scholarly journals A Novel Dibenzoxazepine Attenuates Intracellular Salmonella Typhimurium Oxidative Stress Resistance

2021 ◽  
Author(s):  
Cheng-Yun Hsu ◽  
Yi-Lun Wu ◽  
Hsueh-Chun Lin ◽  
Man-Yi Lin ◽  
Shih-Hsiu Chou ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Salmonella Typhimurium ◽  
Stress Resistance ◽  
Pathogenic Bacteria ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Oxidative Stress Resistance

The incidence of diseases caused by pathogenic bacteria with resistance to common antibiotics is consistently increasing. In addition, Gram-negative bacteria are particularly difficult to treat with antibiotics, especially those that can invade and proliferate intracellularly.

scholarly journals Test for the antibacterial inhibition of kaffir lime leaf (Citrus hysteric D.C) extract against pathogen bacteria in improving food safety

2021 ◽  
Vol 883 (1) ◽  
pp. 012056
Author(s):  
S J Nendissa ◽  
D M Nendissa
Keyword(s):  
Antibacterial Activity ◽  
Food Safety ◽  
Salmonella Typhimurium ◽  
Pathogenic Bacteria ◽  
Leaf Extract ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

Abstract Kafir lime leaf (Citrus hystrix) is a plant from the citrus tribe that has long been known by community as flavor ingredient. To support its use and increase its application in supporting food safety, a test the inhibition of on kaffir lime leaf extract against pathogenic bacteria, namely Gram Negative Bacteria (Escherichia coli, Salmonella typhimurium) and Gram Positive bacteria (Staphylococcus aereus, P. aeroginosa). Making kaffir lime leaf extract (Citrus hystrix) was done by weighing 150g of lime leaf powder, then immersing in 96% ethanol solution and leaving for + 3 days. Kaffir lime leaf extract was dissolved with sterile distilled aquades to obtain a concentration of 5%, 10% and 15%. The antibacterial activity of kaffir lime leaf extract was tested by diffusion method using disc paper to determine of the bacterial growth inhibition area. The results showed that kaffir lime extract had antibacterial activity inhibition of 12,78 mm of S. aereus, 9 mm of E.coli, 7,12 mm of S. typhimurium and 9,3 mm of P. aeroginosa. Kaffir lime leaf extract has inhibition effectiveness for gram positive bacteria Staphylococcus aereus and gram negative bacteria E. coli, Salmonella typhimurium, P. aeroginosa. Thus, kaffir lime leaf extract can be used as a decontaminant agait theses 4 type of bacteria, especially Staphylococcus aereus which has a strong inhibitory power, so it can maintain quality and increase the safety of mead based foods

scholarly journals Structural and functional analysis of the Francisella lysine decarboxylase as a key actor in oxidative stress resistance

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jan Felix ◽  
Claire Siebert ◽  
Julia Novion Ducassou ◽  
Jérôme Nigou ◽  
Pierre Simon Garcia ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Stress Response ◽  
Stress Resistance ◽  
Pathogenic Bacteria ◽  
Host Cells ◽  
Acid Decarboxylase ◽  
Growth Media ◽  
Lysine Decarboxylase ◽  
Oxidative Stress Resistance

AbstractFrancisella tularensis is one of the most virulent pathogenic bacteria causing the acute human respiratory disease tularemia. While the mechanisms underlying F. tularensis pathogenesis are largely unknown, previous studies have shown that a F. novicida transposon mutant with insertions in a gene coding for a putative lysine decarboxylase was attenuated in mouse spleen, suggesting a possible role of its protein product as a virulence factor. Therefore, we set out to structurally and functionally characterize the F. novicida lysine decarboxylase, which we termed LdcF. Here, we investigate the genetic environment of ldcF as well as its evolutionary relationships with other basic AAT-fold amino acid decarboxylase superfamily members, known as key actors in bacterial adaptative stress response and polyamine biosynthesis. We determine the crystal structure of LdcF and compare it with the most thoroughly studied lysine decarboxylase, E. coli LdcI. We analyze the influence of ldcF deletion on bacterial growth under different stress conditions in dedicated growth media, as well as in infected macrophages, and demonstrate its involvement in oxidative stress resistance. Finally, our mass spectrometry-based quantitative proteomic analysis enables identification of 80 proteins with expression levels significantly affected by ldcF deletion, including several DNA repair proteins potentially involved in the diminished capacity of the F. novicida mutant to deal with oxidative stress. Taken together, we uncover an important role of LdcF in F. novicida survival in host cells through participation in oxidative stress response, thereby singling out this previously uncharacterized protein as a potential drug target.

