Alternative to Nitrites as Antibacterial Agents Against Clostridium sporogenes

2018 ◽  
Vol 17 (3) ◽  
pp. 242-248
Author(s):  
Zhang Zhi-Guo ◽  
Sun Di ◽  
Wang Mei-Lin
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Normal Growth ◽  
Food Preservation ◽  
Cell Membrane Permeability ◽  
Nitroso Compounds ◽  
Wall Structure ◽  
Ion Leakage ◽  
Bacterial Cells ◽  
Clostridium Sporogenes

Microbial spoilage is one of the key challenges to food preservation and safety. Sodium nitrite, the commonly used antibacterial, is associated with the generation of nitroso compounds known to impose a number of health risks including cancer. In this article, we report a comparison of a number of food-grade antibacterials, not known to generate nitroso compounds, for the inhibition of Clostridium sporogenes. These include e-poly-lysine, potassium cinnamate, chitosan, and glycerol monolaurate. We examined the effects of these agents alone and in combination on cell morphology, cell wall, cell membrane permeability, and bacterial proteins of C. sporogenes. The results show that these agents primarily act to inhibit C. sporogenes growth during log phase. Further analysis with flow cytometry and scanning electron microscopy revealed that the compound can induce changes to the morphology of C. sporogenes cells and, more significantly, to the internal structure of the cells. Treatment of C. sporogenes with the compound inhibited the normal growth of bacterial cells by damaging their wall structure and increasing their wall permeability. The changing pattern of electric conductivity indicated that the compound destroyed cytoplasmic membranes and resulted in ion leakage. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of soluble proteins concluded that the compound can destroy bacterial cells by altering their proteins.

Influence of Carvacrol and 1,8-Cineole on Cell Viability, Membrane Integrity, and Morphology of Aeromonas hydrophila Cultivated in a Vegetable-Based Broth

2015 ◽  
Vol 78 (2) ◽  
pp. 424-429 ◽  
Author(s):  
JOSSANA PEREIRA de SOUSA ◽  
KATARYNE ÁRABE RIMÁ de OLIVEIRA ◽  
REGINA CELIA BRESSAN QUEIROZ de FIGUEIREDO ◽  
EVANDRO LEITE de SOUZA
Keyword(s):  
Cell Viability ◽  
Membrane Permeability ◽  
Aeromonas Hydrophila ◽  
Membrane Integrity ◽  
Cell Membrane Permeability ◽  
Confocal Laser ◽  
Wall Structure ◽  
Bacterial Cells ◽  
Transmission Electron ◽  
Cytoplasmic Content

This study investigated the effects of carvacrol (CAR) and 1,8-cineole (CIN) alone (at the MIC) or in combination at subinhibitory amounts (both at 1/8 MIC) on the cell viability, membrane permeability, and morphology of Aeromonas hydrophila INCQS 7966 (A. hydrophila) cultivated in a vegetable-based broth. CAR and CIN alone or in combination severely affected the viability of the bacteria and caused dramatic changes in the cell membrane permeability, leading to cell death, as observed by confocal laser microscopy. Scanning and transmission electron microscopy images of bacterial cells exposed to CAR or CIN or the mixture of both compounds revealed severe changes in cell wall structure, rupture of the plasma membrane, shrinking of cells, condensation of cytoplasmic content, leakage of intracellular material, and cell collapse. These findings suggest that CAR and CIN alone or in combination at subinhibitory amounts could be applied to inhibit the growth of A. hydrophila in foods, particularly as sanitizing agents in vegetables.

scholarly journals Differential Damage in Bacterial Cells by Microwave Radiation on the Basis of Cell Wall Structure

2000 ◽  
Vol 66 (5) ◽  
pp. 2243-2247 ◽  
Author(s):  
Im-Sun Woo ◽  
In-Koo Rhee ◽  
Heui-Dong Park
Keyword(s):  
Microwave Radiation ◽  
Sodium Dodecyl ◽  
Cell Suspensions ◽  
Wall Structure ◽  
Bacterial Cells ◽  
Dramatic Reduction ◽  
Severe Damage ◽  
Final Temperature ◽  
E Coli ◽  
Scanning Electron

