scholarly journals Propanediol oxidoreductases of Escherichia coli, Klebsiella pneumoniae and Salmonella typhimurium. Aspects of interspecies structural and regulatory differentiation

1985 ◽  
Vol 231 (1) ◽  
pp. 145-149 ◽  
Author(s):  
J Ros ◽  
J Aguilar
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Klebsiella Pneumoniae ◽  
Salmonella Typhimurium ◽  
Peptide Mapping ◽  
Considerable Extent ◽  
Anaerobic Conditions ◽  
Aerobic Conditions ◽  
One Dimensional ◽  
E Coli

The enzyme propanediol oxidoreductase, which converts the lactaldehyde formed in the metabolism of fucose and rhamnose into propane-1,2-diol under anaerobic conditions, was investigated in Escherichia coli, Klebsiella pneumoniae and Salmonella typhimurium. Structural analysis indicated that the enzymes of E. coli and K. pneumoniae have the same Mr and pI, whereas that of Salm. typhimurium also has the same Mr but a slightly different pI. One-dimensional peptide mapping showed identity between the E. coli and K. pneumoniae enzymes when digested with α-chymotrypsin, Staphylococcus aureus V8 proteinase or subtilisin. In the case of Salm. typhimurium, this held only for the subtilisin-digested enzymes, indicating that the hydrophobic regions were preserved to a considerable extent. Anaerobically, the three species induced an active propanediol oxidoreductase when grown on fucose or rhamnose. An inactive propanediol oxidoreductase was induced in Salm. typhimurium by either fucose or rhamnose under aerobic conditions, and this was activated once anaerobiosis was established. An inactive propanediol oxidoreductase was also induced in E. coli under aerobic conditions, but only by growth on fucose. The inactive enzyme was not induced by either of the sugars in K. pneumoniae.

scholarly journals ATIVIDADE ANTIMICROBIANA DE MICRORGANISMOS ISOLADOS DE GRÃOS DE KEFIR

2018 ◽  
Vol 19 (0) ◽  
Author(s):  
Priscila Alves Dias ◽  
Daiani Teixeira Silva ◽  
Cláudio Dias Timm
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Listeria Monocytogenes ◽  
Salmonella Typhimurium ◽  
Salmonella Enterica ◽  
Escherichia Coli O157 ◽  
E Coli

Resumo Kefir é o produto da fermentação do leite pelos grãos de kefir. Esses grãos contêm uma mistura simbiótica de bactérias e leveduras imersas em uma matriz composta de polissacarídeos e proteínas. Muitos benefícios à saúde humana têm sido atribuídos ao kefir, incluindo atividade antimicrobiana contra bactérias Gram positivas e Gram negativas. A atividade antimicrobiana de 60 microrganismos isolados de grãos de kefir, frente à Escherichia coli O157:H7, Salmonella enterica subsp. enterica sorotipos Typhimurium e Enteritidis, Staphylococcus aureus e Listeria monocytogenes, foi estudada através do teste do antagonismo. A ação antimicrobiana dos sobrenadantes das bactérias ácido-lácticas que apresentaram atividade no teste do antagonismo foi testada. O experimento foi repetido usando sobrenadantes com pH neutralizado. Salmonella Typhimurium e Enteritidis sobreviveram por 24 horas no kefir em fermentação. E. coli O157:H7, S. aureus e L. monocytogenes foram recuperados até 72 horas após o início da fermentação. Todos os isolados apresentaram atividade antimicrobiana contra pelo menos um dos patógenos usados no teste do antagonismo. Sobrenadantes de 25 isolados apresentaram atividade inibitória e três mantiveram essa atividade com pH neutralizado. As bactérias patogênicas estudadas sobreviveram por tempo superior àquele normalmente utilizado para a fermentação do kefir artesanal, o que caracteriza perigo em potencial para o consumidor quando a matéria-prima não apresentar segurança sanitária. Lactobacillus isolados de grãos de kefir apresentam atividade antimicrobiana contra cepas de E. coli O157:H7, Salmonella sorotipos Typhimurium e Enteritidis, S. aureus e L. monocytogenes além daquela exercida pela diminuição do pH.