Interaction of a Free-Living Soil Nematode, Caenorhabditis elegans, with Surrogates of Foodborne Pathogenic Bacteria

2003 ◽  
Vol 66 (9) ◽  
pp. 1543-1549 ◽  
Author(s):  
GARY L. ANDERSON ◽  
KRISHAUN N. CALDWELL ◽  
LARRY R. BEUCHAT ◽  
PHILLIP L. WILLIAMS
Keyword(s):  
Caenorhabditis Elegans ◽  
Young Adult ◽  
Salmonella Typhimurium ◽  
Avirulent Strain ◽  
Soil Nematode ◽  
Gram Negative Bacteria ◽  
Nematode Caenorhabditis Elegans ◽  
Free Living ◽  
Gram Positive ◽  
Gram Negative

Free-living nematodes may harbor, protect, and disperse bacteria, including those ingested and passed in viable form in feces. These nematodes are potential vectors for human pathogens and may play a role in foodborne diseases associated with fruits and vegetables eaten raw. In this study, we evaluated the associations between a free-living soil nematode, Caenorhabditis elegans, and Escherichia coli, an avirulent strain of Salmonella Typhimurium, Listeria welshimeri, and Bacillus cereus. On an agar medium, young adult worms quickly moved toward colonies of all four bacteria; over 90% of 3-day-old adult worms entered colonies within 16 min after inoculation. After 48 h, worms moved in and out of colonies of L. welshimeri and B. cereus but remained associated with E. coli and Salmonella Typhimurium colonies for at least 96 h. Young adult worms fed on cells of the four bacteria suspended in K medium. Worms survived and reproduced with the use of nutrients derived from all test bacteria, as determined for eggs laid by second-generation worms after culturing for 96 h. Development was slightly slower for worms fed gram-positive bacteria than for worms fed gram-negative bacteria. Worms that fed for 24 h on bacterial lawns formed on tryptic soy agar dispersed bacteria over a 3-h period when they were transferred to a bacteria-free agar surface. The results of this study suggest that C. elegans and perhaps other free-living nematodes are potential vectors for both gram-positive and gram-negative bacteria, including foodborne pathogens in soil.

scholarly journals Role of rgsA in Oxidative Stress Resistance in Pseudomonas aeruginosa

2021 ◽  
Author(s):  
Shuyi Hou ◽  
Jiaqin Zhang ◽  
Xiaobo Ma ◽  
Qiang Hong ◽  
Lili Fang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pseudomonas Aeruginosa ◽  
Stress Resistance ◽  
Oxidative Stress Resistance

Effectiveness of Trisodium Phosphate, Acidified Sodium Chlorite, Citric Acid, and Peroxyacids against Pathogenic Bacteria on Poultry during Refrigerated Storage

2007 ◽  
Vol 70 (9) ◽  
pp. 2063-2071 ◽  
Author(s):  
ELENA del RÍO ◽  
REBECA MURIENTE ◽  
MIGUEL PRIETO ◽  
CARLOS ALONSO-CALLEJA ◽  
ROSA CAPITA
Keyword(s):  
Citric Acid ◽  
Salmonella Enteritidis ◽  
Pathogenic Bacteria ◽  
Trisodium Phosphate ◽  
Sodium Chlorite ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Microbial Group ◽  
And Control

