Effect of EDTA on Salmonella enterica serovar Typhimurium involves a component not assignable to lipopolysaccharide release

Alakomi, Hanna-Leena; Saarela, Maria; Helander, Ilkka M.

doi:10.1099/mic.0.26312-0

Cited by 69 publications

(55 citation statements)

References 18 publications

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“…This nonuniform alteration of the OM by EDTA as revealed by AFM is in accordance with the classical findings that only a certain proportion of LPS can be released by EDTA, indicating the presence of structurally and electrostatically different subpopulations of LPS in the OM. The existence of such structurally distinct LPS populations in spatially separate areas of the OM, as discussed in more detail by Alakomi et al (2), is further supported by our present findings with AFM.…”

Section: Discussionsupporting

confidence: 79%

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Weakening Effect of Cell Permeabilizers on Gram-Negative Bacteria Causing Biodeterioration

Alakomi

Paananen

Suihko

et al. 2006

Appl Environ Microbiol

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120

104

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Gram-negative bacteria play an important role in the formation and stabilization of biofilm structures on stone surfaces. Therefore, the control of growth of gram-negative bacteria offers a way to diminish biodeterioration of stone materials. The effect of potential permeabilizers on the outer membrane (OM) properties of gram-negative bacteria was investigated and further characterized. In addition, efficacy of the agents in enhancing the activity of a biocide (benzalkonium chloride) was assessed. EDTA, polyethylenimine (PEI), and succimer (meso-2,3-dimercaptosuccinic) were shown to be efficient permeabilizers of the members of Pseudomonas and Stenotrophomonas genera, as indicated by an increase in the uptake of a hydrophobic probe (1-N-phenylnaphthylamine) and sensitization to hydrophobic antibiotics. Visualization of Pseudomonas cells treated with EDTA or PEI by atomic force microscopy revealed damage in the outer membrane structure. PEI especially increased the surface area and bulges of the cells. Topographic images of EDTA-treated cells were compatible with events assigned for the effect of EDTA on outer membranes, i.e., release of lipopolysaccharide and disintegration of OM structure. In addition, the effect of EDTA treatment was visualized in phase-contrast images as large areas with varying hydrophilicity on cell surfaces. In liquid culture tests, EDTA and PEI supplementation enhanced the activity of benzalkonium chloride toward the target strains. Use of permeabilizers in biocide formulations would enable the use of decreased concentrations of the active biocide ingredient, thereby providing environmentally friendlier products.

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Section: Discussionsupporting

confidence: 79%

“…The classical example is the chelator EDTA, which sequesters divalent cations that contribute to the stability of the OM by providing electrostatic interactions with proteins and LPS (2,40). Besides EDTA, a number of other permeabilizers are known, some of which act quite differently.…”

mentioning

confidence: 99%

Weakening Effect of Cell Permeabilizers on Gram-Negative Bacteria Causing Biodeterioration

Alakomi

Paananen

Suihko

et al. 2006

Appl Environ Microbiol

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120

104

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“…Lactic acid and its salts are also potent outer membrane disintegrating agents as evidenced by their ability to cause LPS release. These permeabilizers increase susceptibility to hydrophobic substances such as bacteriocins by enabling them to penetrate the cell wall (Alakomi et al, 2003;Castellano et al, 2008).…”

Section: Bacillus Cereusmentioning

confidence: 99%

Bacteriocin-producing lactic acid bacteria as a probiotic potential from Thai indigenous chickens

