scholarly journals INFLUENCE OF PEPTIDE P34 ON GENE EXPRESSION OF LISTERIA MONOCYTOGENES AND LISTERIA SEELEGERI

2016 ◽  
Vol 9 (1) ◽  
pp. 116
Author(s):  
Rodrigo De Almeida Vaucher ◽  
Janice Luehring Giongo ◽  
Magton Estivales ◽  
Virgínia Cielo Rech ◽  
Vivian Shinobu Kishimoto Nishihira ◽  
...  
Keyword(s):  
Gene Expression ◽  
Listeria Monocytogenes ◽  
Cell Surface ◽  
Membrane Structure ◽  
Brain Heart Infusion ◽  
Expression Of Genes ◽  
Inhibition Zones ◽  
Listeria Seeligeri ◽  
Similar Decrease ◽  
Infusion Agar

<p><strong>Objective: </strong>Investigate the influence of the antimicrobial peptides P34 and nisin on the expression of genes associated with components of the cell surface of <em>Listeria monocytogenes</em> and <em>Listeria seeligeri</em>.</p><p><strong>Methods: </strong>Antimicrobial activity was determined by addition of peptide P34 and nisin (12.5 µg/ml) onto Brain Heart Infusion agar (BHI) plates previously inoculated with indicator strains (<em>L. monocytogenes</em> ATCC 7644 or <em>L. seeligeri </em>AC 82/4) after incubation for 24 h at 37 °C or 240 h at 4 °C. Ribonucleic acid (RNA) was directly extracted from bacterial colonies at the border of the inhibition zones, and the expression levels of genes D-alanine-D-alanyl carrier protein ligase<em> (dltA), </em>putative phospholipid lysinylation<em> </em>(<em>Imo 1695</em>)<em> </em>and EIIAB<sup>Man</sup> of mannose-specific PTS<em> </em>(<em>mptA</em>) were determined using real-time PCR.</p><p><strong>Results</strong><strong>: </strong>A non-significant increase in the levels of transcription of genes <em>dltA, Imo1695 </em>and<em> mptA</em> was observed for <em>L. monocytogenes </em>treated with peptide P34 or nisin. Both peptides caused a similar decrease in <em>dltA</em> gene expression in <em>L. seeligeri</em>. The expression of gene <em>Imo1695</em> significantly decreased (about 2000-fold) after treatment with the peptide P34 at 37 °C, while at 4 °C a reduction of 12-fold and 5-fold was detected for P34 and nisin, respectively. A significant decrease in <em>mptA</em> gene expression was observed by exposition to peptide P34 (31.872-fold) and nisin (16.047-fold) for 24 h at 37 °C.</p><p><strong>Conclusion: </strong>The results suggest that both peptide P34 and nisin influence the expression of genes related with the cell-surface/cell-membrane structure of <em>L. seeligeri</em> and in lesser extent <em>L. monocytogenes</em>.</p>

Inactivation of Listeria monocytogenes Scott A 49594 in Apple Juice Supplemented with Cinnamon

2002 ◽  
Vol 65 (10) ◽  
pp. 1663-1666 ◽  
Author(s):  
J. YUSTE ◽  
D. Y. C. FUNG
Keyword(s):  
Listeria Monocytogenes ◽  
Apple Juice ◽  
Brain Heart Infusion ◽  
Killing Effect ◽  
Brain Heart Infusion Agar ◽  
Agar Layer ◽  
Infusion Agar ◽  
Enrichment Step

Normal (pH 3.7) and adjusted (pH 5.0) pasteurized apple juice containing cinnamon (0, 0.1, 0.2, and 0.3%) was inoculated with Listeria monocytogenes Scott A 49594 at 104 CFU/ml and stored at 5 and 20°C for 7 days. Counts on tryptic soy agar (TSA), modified Oxford (MOX) medium, and thin agar layer (TAL) were determined at 1 h and 1, 3, and 7 days. The TAL method (MOX medium overlaid with TSA) was used for the recovery of injured cells. In apple juice, both at normal and adjusted pH, with any doses of cinnamon, no L. monocytogenes (a 4.6-log CFU/ml reduction) was detected after 1 h of storage at both temperatures, and no growth occurred at any points of storage. Therefore, cinnamon by itself (regardless of pH) had a pronounced killing effect. A further enrichment step with brain heart infusion agar showed that L. monocytogenes was completely inactivated in apple juice stored at 20°C, except in pH 5.0 samples with 0.1% of cinnamon. The TAL method was as effective as TSA in recovering injured cells of L. monocytogenes. Cinnamon considerably inactivates L. monocytogenes in apple juice and thus enhances the safety of this product.