The effects of dipping treatments (15 min) in potable water or in solutions (wt/vol) of 12% trisodium phosphate (TSP), 1,200 ppm acidified sodium chlorite (ASC), 2% citric acid (CA), and 220 ppm peroxyacids (PA) on inoculated pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Salmonella Enteritidis, Escherichia coli, and Yersinia enterocolitica) and skin pH were investigated throughout storage of chicken legs (days 0, 1, 3, and 5) at 3 ± 1°C. All chemical solutions reduced microbial populations (P < 0.001) as compared with the control (untreated) samples. Similar bacterial loads (P > 0.05) were observed on water-dipped and control legs. Type of treatment, microbial group, and sampling day influenced microbial counts (P < 0.001). Average reductions with regard to control samples were 0.28 to 2.41 log CFU/g with TSP, 0.33 to 3.15 log CFU/g with ASC, 0.82 to 1.97 log CFU/g with CA, and 0.07 to 0.96 log CFU/g with PA. Average reductions were lower (P < 0.001) for gram-positive (0.96 log CFU/g) than for gram-negative (1.33 log CFU/g) bacteria. CA and ASC were the most effective antimicrobial compounds against gram-positive and gram-negative bacteria, respectively. TSP was the second most effective compound for both bacterial groups. Average microbial reductions per gram of skin were 0.87 log CFU/g with TSP, 0.86 log CFU/g with ASC, 1.39 log CFU/g with CA, and 0.74 log CFU/g with PA for gram-positive bacteria, and 1.28 log CFU/g with TSP, 2.03 log CFU/g with ASC, 1.23 log CFU/g with CA, and 0.78 log CFU/g with PA for gram-negative bacteria. With only a few exceptions, microbial reductions in TSP- and ASC-treated samples decreased and those in samples treated with CA increased throughout storage. Samples treated with TSP and samples dipped in CA and ASC had the highest and lowest pH values, respectively, after treatment. The pH of the treated legs tended to return to normal (6.3 to 6.6) during storage. However, at the end of storage, the pH of legs treated with TSP remained higher and that of legs treated with CA remained lower than normal.

scholarly journals Antimicrobial Activity of Gardenia jasminoides Callus and Crude Leaf Extracts for some Organic Solvents against some Pathogenic Bacteria and Yeasts

2014 ◽  
Vol 8 (3) ◽  
pp. 40-45
Author(s):  
Zina Hashem Shehab ◽  
Huda Suhail Abid ◽  
Sumaya Fadhil Hamad ◽  
Sara Haitham
Keyword(s):  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Pathogenic Bacteria ◽  
Saccharomyces Boulardii ◽  
Gram Negative Bacteria ◽  
Proteus Vulgaris ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Gardenia Jasminoides

The study was conducted to evaluate the inhibitory activity of methanol extract of Gardenia jasminoides leaves compared with leaf crude extracts for some organic solvents namely Methanol, Ethanol, Petroleum ether, Asetone and Chloroform on growth of some pathogenic bacteria and yeast, which included four gram positive isolates Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes and Bacillus cereus and gram negative isolates Escherichia coli, Salmonella typhi, Proteus vulgaris and Pseudomonas aeruginosa and some yeasts Candida albicans and Saccharomyces boulardii, by using well diffusion method. The inhibitory activity of extracts in the tested bacterial strains and yeasts was varied according to the type of extracting solvents and are tested microorganisms. The methanol callus extract which grown on Murashige and Skoog (MS) media by using (Naphthalen acitic acid) NAA and (Benzyle adenine) BA as growth regulator highly effective as compared to the other extracts as for inhibition of three gram positive bacteria and three gram negative bacteria,which include Staphylococcus aureus and, Proteus vulgaris, followed by acetone and ethanolic extracts which include two gram positive bacteria and two gram negative bacteria. All extracts had highly effect in growth of Candida albicans while all crude extracts didn’t show any sensitivity against Saccharomyces boulardii, and when we’d done (High Performance Liquid Chromatography) HPLC test for detection of some active compound we found Quinic acid, Iridiods glycosides and Crocin which its rate in fresh callus was higher than fresh leaves.

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