Antimicrobial Effects of Novel H2O2-Ag+ Complex on Membrane Damage to Staphylococcus aureus,Escherichia coli and Salmonella typhimurium

2021 ◽  
Author(s):  
Bing Han ◽  
Xiaoyu Han ◽  
Mengmeng Ren ◽  
Yilin You ◽  
Jicheng Zhan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Hydrogen Peroxide ◽  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Membrane Damage ◽  
Bactericidal Effect ◽  
E Coli ◽  
Bacterial Cell Membrane ◽  
Time Kill ◽  
Environmental Disinfection

Diseases caused by harmful microorganisms pose a serious threat to human health. Safe and environment-friendly disinfectants are, therefore, essential in preventing and controlling such pathogens. This study aimed to investigate the antimicrobial activity and mechanism of a novel hydrogen peroxide and silver (H 2 O 2 -Ag + ) complex (HSC) in combatting Staphylococcus aureus ATCC 29213, Escherichia coli O157:H7 NCTC 12900 and Salmonella typhimurium SL 1344. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against S. aureus were found to be 0.014 % H 2 O 2 -3.125 mg/L Ag + , while 0.028 % H 2 O 2 -6.25 mg/L Ag + for both E. coli and S. typhimurium . Results of the growth curve assay and time-kill trial suggest that the HSC could inhibit the growth of the tested bacteria, as 99.9 % of viable cells were killed following treatment at the 1 MIC for 3 h. Compared with Oxytech D10 disinfectant (0.25 % H 2 O 2 -5 mg/L Ag + ), the HSC exhibited better antibacterial efficacy at a lower concentration (0.045 % H 2 O 2 -10 mg/L Ag + ). The mechanism of antibacterial action of HSC was found including the disruption of the bacterial cell membrane, followed by entry into the bacteria cell to reduce intracellular adenosine triphosphate (ATP) concentration, and inhibit the activity of antioxidases, superoxide dismutase (SOD) and catalase (CAT). The enhanced bactericidal effect of hydrogen peroxide combined with silver indicates a potential for its application in environmental disinfection, particularly in the food industry.

scholarly journals Actividad antibacteriana in vitro de aceites esenciales de diferentes especies del género Citrus

2017 ◽  
Vol 46 (2) ◽  
Author(s):  
Miladys Esther Torrenegra Alarcón ◽  
Nerlis Paola Pájaro ◽  
Glicerio León Méndez
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
Staphylococcus Epidermidis ◽  
E Coli

Se evaluó la actividad antibacteriana in vitro de aceites esenciales de diferentes especiesdel género Citrus frente a cepas ATCC de Staphylococcus aureus, Staphylococcus epidermidis,Klebsiella pneumoniae, Pseudomonas aeruginosa y Escherichia coli, determinandola concentración mínima inhibitoria (CMI) y la concentración mínima bactericida(CMB). Las bacterias se replicaron en medios de agar y caldos específicos. Se determinóel momento de máxima densidad óptica (DO620) para emplearlo como tiempode incubación; luego se hicieron pruebas de evaluación de sensibilidad con la exposiciónde las cepas a concentraciones a 1000 g/mL del extracto en caldo. Para solubilizarse empleó dimetilsulfóxido (DMSO) al 1%. Posteriormente, se le determinó laconcentración mínima inhibitoria mediante metodologías de microdilución en caldoy la concentración mínima bactericida. Encontrándose una actividad de los aceitesesenciales del género Citrus, con valores de CMI ≥ 600 mg/mL frente a S. aureus,S. epidermidis, K. pneumoniae, P. aeruginosa y E. coli. En función a los resultados obtenidos,se concluye que las diferentes especies del género Citrus son consideradas comopromisorias para el control del componente bacteriano.