ABSTRACT Microwave radiation in Escherichia coli andBacillus subtilis cell suspensions resulted in a dramatic reduction of the viable counts as well as increases in the amounts of DNA and protein released from the cells according to the increase of the final temperature of the cell suspensions. However, no significant reduction of cell density was observed in either cell suspension. It is believed that this is due to the fact that most of the bacterial cells inactivated by microwave radiation remained unlysed. Scanning electron microscopy of the microwave-heated cells revealed severe damage on the surface of most E. coli cells, yet there was no significant change observed in the B. subtilis cells. Microwave-injuredE. coli cells were easily lysed in the presence of sodium dodecyl sulfate (SDS), yet B. subtilis cells were resistant to SDS.

scholarly journals Motility and the Polar Flagellum Are Required for Aeromonas caviae Adherence to HEp-2 Cells

2001 ◽  
Vol 69 (7) ◽  
pp. 4257-4267 ◽  
Author(s):  
Ali A. Rabaan ◽  
Ioannis Gryllos ◽  
Juan M. Tomás ◽  
Jonathan G. Shaw
Keyword(s):  
Epithelial Cells ◽  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Kanamycin Resistance ◽  
Polar Flagellum ◽  
Bacterial Cells ◽  
Aeromonas Caviae ◽  
Human Epithelial Cells

ABSTRACT Aeromonas caviae is increasingly being recognized as a cause of gastroenteritis, especially among the young. The adherence of aeromonads to human epithelial cells in vitro has been correlated with enteropathogenicity, but the mechanism is far from well understood. Initial investigations demonstrated that adherence of A. caviae to HEp-2 cells was significantly reduced by either pretreating bacterial cells with an antipolar flagellin antibody or by pretreating HEp-2 cells with partially purified flagella. To precisely define the role of the polar flagellum in aeromonad adherence, we isolated the A. caviae polar flagellin locus and identified five polar flagellar genes, in the order flaA, flaB, flaG, flaH, and flaJ. Each gene was inactivated using a kanamycin resistance cartridge that ensures the transcription of downstream genes, and the resulting mutants were tested for motility, flagellin expression, and adherence to HEp-2 cells. N-terminal amino acid sequencing, mutant analysis, and Western blotting demonstrated that A. caviae has a complex flagellum filament composed of two flagellin subunits encoded by flaAand flaB. The predicted molecular mass of both flagellins was ∼31,700 Da; however, their molecular mass estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was ∼35,500 Da. This aberrant migration was thought to be due to their glycosylation, since the proteins were reactive in glycosyl group detection assays. Single mutations in either flaA orflaB did not result in loss of flagella but did result in decreased motility and adherence by approximately 50%. Mutation offlaH, flaJ, or both flagellin genes resulted in the complete loss of motility, flagellin expression, and adherence. However, mutation of flaG did not affect motility but did significantly reduce the level of adherence. Centrifugation of the flagellate mutants (flaA, flaB, and flaG) onto the cell monolayers did not increase adherence, whereas centrifugation of the aflagellate mutants (flaH, flaJ, and flaA flaB) increased adherence slightly. We conclude that maximum adherence of A. caviae to human epithelial cells in vitro requires motility and optimal flagellar function.

scholarly journals Characterization of the Vaccinia Virus A35R Protein and Its Role in Virulence

2006 ◽  
Vol 80 (1) ◽  
pp. 306-313 ◽  
Author(s):  
Rachel L. Roper
Keyword(s):  
Vaccinia Virus ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Normal Growth ◽  
Protein Band ◽  
Mutant Virus ◽  
Translation System ◽  
Wild Type ◽  
Infected Cells

