scholarly journals The extraction of cell walls of Pseudomonas aeruginosa with aqueous phenol. The insoluble residue and material from the aqueous layers

1967 ◽  
Vol 105 (2) ◽  
pp. 759-765 ◽  
Author(s):  
K. Clarke ◽  
G. W. Gray ◽  
D. A. Reaveley
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Cell Walls ◽  
Lipid A ◽  
Diaminopimelic Acid ◽  
Insoluble Residue ◽  
Muramic Acid ◽  
Gram Negative ◽  
Gram Negative Organisms ◽  
Residue Fraction

1. The insoluble residue and material present in the aqueous layers resulting from treatment of cell walls of Pseudomonas aeruginosa with aqueous phenol were examined. 2. The products (fractions AqI and AqII) isolated from the aqueous layers from the first and second extractions respectively account for approx. 25% and 12% of the cell wall and consist of both lipopolysaccharide and muropeptide. 3. The lipid part of the lipopolysaccharide is qualitatively similar to the corresponding material (lipid A) from other Gram-negative organisms, as is the polysaccharide part. 4. The insoluble residue (fraction R) contains sacculi, which also occur in fraction AqII. On hydrolysis, the sacculi yield glucosamine, muramic acid, alanine, glutamic acid and 2,6-diaminopimelic acid, together with small amounts of lysine, and they are therefore similar to the murein sacculi of other Gram-negative organisms. Fraction R also contains substantial amounts of protein, which differs from that obtained from the phenol layer. 5. The possible association or aggregation of lipopolysaccharide, murein and murein sacculi is discussed.

LYSOZYME SENSITIVITY OF THE CELL WALL OF PSEUDO-MONAS AERUGINOSA: FURTHER EVIDENCE FOR THE ROLE OF THE NON-PEPTIDOGLYCAN COMPONENTS IN CELL WALL RIGIDITY

1966 ◽  
Vol 12 (1) ◽  
pp. 105-108 ◽  
Author(s):  
K. Jane Carson ◽  
R. G. Eagon
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Electron Micrographs ◽  
Cell Walls ◽  
Gram Negative Bacteria ◽  
Normal Cells ◽  
Thin Sections ◽  
Gram Negative ◽  
Cell Wall Rigidity

Electron micrographs of thin sections of normal cells of Pseudomonas aeruginosa showed the cell walls to be convoluted and to be composed of two distinct layers. Electron micrographs of thin sections of lysozyme-treated cells of P. aeruginosa showed (a) that the cell walls lost much of their convoluted nature; (b) that the layers of the cell walls became diffuse and less distinct; and (c) that the cell walls became separated from the protoplasts over extensive cellular areas. These results suggest that the peptidoglycan component of the unaltered cell walls of P. aeruginosa is sensitive to lysozyme. Furthermore, it appears that the peptidoglycan component is not solely responsible for the rigidity of the cell walls of Gram-negative bacteria.

scholarly journals Antimicrobial Properties of the Polyaniline Composites against Pseudomonas aeruginosa and Klebsiella pneumoniae

2020 ◽  
Vol 11 (3) ◽  
pp. 59 ◽  
Author(s):  
Moorthy Maruthapandi ◽  
Arumugam Saravanan ◽  
John H. T. Luong ◽  
Aharon Gedanken
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Klebsiella Pneumoniae ◽  
Cell Walls ◽  
Antimicrobial Properties ◽  
Cell Lysis ◽  
Antimicrobial Activities ◽  
Sonochemical Method ◽  
Gram Negative ◽  
Polyaniline Composites

CuO, TiO2, or SiO2 was decorated on polyaniline (PANI) by a sonochemical method, and their antimicrobial properties were investigated for two common Gram-negative pathogens: Pseudomonas aeruginosa (PA) and Klebsiella pneumoniae (KP). Without PANI, CuO, TiO2, or SiO2 with a concentration of 220 µg/mL exhibited no antimicrobial activities. In contrast, PANI-CuO and PANI-TiO2 (1 mg/mL, each) completely suppressed the PA growth after 6 h of exposure, compared to 12 h for the PANI-SiO2 at the same concentration. The damage caused by PANI-SiO2 to KP was less effective, compared to that of PANI-TiO2 with the eradication time of 12 h versus 6 h, respectively. This bacterium was not affected by PANI-CuO. All the composites bind tightly to the negative groups of bacteria cell walls to compromise their regular activities, leading to the damage of the cell wall envelope and eventual cell lysis.

scholarly journals FINE STRUCTURE OF THE GRAM-NEGATIVE BACTERIUM ACETOBACTER SUBOXYDANS

1964 ◽  
Vol 20 (2) ◽  
pp. 217-233 ◽  
Author(s):  
G. W. Claus ◽  
L. E. Roth
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Cell Walls ◽  
Negative Staining ◽  
Homogeneous Layer ◽  
Physical Treatment ◽  
Thin Sections ◽  
Gram Negative ◽  
Acetobacter Suboxydans ◽  
Negative Cell

