Surface studies of mammalian cells grown in culture by x-ray photoelectron spectroscopy

Millard, Merle M.; Bartholomew, James C.

doi:10.1021/ac50017a004

Cited by 24 publications

(10 citation statements)

References 62 publications

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“…A number of previous studies have analyzed the surface chemistries of bacterial cells by ESCA (1,3,22,38,39,41). ESCA analysis of S. alga cell surfaces showed a higher atomic concentration of oxygen and lower atomic concentrations of carbon and nitrogen on the surfaces of S. alga RAD20 cells than on the surfaces of S. alga BrY cells.…”

Section: Discussionmentioning

confidence: 99%

Role of Hydrophobicity in Adhesion of the Dissimilatory Fe(III)-Reducing Bacterium Shewanella alga to Amorphous Fe(III) Oxide

Caccavo¹,

Schamberger²,

Keiding³

et al. 1997

Appl Environ Microbiol

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The mechanisms by which the dissimilatory Fe(III)-reducing bacterium Shewanella alga adheres to amorphous Fe(III) oxide were examined through comparative analysis of S. alga BrY and an adhesion-deficient strain of this species, S. alga RAD20. Approximately 100% of S. alga BrY cells typically adhered to amorphous Fe(III) oxide, while less than 50% of S. alga RAD20 cells adhered. Bulk chemical analysis, isoelectric point analysis, and cell surface analysis by time-of-flight secondary-ion mass spectrometry and electron spectroscopy for chemical analysis demonstrated that the surfaces of S. alga BrY cells were predominantly protein but that the surfaces of S. alga RAD20 cells were predominantly exopolysaccharide. Physicochemical analyses and hydrophobic interaction assays demonstrated that S. alga BrY cells were more hydrophobic than S. alga RAD20 cells. This study represents the first quantitative analysis of the adhesion of a dissimilatory Fe(III)-reducing bacterium to amorphous Fe(III) oxide, and the results collectively suggest that hydrophobic interactions are a factor in controlling the adhesion of this bacterium to amorphous Fe(III) oxide. Despite having a reduced ability to adhere, S. alga RAD20 reduced Fe(III) oxide at a rate identical to that of S. alga BrY. This result contrasts with results of previous studies by demonstrating that irreversible cell adhesion is not requisite for microbial reduction of amorphous Fe(III) oxide. These results suggest that the interaction between dissimilatory Fe(III)-reducing bacteria and amorphous Fe(III) oxide is more complex than previously believed.

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Section: Discussionmentioning

confidence: 99%

Role of Hydrophobicity in Adhesion of the Dissimilatory Fe(III)-Reducing Bacterium Shewanella alga to Amorphous Fe(III) Oxide

Caccavo¹,

Schamberger²,

Keiding³

et al. 1997

Appl Environ Microbiol

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“…An elemental analysis over the thickness of the outer 2 to 5 nm can be obtained by X-ray irradiation of surfaces, causing ejection of electrons, which can be discriminated by their binding energy in a specific chemical element. X-ray photoelectron spectroscopy (XPS) is most frequently used for nonbiological surfaces but has been used in a few cases for the study of bacterial and eucaryotic cells (2,7,13). Compared with other surface techniques (1), XPS has the advantage of being nondestructive and highly surface sensitive; it gives a high information content and yields quantitative data on elemental composition and chemical bonding.…”

mentioning

confidence: 99%

Surface properties of Streptococcus salivarius HB and nonfibrillar mutants: measurement of zeta potential and elemental composition with X-ray photoelectron spectroscopy