ABSTRACT The vaccinia virus A35R gene is highly conserved among poxviruses and encodes a previously uncharacterized hydrophobic acidic protein. Western blotting with anti-A35R peptide antibodies indicated that the protein is expressed early in infection and resolved as a single sharp band of ∼23 kDa, slightly higher than the 20 kDa predicted from its sequence. The protein band appeared to be the same molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, whether expressed in an in vitro transcription/translation system without microsomes or expressed in infected cells, suggesting that it was not glycosylated. A mutant virus with the A35R gene deleted (vA35Δ) formed wild-type-sized plaques on all cell lines tested (human, monkey, mouse, and rabbit); thus, A35R is not required for replication and does not appear to be a host range gene. Although the A35R protein is hydrophobic, it is unlikely to be an integral membrane protein, as it partitioned to the aqueous phase during TX-114 partitioning. The protein could not be detected in virus-infected cell supernatants. A35R localized intracellularly to the virus factories, where the first stages of morphogenesis occur. The vA35Δ mutant formed near-normal levels of the various morphogenic stages of infectious virus particles and supported normal acid-induced fusion of virus-infected cells. Despite normal growth and morphogenesis in vitro, the vA35Δ mutant virus was attenuated in intranasal challenge of mice compared to wild-type and A35R rescue virus. Thus, the intracellular A35R protein plays a role in virulence. The A35R has little homology to any protein outside of poxviruses, suggesting a novel virulence mechanism.

scholarly journals EFFECT OF ETHYL PENTANOATE ON ANTI- QUORUM ACTIVITY OF EXTRACELLULAR PROTEIN SECRETED BY BACILLUS SUBTILIS ATCC11774

2020 ◽  
Vol 5 (5) ◽  
pp. 103-112
Author(s):  
Nabilah Alhadi ◽  
Nur Anis Ayunni Khalid ◽  
HairulShahril Muhamad ◽  
Maryam Rehan ◽  
Salina Mat Radzi ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cell Communication ◽  
Inhibition Zone ◽  
Protein Band ◽  
Extracellular Protein ◽  
Bacterial Cells ◽  
Bacterial Quorum Sensing ◽  
Bacterial Quorum

Antimicrobials agents at low concentration could stress out bacteria by inducing proteins production via regulating the transcription and translation process. The interruption of bacterial quorum sensing (QS), or cell-to-cell communication is known to have the potential to weaken the bacterial pathogenicity by inhibiting their communication. This study aims to explore the potential of synthetic antimicrobial compound, ethyl pentanoate in stimulating proteins production by Bacillus subtilis ATCC11774 as well as to determine the anti-QS activity of microbial proteins produced. The bacterial cells were exposed to 0.01 MIC of ethyl pentanoate in fermentation process at 37°C for 48 h and 72 h respectively. The proteins produced were further isolated and analyzed by using Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). Results showed that a new extracellular protein with approximate size of 15 kDa was produced by B. subtilis ATCC11774 after being treated with ethyl pentanoate at 37°C for 48 h and 72h. Despites of new protein band production, there was a deletion of protein band with approximate size of 18 kDa on protein synthesized at 72 h of fermentation. Whilst, the anti-QS activity of microbial proteins produced by B. subtilis at 37°C for 48 h and 72 h was determined by agar- wells diffusion assay, resulting “halo” inhibition zone ranged from 10.00 ± 1.00 to 10.33 ± 0.56 in diameter. Therefore, B. subtilis ATCC11774 in the presence of ethyl pentanoate at 0.01 MIC could regulate the extracellular protein production and expression. The isolated protein also exhibited anti-QS activity.

scholarly journals Identification of Bacteriocin-Like Inhibitors from Rumen Streptococcus spp. and Isolation and Characterization of Bovicin 255

2001 ◽  
Vol 67 (2) ◽  
pp. 569-574 ◽  
Author(s):  
M. F. Whitford ◽  
M. A. McPherson ◽  
R. J. Forster ◽  
R. M. Teather
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Reversed Phase ◽  
Bacterial Cells ◽  
Inhibitory Peptide ◽  
Gene Encoding ◽  
Antibacterial Compounds ◽  
Streptococcus Gallolyticus ◽  
Isolation And Characterization