Unstable Expression and Thermal Instability of a Species-Specific Cell Surface Epitope Associated with a 66-Kilodalton Antigen Recognized by Monoclonal Antibody EM-7G1 within Serotypes of Listeria monocytogenes Grown in Nonselective and Selective Broths

1998 ◽  
Vol 64 (8) ◽  
pp. 3070-3074 ◽  
Author(s):  
Ramakrishna Nannapaneni ◽  
Robert Story ◽  
Arun K. Bhunia ◽  
Michael G. Johnson
Keyword(s):  
Monoclonal Antibody ◽  
Listeria Monocytogenes ◽  
Cell Surface ◽  
Brain Heart Infusion ◽  
Live Cells ◽  
Enzyme Linked Immunosorbent Assay ◽  
Specific Cell ◽  
Enrichment Broth ◽  
Species Specific ◽  
Heat Instability

ABSTRACT Conditions that resulted in unstable expression and heat instability of a cell surface epitope associated with a 66-kDa antigen in Listeria monocytogenes serotypes were identified with the probe monoclonal antibody (MAb) EM-7G1 in an enzyme-linked immunosorbent assay. This epitope appeared to be absent in three serotypes (serotypes 3b, 4a, and 4c), which did not react with MAb EM-7G1 irrespective of the enrichment broth tested. The remaining 10 serotypes were detected by MAb EM-7G1 only when cells were grown in nonselective brain heart infusion broth (BHI) or selectiveListeria enrichment broth (LEB). When cells were grown inListeria repair broth (LRB), only 6 of the 13 serotypes were detected by MAb EM-7G1, and recognition of serogroup 4 was completely lost. None of the 13 serotypes was detected by MAb EM-7G1 when cells were grown in two other commonly usedListeria-selective media, UVM1 broth and Fraser broth (FRB), indicating that possible loss of epitope expression occurred under these conditions. MAb EM-7G1 maintained species specificity without cross-reacting with live or heat-killed cells of six otherListeria spp. (Listeria ivanovii,Listeria innocua, Listeria seeligeri,Listeria welshimeri, Listeria grayi, andListeria murrayi) irrespective of the enrichment conditions tested. Due to heat instability of the cell surface epitope when it was exposed to 80 or 100°C for 20 min, MAb EM-7G1 is suitable for detection of live cells of L. monocytogenes in BHI or LEB but not in LRB, UVM1, or FRB enrichment medium.

Global Gene Expression of Listeria monocytogenes to Salt Stress

2012 ◽  
Vol 75 (5) ◽  
pp. 906-912 ◽  
Author(s):  
DONGRYEOUL BAE ◽  
CONNIE LIU ◽  
TING ZHANG ◽  
MARCUS JONES ◽  
SCOTT N. PETERSON ◽  
...  
Keyword(s):  
Gene Expression ◽  
Salt Stress ◽  
Listeria Monocytogenes ◽  
Cell Growth ◽  
Expression Profiles ◽  
Brain Heart Infusion ◽  
Global Gene Expression ◽  
Phosphotransferase System ◽  
Transcript Levels ◽  
Qrt Pcr

Outbreaks of listeriosis caused by the ingestion of Listeria-contaminated ready-to-eat foods have been reported worldwide. Many ready-to-eat foods, such as deli meat products, contain high amounts of salt, which can disrupt the maintenance of osmotic balance within bacterial cells. To understand how Listeria monocytogenes adapts to salt stress, we examined the growth and global gene expression profiles of L. monocytogenes strain F2365 under salt stress using oligonucleotide probe-based DNA array and quantitative real-time PCR (qRT-PCR) analyses. The growth of L. monocytogenes in brain heart infusion (BHI) medium with various concentrations of NaCl (2.5, 5, and 10%) was significantly inhibited (P &lt; 0.01) when compared with growth in BHI with no NaCl supplementation. Microarray data indicated that growth in BHI medium with 1.2% NaCl upregulated 4 genes and down-regulated 24 genes in L. monocytogenes, which was confirmed by qRT-PCR. The transcript levels of genes involved in the uptake of glycine betaine/l-proline were increased, whereas genes associated with a putative phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS), metabolic enzymes, and virulence factor were down-regulated. Specifically, the expression levels of PTS transport genes were shown to be dependent on NaCl concentration. To further examine whether the down-regulation of PTS genes is related to decreased cell growth, the transcript levels of genes encoding components of enzyme II, involved in the uptake of various sugars used as the primary carbon source in bacteria, were also measured using qRT-PCR. Our results suggest that the decreased transcript levels of PTS genes may be caused by salt stress or reduced cell growth through salt stress. Here, we report global transcriptional profiles of L. monocytogenes in response to salt stress, contributing to an improved understanding of osmotolerance in this bacterium.

