanding of osmoadaptation requires not only knowledge of the function of many uncharacterized genes but also further insight into the time line of events, their interdependence, their dynamics, and their spatial organization as well as the importance of subtle effects.

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

Bioscience Reports ◽

10.1007/bf01200999 ◽

1996 ◽

Vol 16 (1) ◽

pp. 35-40 ◽

Cited By ~ 12

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.

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Engineering of global regulators and cell surface properties toward enhancing stress tolerance in Saccharomyces cerevisiae

Journal of Bioscience and Bioengineering ◽

10.1016/j.jbiosc.2017.06.010 ◽

2017 ◽

Vol 124 (6) ◽

pp. 599-605 ◽

Cited By ~ 5

Author(s):

Kouichi Kuroda ◽

Mitsuyoshi Ueda

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Surface ◽

Stress Tolerance ◽

Surface Properties ◽

Cell Surface Properties ◽

Global Regulators

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

Journal of Cell Science ◽

10.1242/jcs.75.1.339 ◽

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.

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Pga13 in Candida albicans is localized in the cell wall and influences cell surface properties, morphogenesis and virulence

Fungal Genetics and Biology ◽

10.1016/j.fgb.2012.01.010 ◽

2012 ◽

Vol 49 (4) ◽

pp. 322-331 ◽

Cited By ~ 28

Author(s):

Samuel Gelis ◽

Piet W.J. de Groot ◽

Luis Castillo ◽

María-Dolores Moragues ◽

Rafael Sentandreu ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

Cell Surface ◽

Surface Properties ◽

Cell Surface Properties

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The Gene Encoding NAD-Dependent Epimerase/Dehydratase, wcaG, Affects Cell Surface Properties, Virulence, and Extracellular Enzyme Production in the Soft Rot Phytopathogen, Pectobacterium carotovorum

Microorganisms ◽

10.3390/microorganisms7060172 ◽

2019 ◽

Vol 7 (6) ◽

pp. 172 ◽

Cited By ~ 2

Author(s):

Rabiul Islam ◽

Shyretha Brown ◽

Ali Taheri ◽

C. Korsi Dumenyo

Keyword(s):

Escherichia Coli ◽

Cell Wall ◽

Cell Surface ◽

Surface Properties ◽

Plant Cell ◽

Plant Cell Wall ◽

Soft Rot ◽

Pectobacterium Carotovorum ◽

Cell Wall Degrading Enzymes ◽

Cell Surface Properties

Pectobacterium carotovorum is a gram-negative bacterium that, together with other soft rot Enterobacteriaceae causes soft rot disease in vegetables, fruits, and ornamental plants through the action of exoproteins including plant cell wall-degrading enzymes (PCWDEs). Although pathogenicity in these bacteria is complex, virulence levels are proportional to the levels of plant cell wall-degrading exoenzymes (PCWDEs) secreted. Two low enzyme-producing transposon Tn5 mutants were isolated, and compared to their parent KD100, the mutants were less virulent on celery petioles and carrot disks. The inactivated gene responsible for the reduced virulence phenotype in both mutants was identified as wcaG. The gene, wcaG (previously denoted fcl) encodes NAD-dependent epimerase/dehydratase, a homologue of GDP-fucose synthetase of Escherichia coli. In Escherichia coli, GDP-fucose synthetase is involved in the biosynthesis of the exopolysaccharide, colanic acid (CA). The wcaG mutants of P. carotovorum formed an enhanced level of biofilm in comparison to their parent. In the hydrophobicity test the mutants showed more hydrophobicity than the parent in hexane and hexadecane as solvents. Complementation of the mutants with extrachromosomal copies of the wild type gene restored these functions to parental levels. These data indicate that NAD-dependent epimerase/dehydratase plays a vital rule in cell surface properties, exoenzyme production, and virulence in P. carotovorum.

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