ABSTRACT Streptococci obtained from rumen sources were tested for the production of antibacterial compounds using a deferred-antagonism plating assay. Of 35 isolates tested, 7 were identified that inhibited the growth of other streptococci. None of the inhibitory activity was due to bacteriophage. Three isolates, LRC0253, LRC0255, and LRC0476, were selected for further characterization. Analysis of 16S ribosomal DNA indicated that LRC0476 was a strain of Streptococcus bovis, while isolates LRC0253 and LRC0255 are likely strains ofStreptococcus gallolyticus. The antibacterial compounds produced by these bacteria were protease sensitive, remained active in a pH range from 1 to 12, and did not lose activity after heating at 100°C for 15 min. The inhibitory peptide from strain LRC0255 was purified using pH-dependent adsorption and desorption to bacterial cells, followed by ammonium sulfate precipitation and reversed-phase chromatography and gel filtration. The peptide was 6 kDa, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. An oligonucleotide probe based on the N-terminal sequence of the purified peptide was used to identify the gene encoding the inhibitory peptide. The antibacterial peptide has characteristics that are very similar to those described for class II bacteriocins of gram-positive bacteria.

scholarly journals Rhamnolipid-Induced Removal of Lipopolysaccharide from Pseudomonas aeruginosa: Effect on Cell Surface Properties and Interaction with Hydrophobic Substrates

2000 ◽  
Vol 66 (8) ◽  
pp. 3262-3268 ◽  
Author(s):  
Ragheb A. Al-Tahhan ◽  
Todd R. Sandrin ◽  
Adria A. Bodour ◽  
Raina M. Maier
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Surface ◽  
Structural Changes ◽  
Fatty Acid Content ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cell Surface Hydrophobicity ◽  
Bacterial Cells ◽  
Low Levels ◽  
Rhamnolipid Biosurfactant

ABSTRACT Little is known about the interaction of biosurfactants with bacterial cells. Recent work in the area of biodegradation suggests that there are two mechanisms by which biosurfactants enhance the biodegradation of slightly soluble organic compounds. First, biosurfactants can solubilize hydrophobic compounds within micelle structures, effectively increasing the apparent aqueous solubility of the organic compound and its availability for uptake by a cell. Second, biosurfactants can cause the cell surface to become more hydrophobic, thereby increasing the association of the cell with the slightly soluble substrate. Since the second mechanism requires very low levels of added biosurfactant, it is the more intriguing of the two mechanisms from the perspective of enhancing the biodegradation process. This is because, in practical terms, addition of low levels of biosurfactants will be more cost-effective for bioremediation. To successfully optimize the use of biosurfactants in the bioremediation process, their effect on cell surfaces must be understood. We report here that rhamnolipid biosurfactant causes the cell surface ofPseudomonas spp. to become hydrophobic through release of lipopolysaccharide (LPS). In this study, two Pseudomonas aeruginosa strains were grown on glucose and hexadecane to investigate the chemical and structural changes that occur in the presence of a rhamnolipid biosurfactant. Results showed that rhamnolipids caused an overall loss in cellular fatty acid content. Loss of fatty acids was due to release of LPS from the outer membrane, as demonstrated by 2-keto-3-deoxyoctonic acid and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and further confirmed by scanning electron microscopy. The amount of LPS loss was found to be dependent on rhamnolipid concentration, but significant loss occurred even at concentrations less than the critical micelle concentration. We conclude that rhamnolipid-induced LPS release is the probable mechanism of enhanced cell surface hydrophobicity.

Polyacrylamide gel electrophoresis of Bacteroides succinogenes

1984 ◽  
Vol 30 (6) ◽  
pp. 863-866 ◽  
Author(s):  
R. Begbie ◽  
C. S. Stewart
Keyword(s):  
Gel Electrophoresis ◽  
Type Strain ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Cellulolytic Bacterium ◽  
Bacterial Cells ◽  
Polypeptide Patterns ◽  
Sds Page ◽  
Polypeptide Band

Polyacrylamide gel electrophoresis (PAGE) of sodium dodecyl sulphate (SDS) extracts of bacterial cells was used to assess the similarity of polypeptide patterns in 15 isolates of the rumen cellulolytic bacterium Bacteroides succinogenes. Analysis of densitometer traces of the polypeptide band patterns suggested that the majority of the isolates tested were closely related to the type strain S85. Representatives of other species of Gram-negative rumen bacteria had distinct SDS–PAGE patterns, and it is concluded that SDS–PAGE is a useful aid to the identification of B. succinogenes.