et al. 1988

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To characterize the functional cell surface, the zeta potentials and elemental surface composition of Streptococcus salivarius HB and a range of mutants with known molecular surface structures were determined. Zeta potentials of fully hydrated cells were measured as a function of pH in dilute potassium phosphate solutions, yielding isoelectric points of the strains. Elemental composition (0, C, N, and P) of the outer 2 to 5 nm of the freeze-dried cell surfaces were measured by X-ray photoelectron spectroscopy. An increasing loss of proteinaceous fibrillar surface antigens of the mutants was found to be accompanied by a progressive decrease in the N/C ratio from 0.104 in the parent strain HB to 0.053 in mutant HBC12. Simultaneously, the value of the isoelectric point shifted from 3.0 to 1.3. In a previous study (A. H. Weerkamp, H. C. van der Mei, and J. W. Slot, Infect. Immun. 55:438-455, 1987) on the cell surfaces of the same strains, it was shown that removal of fibrils led to increased exposure of (lipo)teichoic acid at the surface, which explains the low isoelectric point caused by the low pKa of the phosphate groups.The outer surface of bacterial cells mediates many crucial interactions of the cells with their environment, such as adherence, flocculation, antigenicity, susceptibility to phagocytosis, and binding of macromolecules. Understanding these complex functions requires detailed knowledge of the elemental, molecular, and structural composition of the cell surface, which is obviously different from the bulk of the cell wall (3, 18). Generally such knowledge is obtained by electron microscopic methods, by probing the cell surface with specific molecules such as antibodies or lectins, by functional tests such as hydrophobicity assays, or by indirect techniques involving the removal of surface components (8,12).Only a few techniques provide information on the chemical composition on the outer surface of intact cells. An elemental analysis over the thickness of the outer 2 to 5 nm can be obtained by X-ray irradiation of surfaces, causing ejection of electrons, which can be discriminated by their binding energy in a specific chemical element. X-ray photoelectron spectroscopy (XPS) is most frequently used for nonbiological surfaces but has been used in a few cases for the study of bacterial and eucaryotic cells (2, 7, 13). Compared with other surface techniques (1), XPS has the advantage of being nondestructive and highly surface sensitive; it gives a high information content and yields quantitative data on elemental composition and chemical bonding. A disadvantage, common to most analytical surface techniques, is that samples must be measured under high vacuum (10-6 to 10-9 Pa).Previously, we studied the structure and molecular composition of the cell surface of Streptococcus salivarius HB and a range of mutants devoid of specific fibrillar appendages and lacking adhesive abilities (11,17). No information is * Corresponding author. available on the elemental surface composition of these cells and how it w...

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“…It should be pointed out that the correlation presented in Fig. 1 involves (6), MUCL 28733 cultivated in glucose 5% and yeast extract 2% (7) and cultivated in malt extract 12% (8) the total surface concentration of nitrogen and not only a concentration of protonated nitrogen. In fact the latter should give a peak at 402 eV [13] and may be responsible for a small contribution which cannot be separated easily from the main nitrogen peak.…”

Section: Methodsmentioning

confidence: 93%

“…This method has been extensively used during the last 15 years, in the fields of heterogeneous catalysis and material sciences [1][2][3]. However, there have been few and limited attempts to apply it to the study of cell surfaces [4][5][6][7][8][9]. This is probably due to the necessity of dehydrating the sample, which raises questions concerning the representativity of the surface analyzed.…”

Section: Introductionmentioning

confidence: 99%

Chemical analysis of the surface of microorganisms by X-ray photoelectron spectroscopy

Amory

1988

FEMS Microbiology Letters

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Surface studies of mammalian cells grown in culture by x-ray photoelectron spectroscopy

Cited by 24 publications

References 62 publications

Role of Hydrophobicity in Adhesion of the Dissimilatory Fe(III)-Reducing Bacterium Shewanella alga to Amorphous Fe(III) Oxide

Role of Hydrophobicity in Adhesion of the Dissimilatory Fe(III)-Reducing Bacterium Shewanella alga to Amorphous Fe(III) Oxide

Surface properties of Streptococcus salivarius HB and nonfibrillar mutants: measurement of zeta potential and elemental composition with X-ray photoelectron spectroscopy

Chemical analysis of the surface of microorganisms by X-ray photoelectron spectroscopy

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