In vitro studies of an alkaline phosphatase – cell wall complex from Pseudomonas aeruginosa

1975 ◽  
Vol 21 (1) ◽  
pp. 9-16 ◽  
Author(s):  
D. F. Day ◽  
J. M. Ingram
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Alkaline Phosphatase ◽  
Cell Wall ◽  
Complex Formation ◽  
Wall Material ◽  
Outer Cell ◽  
Whole Cells ◽  
Wall Components ◽  
Outer Cell Wall

Alkaline phosphatase (APase) of Pseudomonas aeruginosa exists primarily in the periplasmic region of the cell, i.e., between the cytoplasmic membrane and the outer tripartite layer. The enzyme is also found in the culture filtrate or associated with the outer layer of the cell wall. APase forms a complex with released outer cell wall material, and lipopolysaccharide (LPS) is associated with the complex. Since the enzyme was purified to homogeneity, it became desirable to determine whether complex formation with LPS, or the outer cell wall, affected any properties of the purified phosphatase. The ratio of activities of purified APase with p-nitrophenylphosphate and β-glycerolphosphate as substrates is about 4:1. The ratio of activities with enzyme complexed with LPS is about 1:1. The energy of activation of sucrose or magnesium released enzyme is 9500 cal/mol whereas the values for purified enzyme plus LPS, purified enzyme, purified enzyme plus phosphatidylethanolamine (PE), and purified enzyme plus LPS plus PE range from 3400 to 8700 cal/mol. These changes occur in the physiological temperature range, 27 to 39C, of this organism. Sucrose-released enzyme in the presence of substrate is inactivated at 47C whereas pure enzyme plus substrate is affected at 41C. The addition of LPS, PE, or a combination of both increases the temperature of inactivation from 45 to 51C. The results suggest that certain properties of the purified enzyme differ from those of the enzyme released from whole cells by either sucrose or magnesium resuspension. The addition of cell wall components such as LPS and PE to purified APase restores these properties. The evidence suggests that artificial complex formation changes the environment of the enzyme protein such that the environment now resembles that which exists within the whole cell wall.

Alkaline phosphatase of Pseudomonas aeruginosa: the mechanism of secretion and release of the enzyme from whole cells

1973 ◽  
Vol 19 (11) ◽  
pp. 1407-1415 ◽  
Author(s):  
J. M. Ingram ◽  
K. -J. Cheng ◽  
J. W. Costerton
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Alkaline Phosphatase ◽  
Cell Wall ◽  
Culture Filtrate ◽  
Outer Wall ◽  
Outer Cell ◽  
Periplasmic Space ◽  
Electron Microscopic ◽  
Whole Cells ◽  
Variable Quantity

The release of alkaline phosphatase from whole cells of Pseudomonas aeruginosa as a function of the MgCl2 concentration is proportional to the release of lipopolysaccharide from the cells. Cells grown under conditions where APase is almost completely secreted to the culture filtrate, i.e. growth at pH 7.6, also secrete lipopolysaccharide. Twenty percent sucrose releases a variable quantity of whole cell phosphatase. Localization of this portion of enzyme by biochemical and electron-microscopic techniques showed that it is located on the cell surface exterior to the outer tripartite layer. Phosphatase, which is not released by sucrose, but which is released by MgCl2, is located in the periplasmic space. Phosphatase is located in three areas; the culture filtrate, the outer cell wall surface, and the periplasmic space. The results suggest that A Pase is associated with, and bound to, a cell wall fraction which contains lipopolysaccharide and that the enzyme is "transported" through the outer wall in complex with this fraction. Liberation of the complex from the outer wall may be accomplished by the mechanical shearing forces developed during growth or during the sucrose suspension procedure.