scholarly journals Purification and properties of an alginate lyase from a marine bacterium

1976 ◽  
Vol 159 (3) ◽  
pp. 707-713 ◽  
Author(s):  
I W Davidson ◽  
I W Sutherland ◽  
C J Lawson
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Alginate Lyase ◽  
Kinetic Studies ◽  
Defined Medium ◽  
Exchange Chromatography ◽  
Bacterial Cells ◽  
Purification And Properties ◽  
Primary Composition

An unidentified pseudomonad isolated by enrichment procedures from decomposing seaweed was grown in defined medium containing sodium alginate as the sole carbon source. The alginate lyase recovered from disrupted bacterial cells was purified by a procedure of (NH4)2SO4 precipitation, gel filtration and ion-exchange chromatography. From sodium dodecyl sulphate/polyacrylamide-gel-electrophoresis experiments a mol.wt. of about 50 000 was determined. The enzyme was active against both algal and bacterial alginate preparations. Kinetic studies together with analysis of the unsaturated oligouronide products of alginate lyase action indicated the enzyme was specific for guluronic acid-containing regions of the macromolecular substrate. The specificity of the enzyme can be used to give information about the primary composition of alginate samples.

scholarly journals Evaluation of the Potential Role of Bacillus altitudinis MT422188 in Nickel Bioremediation from Contaminated Industrial Effluents

2021 ◽  
Vol 13 (13) ◽  
pp. 7353
Author(s):  
Zarka Babar ◽  
Maryam Khan ◽  
Ghayoor Abbas Chotana ◽  
Ghulam Murtaza ◽  
Saba Shamim
Keyword(s):  
Growth Parameters ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Industrial Effluents ◽  
Heavy Metal Resistance ◽  
Pilot Scale ◽  
Metal Resistance ◽  
Bacterial Cells ◽  
Bacillus Altitudinis

The incessant pervasiveness of heavy metals in the environment is one of the precursory factors of pollution. This research study was endeavored upon to investigate the bioremediation potential of a nickel (Ni)-resistant bacterial isolate, identified as Bacillus altitudinis MT422188, whose optimum growth parameters were demonstrated at pH 7, temperature 32 °C, and 1 mM phosphate. Minimal Inhibitory Concentration (MIC) and EC50 for Ni were observed to be 20 and 11.5 mM, respectively, whereas the cross heavy-metal resistance was discerned as Cu2+ (25 mM) > Zn2+ (15 mM) > Cr6+ (10 mM) > Pb2+ (5 mM) > Co2+ (8 mM) > Cd2+ (3 mM) > Hg2+ (0 mM). Ni biosorption studies by live and heat-killed bacterial cells were suggestive of Ni uptake being facilitated by an ATP-independent efflux system. A pilot-scale study displayed the effective removal of Ni (70 mg/L and 85 mg/L) at 4- and 8-day intervals, respectively. Moreover, chemotaxis and motility assays indicated the role of Ni as a chemoattractant for bacterial cells. The presence of Ni reduced the GR (0.001 ± 0.003 Ug−1FW), POX (0.001 ± 0.001 Ug−1FW), and SOD (0.091 ± 0.003 Ug−1FW) activity, whereas Sodium dodecyl sulphate—Polyacrylamide gel electrophoresis (SDS-PAGE) revealed the presence of metallothionein (60 kDa). Kinetic and isotherm studies suggested a pseudo second-order and Freundlich model to be better fitted for our study. The thermodynamic parameters (∆H° = 3.0436 kJ/mol, ∆S° = 0.0224 kJ/mol/K) suggested the process to be endothermic, spontaneous, and favorable in nature. FTIR analysis elucidated the interaction of hydroxyl and carboxyl groups with Ni. Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS) demonstrated changes in the morphological and elemental composition of the bacterial cells, which affirmed their interaction with Ni during biosorption. In summary, our study concludes the efficient role of Bacillus altitudinis MT422188 in removing Ni from polluted industrial effluents.

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