The morphological features of the cell wall, plasma membrane, protoplasmic constituents, and flagella of Acetobacter suboxydans (ATCC 621) were studied by thin sectioning and negative staining. Thin sections of the cell wall demonstrate an outer membrane and an inner, more homogeneous layer. These observations are consistent with those of isolated, gram-negative cell-wall ghosts and the chemical analyses of gram-negative cell walls. Certain functional attributes of the cell-wall inner layer and the structural comparisons of gram-negative and gram-positive cell walls are considered. The plasma membrane is similar in appearance to the membrane of the cell wall and is occasionally found to be folded into the cytoplasm. Certain features of the protoplasm are described and discussed, including the diffuse states of the chromatinic material that appear to be correlated with the length of the cell and a polar differentiation in the area of expected flagellar attachment. Although the flagella appear hollow in thin sections, negative staining of isolated flagella does not substantiate this finding. Severe physical treatment occasionally produces a localized penetration into the central region of the flagellum, the diameter of which is much smaller then that expected from sections. A possible explanation of this apparent discrepancy is discussed.

Frequency of Bacteriological Organism in Patients with Thoracic Empyema

2021 ◽  
Vol 15 (6) ◽  
pp. 1914-1916
Author(s):  
Muhammad Umer Salim ◽  
Syed Mohammad Umair Dilawar ◽  
Syed Tabish Rehman
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Gram Negative ◽  
Thoracic Empyema ◽  
Staph Aureus ◽  
Culture Test ◽  
Test Study ◽  
Bacterial Organism ◽  
Gram Negative Organisms

Objective: To examine the frequency of bacteriological organism present in pleural fluid, in patients positive with thoracic empyema, assessed on the basis of pus culture test. Study Design: Cross-sectional study Place and Duration: Inpatient Department, Chest Medicine Ward 12, JPMC, Karachi, Pakistan for six months duration from 11 February 2019 to 10 August 2019. Methodology: One hundred and thirty nine patients diagnosed with Thoracic Empyema were included in this study. All patients included in the study shall undergo Pus Culture Test prior to identify the presence or absence of bacterial organism. Those with positive bacterial findings (mainly Staph Aureus and gram negative organisms) were further assessed for stratification with reference to their possible variable affecters. Results: There were 107 males and 32 females (%M: F ratio 77:23), with Empyema Thoracic, aged between 25-55 years and having a mean age of 36.28 year (± SD 8.206), were studied. The Pus Culture Test rate was 100% whereas duration of empyema was of average 18.38 days (± S.D 11.16). One hundred and four patients (74.82%) were carrying investigated bacteria which were staph. Aureus in 17 (12.50%) patients. GRAM NEGATIVE ORGANISMS in 87 (62.58%) patients. Echerea Coli in 12 (8.3%) patients, Pseudomonas. Aeruginosa in 46 (33.33%) patients, Klebseilla in 17(12.50%) patients, Enterococcus Species in 12 (8.3%) patients. While remaining thirty five patients (25.17%) were found to have other bacteria, including Streptococcus, Proteus Mirabillis and Acinobacter, responsible for Empyema. Conclusion: It is concluded that 74.82% patients had bacteria and among them 62.58% patients had gram negative organism. Pseudomonas Aeruginosa was the most common organism followed by Klebseilla and staph. Aureus. Keywords: Empyema, Thoracic, Pleural Effusion, Thoracentesis, Thoracostomy

The effects of phospholipid depletion on the cleavage pattern of the cell walls of frozen Gram-negative bacteria

1973 ◽  
Vol 19 (8) ◽  
pp. 1056-1057 ◽  
Author(s):  
A. Forge ◽  
J. W. Costerton
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Cytoplasmic Membrane ◽  
Gram Negative Bacteria ◽  
Cleavage Pattern ◽  
Gram Negative ◽  
Whole Cells ◽  
The Cross ◽  
Double Track ◽  
Chloroform Methanol

Extraction of whole cells of the marine pseudomonad (B-16) with chloroform–methanol causes the disappearance of the cleavage planes, and the cross-sectioned profile of both the cytoplasmic membrane and the double-track layer of the cell wall.

scholarly journals The configuration of 2,6-diamino-3-hydroxypimelic acid in microbial cell walls

1969 ◽  
Vol 115 (4) ◽  
pp. 797-805 ◽  
Author(s):  
H R Perkins
Keyword(s):  
Cell Wall ◽  
Hydroxy Group ◽  
Cell Walls ◽  
Optical Rotation ◽  
Periodate Oxidation ◽  
Ring Closure ◽  
Diaminopimelic Acid ◽  
Amino Group ◽  
Amino Groups ◽  
Peptide Linkage