The Outer Cell-Wall Membrane of Pseudomonas aeruginosa

1974 ◽  
Vol 130 (Supplement) ◽  
pp. S81-S93 ◽  
Author(s):  
J. C. Sadoff ◽  
M. S. Artenstein
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Outer Cell ◽  
Outer Cell Wall

The effect of complement and other cell wall reagents on tetracycline and streptomycin resistance in Pseudomonas aeruginosa

1974 ◽  
Vol 20 (8) ◽  
pp. 1101-1107 ◽  
Author(s):  
J. T. Tseng ◽  
L. E. Bryan
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Cell Membrane ◽  
Resistant Strain ◽  
Streptomycin Resistance ◽  
Outer Cell ◽  
Similar Magnitude ◽  
Peptidoglycan Layer ◽  
Outer Cell Wall

Lysozyme-free antiserum and complement treatment of strain 1885 of Pseudomonas aeruginosa was observed to destroy the penetration barrier of the outer cell wall to lysozyme but not to induce leakage of acid-soluble nucleotides through the cell membrane. The same treatment did not produce a significant increase in uptake of 3H-tetracycline or 3H-streptomycin by the resistant strain 1885 in spite of the destruction of the penetration barrier to lysozyme. A significant increase in both streptomycin and tetracycline uptake occurred in carbenicillin-treated strains but the increase was similar for both susceptible and resistant (to tetracycline and streptomycin) strains of P. aeruginosa. These data suggest (1) the outer cell wall is not a significant penetration barrier to these drugs; (2) the peptidoglycan layer does function as a penetration barrier of similar magnitude in resistant and susceptible cells; (3) the resistance of the strains is a property of the cell membrane or materials intimately associated with the cell membrane. The latter conclusion was further supported by the differential uptake of streptomycin in NaCl-lysozyme-induced spheroplasts of strains 1885 and 2379.

scholarly journals Beyond Antagonism: The Interaction Between Candida Species and Pseudomonas aeruginosa

2019 ◽  
Vol 5 (2) ◽  
pp. 34 ◽  
Author(s):  
Fourie ◽  
Pohl
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Future Perspectives ◽  
Factors Influencing ◽  
Acid Metabolites ◽  
Opportunistic Pathogenic ◽  
Fatty Acid Metabolites ◽  
Wall Components

There are many examples of the interaction between prokaryotes and eukaryotes. One such example is the polymicrobial colonization/infection by the various opportunistic pathogenic yeasts belonging to the genus Candida and the ubiquitous bacterium, Pseudomonas aeruginosa. Although this interaction has simplistically been characterized as antagonistic to the yeast, this review highlights the complexity of the interaction with various factors influencing both microbes. The first section deals with the interactions in vitro, looking specifically at the role of cell wall components, quorum sensing molecules, phenazines, fatty acid metabolites and competition for iron in the interaction. The second part of this review places all these interactions in the context of various infection or colonization sites, i.e., lungs, wounds, and the gastrointestinal tract. Here we see that the role of the host, as well as the methodology used to establish co-infection, are important factors, influencing the outcome of the disease. Suggested future perspectives for the study of this interaction include determining the influence of newly identified participants of the QS network of P. aeruginosa, oxylipin production by both species, as well as the genetic and phenotypic plasticity of these microbes, on the interaction and outcome of co-infection.

Napropamide Binding in Corn (Zea mays) Root Tissue

Weed Science ◽  
1983 ◽  
Vol 31 (5) ◽  
pp. 712-719 ◽  
Author(s):  
Michael Barrett ◽  
Floyd M. Ashton
Keyword(s):  
Cell Wall ◽  
Zea Mays ◽  
Cell Walls ◽  
Wall Material ◽  
Cell Wall Material ◽  
Protease Treatment ◽  
Wall Components ◽  
Soluble Components ◽  
Soluble Fractions

Napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide]-binding in excised root segments of corn (Zea maysL. ‘NC + 59′) was confined to cell wall fractions (residue and 500gpellet) remaining after homogenization and to components of the 100 000gsupernatant. Binding increased in both the cell wall and soluble fractions with continued exposure to napropamide. Microautoradiographs revealed that the napropamide bound in the cell walls was located in epidermal, cortical, and stelar tissue. Various proteins were capable of binding napropamide in vitro; however, protease treatment did not liberate the radioactivity bound in the cell wall fragments. Carbohydrate release from the cell wall material with cellulase was not correlated with the solubilization of bound radioactivity and wall carbohydrate monomers did not appear to bind to napropamide in vitro. A portion of the radioactivity found in the soluble components (at 100 000g) was associated with a molecule of MW > 600. The continued influx of napropamide was due to binding to cell wall components and molecules within the cell.