Musikasang

Sohsomboon

Tani³

et al. 2012

CZECH J ANIM SCI

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Bacteriocin-producing lactic acid bacteria (LAB) were isolated and screened from the gastrointestinal tract (GIT) of Thai indigenous chickens. The bacteriocinogenic activities and the primary probiotic properties were determined. The bacteriocins produced by 14 strains of selected LAB displayed inhibitory activity against indicator strains after the supernatants were neutralized with NaOH in the following species: Lactobacillus sakei subsp. sakei JCM1157, Enterococcus faecalis VanB, Bacillus sp., and Listeria monocytogenes. The antagonistic activity of selected LAB was inactivated or decreased after being treated with proteolytic enzymes (α-chymotrypsin and trypsin). CR5-1 strain exhibited the highest level of activity (5120 AU/ml) in the stationary phase against L. sakei subsp. sakei JCM1157 in MRS broth at 37°C. The nine isolates of selected LAB were investigated for primary probiotic properties. The survival of the nine isolates was found to decrease approximately by 3 log CFU/ml after passing through the gastrointestinal conditions. All isolates exhibited protein digestion on agar plates but no isolates showed the ability to digest starch and lipid. Most of them showed high susceptibilities to some antibiotics (penicillin G, tetracycline and erythromycin). Thirteen LAB strains producing bacteriocin with strongly inhibitory activity were identified as Lactobacillus salivarius and only one strain was identified by 16S rDNA sequence analysis as Lactobacillus agilis.

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“…The combined effect of enterocin KP and EDTA offered a better result than enterocin KP and STPP did. Treatment of gram-negative bacteria with chelating agents generally results in removal of Ca 2+ and Mg 2+ cations from the lipopolysaccharide layer by chelation, destabilizing the outer membrane structure, altering its permeability, and allowing bacteriocins to reach the cytoplasmic membrane (Vaara, 1992;Helander et al, 1997;Yethon and Whitfield, 2001;Hancock and Rozek, 2002;Alakomi et al, 2003). As a result, EDTA and STPP overcome the penetration barrier in gram-negative bacteria, rendering these species sensitive to hydrophobic antibiotics and bacteriocins (Alakomi et al, 2003;Sampathkumar et al, 2003;Belfiore et al, 2007).…”

Section: Discussionmentioning

confidence: 99%

“…Treatment of gram-negative bacteria with chelating agents generally results in removal of Ca 2+ and Mg 2+ cations from the lipopolysaccharide layer by chelation, destabilizing the outer membrane structure, altering its permeability, and allowing bacteriocins to reach the cytoplasmic membrane (Vaara, 1992;Helander et al, 1997;Yethon and Whitfield, 2001;Hancock and Rozek, 2002;Alakomi et al, 2003). As a result, EDTA and STPP overcome the penetration barrier in gram-negative bacteria, rendering these species sensitive to hydrophobic antibiotics and bacteriocins (Alakomi et al, 2003;Sampathkumar et al, 2003;Belfiore et al, 2007). The enhanced effect of chelators such as EDTA, disodium pyrophosphate, trisodium phosphate, hexametaphosphate, or citrate against gram-negative bacteria has been demonstrated for nisin both under laboratory conditions and in foods (Stevens et al, 1991;Siragusa, 1995a, 1995b;Carneiro De Melo et al, 1998;Boziaris and Adams, 1999;Fang and Tsai, 2003).…”

Section: Discussionmentioning

confidence: 99%

Inhibitory effect of enterocin KP in combination with sublethal factors on Escherichia coli O157:H7 or Salmonella Typhimurium in BHI broth and UHT milk

Yıldırım¹,

Ilk²,

Yildirim³

et al. 2014

Turk J Biol

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The effects of physical and chemical sublethal treatments on the antibacterial activity of enterocin KP produced by Enterococcus faecalis KP against Escherichia coli O157:H7 and Salmonella Typhimurium were investigated. Enterocin KP was not active against intact cells of E. coli O157:H7 or S. Typhimurium. However, the use of enterocin KP together with ethylenediaminetetraacetic acid (50 mM), sodium tripolyphosphate (50 mM), sublethal heating (60 °C for 10 min), cold shock (-20 °C for 2 h), or acid stress (mixture of 40% lactic acid, 16% propionic acid, 16% acetic acid) in BHI medium decreased the cell number of E.

show abstract

Effect of EDTA on Salmonella enterica serovar Typhimurium involves a component not assignable to lipopolysaccharide release

Cited by 69 publications

References 18 publications

Weakening Effect of Cell Permeabilizers on Gram-Negative Bacteria Causing Biodeterioration

Weakening Effect of Cell Permeabilizers on Gram-Negative Bacteria Causing Biodeterioration

Bacteriocin-producing lactic acid bacteria as a probiotic potential from Thai indigenous chickens

Inhibitory effect of enterocin KP in combination with sublethal factors on Escherichia coli O157:H7 or Salmonella Typhimurium in BHI broth and UHT milk

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