β-Hydroxydiaminopimelic acid, together with some diaminopimelic acid, occurs in the cell-wall mucopeptide of certain Actinomycetales. These components were converted into their di-DNP derivatives and separated by chromatography. Hence the relative proportions present in the cell walls of a number of species were measured. The problem of acid-induced inversion of configuration was studied. Of the diaminohydroxypimelic acids isomer B (see Scheme 2; amino groups meso, hydroxy group threo to its neighbouring amino group) always predominated but a small proportion of isomer D (amino groups l, hydroxy group erythro) also occurred. The configuration of the diaminohydroxypimelic acids was determined by periodate oxidation to glutamic γ-semialdehyde, which underwent spontaneous ring-closure. Reduction with sodium borohydride produced optically active proline, the configuration of which was determined by direct measurement of the optical rotation of DNP-proline. Un-cross-linked diaminohydroxypimelic acid in the cell wall was oxidized with periodate in the presence of ammonia. Since the remaining amino group was bound in peptide linkage, ring-closure was prevented and borohydride reduction of the aldehyde–ammonia presumed to be present resulted in the formation of ornithine. The quantity of ornithine was used as a measure of the degree of cross-linking.

Die gemeinsame Wurzel der Lyse von Escherichia coli durch Penicillin oder durch Phagen

1957 ◽  
Vol 12 (7) ◽  
pp. 421-427 ◽  
Author(s):  
W. Weidel ◽  
J. Primosigh
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Building Blocks ◽  
Diaminopimelic Acid ◽  
Wall Structure ◽  
Gram Positive ◽  
E Coli ◽  
Growing Cell ◽  
Cell Wall Disruption ◽  
Entire Cell

One of the two layers of the E. coli B cell wall is shown to possess the chemical composition typical of a gram-positive microorganism. It is this layer which lends support and strength to the entire cell wall structure, its rigidity depending up on the incorporation of building blocks made up from alanine, glutamic acid, diaminopimelic acid, muramic acid and glucosamine.Phage enzyme is an agent capable of removing these stabilizing units from the „gram-positive “ layer, thereby causing it to collapse. Penicillin appears to prevent the biosynthetic incorporation of the same stabilizing units into growing cell walls, thus producing eventually the effect of cell wall disruption in a basically similar way.The rather manifold aspects of these findings are discussed at some length.

Isolation and characterization of the peptidoglycans from selected Gram-positive and Gram-negative periodontal pathogens

1985 ◽  
Vol 31 (2) ◽  
pp. 154-160 ◽  
Author(s):  
M. R. Barnard ◽  
S. C. Holt
Keyword(s):  
Electron Microscopy ◽  
Diaminopimelic Acid ◽  
Muramic Acid ◽  
Periodontal Pathogens ◽  
Gram Positive ◽  
Gram Negative ◽  
Isolation And Characterization ◽  
Bacteroides Gingivalis ◽  
Scanning Electron

The peptidoglycans from several Gram-negative and Gram-positive periodontal pathogens were isolated, purified, and characterized both morphologically and chemically. In addition, the effects of the mureolytic enzymes, lysozyme, M-1 N-acetyl-muramidase, and the AM-3 endopeptidase, on the peptidoglycans were examined. These enzymes were found to be highly effective in the degradation of the purified peptidoglycans; however, a Bacteroides capillus peptidoglycan–protein complex exhibited a greater resistance to these enzymes. Morphologically, the peptidoglycans consisted of large saccular sheets which, when viewed by scanning electron microscopy, contained numerous holes and tears. Chemically, the peptidoglycans consisted of muramic acid, glucosamine, alanine, glutamic acid, and meso-diaminopimelic acid (DAP). One Bacteroides species, Bacteroides gingivalis strain W, contained glycine and LL-DAP, suggestive of an indirectly cross-linked A3γ peptidoglycan.

scholarly journals Antimicrobial Biophotonic Treatment of Ampicillin-Resistant Pseudomonas aeruginosa with Hypericin and Ampicillin Cotreatment Followed by Orange Light

Pharmaceutics ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 641 ◽  
Author(s):  
Seemi Tasnim Alam ◽  
Tram Anh Ngoc Le ◽  
Jin-Soo Park ◽  
Hak Cheol Kwon ◽  
Kyungsu Kang
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Wall Structures ◽  
Global Issue ◽  
Life Threatening ◽  
Bacteria And Fungi

Bacterial antibiotic resistance is an alarming global issue that requires alternative antimicrobial methods to which there is no resistance. Antimicrobial photodynamic therapy (APDT) is a well-known method to combat this problem for many pathogens, especially Gram-positive bacteria and fungi. Hypericin and orange light APDT efficiently kill Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and the yeast Candida albicans. Although Gram-positive bacteria and many fungi are readily killed with APDT, Gram-negative bacteria are difficult to kill due to their different cell wall structures. Pseudomonas aeruginosa is one of the most important opportunistic, life-threatening Gram-negative pathogens. However, it cannot be killed successfully by hypericin and orange light APDT. P. aeruginosa is ampicillin resistant, but we hypothesized that ampicillin could still damage the cell wall, which can promote photosensitizer uptake into Gram-negative cells. Using hypericin and ampicillin cotreatment followed by orange light, a significant reduction (3.4 log) in P. aeruginosa PAO1 was achieved. P. aeruginosa PAO1 inactivation and gut permeability improvement by APDT were successfully shown in a Caenorhabditis elegans model.

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