Inactivation of Listeria monocytogenes Scott A on Artificially Contaminated Frankfurters by High-Pressure Processing

2000 ◽  
Vol 63 (5) ◽  
pp. 662-664 ◽  
Author(s):  
L. A. LUCORE ◽  
T. H. SHELLHAMMER ◽  
A. E. YOUSEF
Keyword(s):  
High Pressure ◽  
Listeria Monocytogenes ◽  
Foodborne Pathogens ◽  
Bacterial Population ◽  
Brain Heart Infusion ◽  
High Pressure Processing ◽  
Brain Heart Infusion Agar ◽  
Log Reduction ◽  
Viable Method ◽  
Infusion Agar

Vacuum-packaged frankfurters, inoculated with 24-h cultures of Listeria monocytogenes Scott A (∼109 CFU/ml) by injection into the packages, were held at pressures of 300, 500, and 700 MPa for up to 9 min. L. monocytogenes were washed from the surface of the frankfurter and plated onto brain heart infusion agar. During the time to achieve 300, 500, and 700 MPa (come-up time), L. monocytogenes populations decreased by 1, &gt;3, and &gt;5 logs, respectively. Additional inactivation of L. monocytogenes occurred while the samples were held at 300 and 500 MPa. A 5-log reduction in bacterial population was possible at all pressure treatments; however, pressurization at 700 MPa showed the fastest inactivation with L. monocytogenes reduced from 108 to 102 CFU/package during the come-up time. These results show that high-pressure processing may be a viable method for controlling foodborne pathogens in postprocessed, packaged frankfurters.

scholarly journals ANTIBACTERIAL ACTIVITY OF CELERY LEAVES (APIUM GRAVEOLENS L.) FORMULATED IN TOOTHPASTE AGAINST STREPTOCOCCUS MUTANS

2019 ◽  
pp. 14-16
Author(s):  
ERZA GENATRIKA ◽  
FITA SATRIANI ◽  
INDRI HAPSARI
Keyword(s):  
Antibacterial Activity ◽  
Brain Heart Infusion ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Apium Graveolens ◽  
Diffusion Method ◽  
Activity Test ◽  
Maximum Inhibition ◽  
Inhibition Zones ◽  
Infusion Agar

Objective: The objective of this research was to determine the antibacterial activity of the toothpaste from an extract of celery leaves on Streptococcusmutans.Methods: The toothpaste was formulated with various concentrations of celery leaves, F1 with concentration of extract (6.25%), F2 (12.5%), andF3 (25%). Each formula was tested the physical characteristics and antibacterial activity toward S. mutans. The antibacterial activity was determinedby the agar well diffusion method using brain heart infusion agar plates. Furthermore, the antibacterial activities were assessed by the presence orabsence of inhibition zones after the plates were incubated at 37°C for 24 h.Results: The results from this test illustrate that all toothpastes under study at various concentrations of celery leaves extract exhibited antibacterialactivity. Maximum inhibition zone in antibacterial activity test was shown by F2 (12.5%). Therefore, we can use these toothpastes as naturalantibacterial on prevention of dental caries caused S. mutans.Conclusion: The toothpaste from an extract of celery leaves showed significant antibacterial activity against S. mutans.

scholarly journals Microbiological Evaluation of Elastomeric Chains

2007 ◽  
Vol 77 (5) ◽  
pp. 890-893 ◽  
Author(s):  
Giovana Rembowski Casaccia ◽  
Janaína C. Gomes ◽  
Daniela Sales Alviano ◽  
Antonio Carlos de Oliveira Ruellas ◽  
Eduardo Franzotti Sant' Anna
Keyword(s):  
Antimicrobial Agents ◽  
Brain Heart Infusion ◽  
Inhibitory Effect ◽  
Pathogenic Microorganisms ◽  
Inhibition Zones ◽  
The Moment ◽  
Careful Manipulation ◽  
Elastomeric Chains ◽  
Infusion Agar

Abstract Objectives: To evaluate in vitro the surface of elastomeric chains of different manufacturers to verify the presence of pathogenic microorganisms at the moment of unpacking and analyze a possible inhibitory effect of the elastomeric chain when exposed to microorganisms of the oral cavity, for example, Streptococcus mutans, Lactobacillus casei, and Candida albicans. Materials and Methods: Elastomeric chains from Ortho-Organizers Inc, 3M Unitek, and Dental Morelli were placed in petri plates with brain heart infusion agar medium and in sterile test tubes with brain heart infusion broth. The samples were incubated at 37°C and analyzed at 24 hours, 48 hours, 3 days, and 7 days. In addition, elastomeric chains from the three manufacturers were placed in dishes, inoculated with microorganisms, incubated at 37°C, and analyzed after 24 and 72 hours. Results: No microorganism growth was detected after all incubation periods. No inhibition zones were identified surrounding the elastomeric chain. Conclusions: The results suggest that the fabrication of elastomeric chain is in accordance with biohazard concepts. However, careful manipulation is necessary to avoid colonization of pathogenic microorganisms since the composition of the elastomeric chains analyzed do not include antimicrobial agents.