Outer (cell wall) membrane proteins of Pseudomonas aeruginosa

1973 ◽  
Vol 19 (12) ◽  
pp. 1469-1471 ◽  
Author(s):  
J. D. Stinnett ◽  
R. G. Eagon
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Cell Envelope ◽  
Gradient Centrifugation ◽  
Sucrose Density Gradient ◽  
Outer Cell ◽  
Sucrose Density Gradient Centrifugation ◽  
Protein Components ◽  
Envelope Membranes ◽  
Outer Cell Wall

Cell envelope membranes were isolated from Pseudomonas aeruginosa. These membranes were resolved into cytoplasmic membrane rich and outer (cell wall) membrane rich fractions by discontinuous sucrose density gradient centrifugation. The resolution was based on the separation of enzyme activities and 2-keto-3-deoxyoctonate. Analysis by gel electrophoresis revealed that two of the three major cell envelope protein components were found in the fraction rich in outer (cell wall) membrane. These two protein components were previously shown to occur in a protein–lipopolysaccharide complex in this microorganism.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

scholarly journals Ibudilast Mitigates Delayed Bone Healing Caused by Lipopolysaccharide by Altering Osteoblast and Osteoclast Activity

2021 ◽  
Vol 22 (3) ◽  
pp. 1169
Author(s):  
Yuhan Chang ◽  
Chih-Chien Hu ◽  
Ying-Yu Wu ◽  
Steve W. N. Ueng ◽  
Chih-Hsiang Chang ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bone Formation ◽  
Cancellous Bone ◽  
Bone Healing ◽  
Bone Bridge ◽  
Cell Wall Components ◽  
Osteoclast Activity ◽  
Wall Components

Bacterial infection in orthopedic surgery is challenging because cell wall components released after bactericidal treatment can alter osteoblast and osteoclast activity and impair fracture stability. However, the precise effects and mechanisms whereby cell wall components impair bone healing are unclear. In this study, we characterized the effects of lipopolysaccharide (LPS) on bone healing and osteoclast and osteoblast activity in vitro and in vivo and evaluated the effects of ibudilast, an antagonist of toll-like receptor 4 (TLR4), on LPS-induced changes. In particular, micro-computed tomography was used to reconstruct femoral morphology and analyze callus bone content in a femoral defect mouse model. In the sham-treated group, significant bone bridge and cancellous bone formation were observed after surgery, however, LPS treatment delayed bone bridge and cancellous bone formation. LPS inhibited osteogenic factor-induced MC3T3-E1 cell differentiation, alkaline phosphatase (ALP) levels, calcium deposition, and osteopontin secretion and increased the activity of osteoclast-associated molecules, including cathepsin K and tartrate-resistant acid phosphatase in vitro. Finally, ibudilast blocked the LPS-induced inhibition of osteoblast activation and activation of osteoclast in vitro and attenuated LPS-induced delayed callus bone formation in vivo. Our results provide a basis for the development of a novel strategy for the treatment of bone infection.

A freeze-etch study of plant cell walls for ectodesmata

1974 ◽  
Vol 52 (9) ◽  
pp. 2033-2036 ◽  
Author(s):  
N. C. Lyon ◽  
W. C. Mueller
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Leaf Tissue ◽  
Physicochemical Characteristics ◽  
Outer Cell ◽  
Plantago Major ◽  
Plant Cell Walls ◽  
Phaseolus Vulgaris L ◽  
Epidermal Cell Wall ◽  
Outer Cell Wall

Leaf tissue of Phaseolus vulgaris L. and Plantago major L. was prepared by the freeze-etch technique and examined in the electron microscope for the presence of ectodesmata. No structures analagous to ectodesmata observed with light microscopy could be found in freeze-etched preparations of chemically unfixed material or in material fixed only in glutaraldehyde. Objects appearing as broad, shallow, granular areas in the epidermal cell wall beneath the cuticle were observed in leaf replicas after fixation in complete sublimate fixative, the acid components of the sublimate fixative, or mercuric chloride alone. Because of their distribution and location, these objects can be considered analagous to ectodesmata observed by light microscopists. Because these areas occur only in chemically fixed walls and are localized within the walls in discrete areas, their presence supports the contention that ectodesmata are sites in the outer cell wall with defined physicochemical characteristics.

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