scholarly journals ANTIMICROBIAL PEPTIDE P34 INFLUENCES GENE EXPRESSION OF LISTERIA MONOCYTOGENES GROWING IN SOFT CHEESE

2016 ◽  
Vol 8 (11) ◽  
pp. 235 ◽  
Author(s):  
Rodrigo De Almeida Vaucher ◽  
Janice Luehring Giongo ◽  
VÍrginia Cielo Rech ◽  
Roberto Christ Vianna Santos ◽  
Leonardo Quintana S. Lopes ◽  
...  
Keyword(s):  
Gene Expression ◽  
Listeria Monocytogenes ◽  
Antimicrobial Peptide ◽  
Real Time ◽  
Specific Gene ◽  
Antimicrobial Substances ◽  
Expression Of Genes ◽  
Diffusion Technique ◽  
Soft Cheese ◽  
Culture Supernatants

Objective: To evaluate whether antimicrobial substances produced by autochthonous lactic acid bacteria (LAB) from Minas Frescal cheese are able to enhance the activity of bacteriocin P34 against Listeria monocytogenes and investigate the influence of P34 in specific gene expression of this bacterium after the inoculation in Minas Frescal cheese.Methods: Bacillus sp. P34 and L. monocytogenes ATCC 7644 were used in this study. The antimicrobial peptide P34 was purified and applied (0, 800 or 6400 AU/ml) to cheese surface before inoculation with L. monocytogenes. Antimicrobial activity and synergism were detected using the agar diffusion technique. Expression levels of D-Alanine-D-alanyl carrier protein ligase (dltA), Putative phospholipid lysinylation (Imo 1695) and EIIABMan of mannose-specific PTS (mptA) mRNAs in bacteriocin-treated L. monocytogenes growing in Minas Frescal cheese were determined using real-time PCR.Results: The peptide P34 showed increased antilisterial activity when combined with culture supernatants of some selected LAB isolated from Minas Frescal cheese. The addition of peptide P34 to cheese caused a decrease of up to 3 log cycles in viable counts of artificially inoculated L. monocytogenes. The influence of peptide P34 on the expression of genes associated with components of the cell surface of L. monocytogenes was investigated by real-time PCR. A significant increase in the expression of the genes dltA, Imo 1695 and mptA was observed after 96 h in the presence of peptide P34.Conclusion: These results suggest that the peptide P34 influences the expression of genes involved in D-alanylation of teichoic acids and lipoteichoic acids and lysination of the cell membrane of phospholipids.

scholarly journals Impact of Environmental Stressors on Gene Expression in the Embryo of the Italian Wall Lizard

2021 ◽  
Vol 11 (11) ◽  
pp. 4723
Author(s):  
Rosaria Scudiero ◽  
Chiara Maria Motta ◽  
Palma Simoniello
Keyword(s):  
Gene Expression ◽  
Protein Interactions ◽  
Membrane Trafficking ◽  
Translational Regulation ◽  
Cellular Protection ◽  
Terrestrial Vertebrate ◽  
Expression Of Genes ◽  
Stress Changes ◽  
Probable Consequence ◽  
The Impact

The cleidoic eggs of oviparous reptiles are protected from the external environment by membranes and a parchment shell permeable to water and dissolved molecules. As a consequence, not only physical but also chemical insults can reach the developing embryos, interfering with gene expression. This review provides information on the impact of the exposure to cadmium contamination or thermal stress on gene expression during the development of Italian wall lizards of the genus Podarcis. The results obtained by transcriptomic analysis, although not exhaustive, allowed to identify some stress-reactive genes and, consequently, the molecular pathways in which these genes are involved. Cadmium-responsive genes encode proteins involved in cellular protection, metabolism and proliferation, membrane trafficking, protein interactions, neuronal transmission and plasticity, immune response, and transcription regulatory factors. Cold stress changes the expression of genes involved in transcriptional/translational regulation and chromatin remodeling and inhibits the transcription of a histone methyltransferase with the probable consequence of modifying the epigenetic control of DNA. These findings provide transcriptome-level evidence of how terrestrial vertebrate embryos cope with stress, giving a key to use in population survival and environmental change studies. A better understanding of the genes contributing to stress tolerance in vertebrates would facilitate methodologies and applications aimed at improving resistance to unfavourable environments.

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