Fate of Pathogens Inoculated onto Vacuum-Packaged Sliced Hams to Simulate Contamination During Packaging1

1979 ◽  
Vol 42 (6) ◽  
pp. 464-469 ◽  
Author(s):  
M. E. STILES ◽  
L.-K. NG
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Bacillus Cereus ◽  
Clostridium Perfringens ◽  
Subsequent Treatment ◽  
Vacuum Packaging ◽  
E Coli ◽  
Survival And Growth ◽  
And Staphylococcus Aureus

Ham and chopped ham from two manufacturers were contaminated with five enteropathogens: Bacillus cereus, Clostridium perfringens, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus, at time of slicing and vacuum-packaging, to simulate contamination by manufacturer. Subsequent treatment of the samples, representing sound and undesirable retail handling and consumer use conditions, indicated marked differences in the fate of the pathogens between these products and within product type between the two manufacturers. Greatest differences were observed between the chopped ham products. All pathogens, except C. perfringens, grew actively in fresh ham and chopped ham with abusive holding at 30 and 21 C. After storage at 4 or 10 C for 30 days, B. cereus and C. perfringens were no longer detected, even after subsequent holding at 30 or 21 C for 24 h. E. coli survival and growth was variable, S. typhimurium survived well and grew under some conditions and S. aureus was generally inhibited at high levels of competition.

scholarly journals Antibacterial effect of Dimethyl sulfoxide extract of Aloe vera (Aloe barbadensis) leaf gel against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae

Mediscope ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 67-74 ◽  
Author(s):  
Syed Didarul Haque ◽  
Abu Md Mayeenuddin Al Amin ◽  
Baishakhi Islam ◽  
Nazia Nazneen ◽  
Syeda Noorjahan Karim ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
Dimethyl Sulfoxide ◽  
Antibacterial Effect ◽  
Aloe Vera ◽  
Biologically Active ◽  
Diffusion Method ◽  
E Coli

An exploratory study based on laboratory experiment was carried out to determine the antibacterial effect of Dimethyl sulfoxide (DMSO) extract of Aloe vera leaf gel (DAE) against standard strains of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae in the Department of Pharmacology & Therapeutics in collaboration with the Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. DMSO extract was used in five different concentrations (100, 200, 300, 400 and 500 μg/ml). Dose dependent inhibitory effect was seen against the test organisms using disc diffusion method. Zone of inhibition (ZOI) were 8 mm, 13 mm, 15 mm, 16 mm and 21 mm against S. aureus; 0 mm, 8 mm, 13 mm, 15 mm and 18 mm against P. aeruginosa; 8 mm, 11 mm, 13 mm, 16 mm and 20 mm against E. coli; 0 mm, 9 mm, 12 mm, 14 mm and 18 mm against K. pneumoniae at 100, 200, 300, 400 and 500 μg/ml respectively. The minimum inhibitory concentration (MIC) was assessed by broth dilution technique. The MICs of DAE for S. aureus, P. aeruginosa, E. coli and K. pneumoniae were 300 μg/ml, 400 μg/ml, 400 μg/ml and 450 μg/ml respectively. From the study it was observed that DMSO extract of Aloe vera leaf gel possesses antibacterial effect against the test pathogens. The findings highlight the need for further extensive study to detect and isolate the biologically active ingredients present in the Aloe vera leaves which are responsible for antibacterial effect. Hopefully, that would lead to the discovery of new and more potent antimicrobial agents originated from Aloe vera. Mediscope Vol. 7, No. 2: July 2020, Page 67-74

scholarly journals Enterosin KP’nin Antibakteriyal Aktivitesi Üzerine Para-Hidroksi-Benzoik Asit ile Propil-Parabenin Sinerjit Etkisi

2014 ◽  
Vol 2 (1) ◽  
pp. 1 ◽  
Author(s):  
Zeliha Yıldırım ◽  
Yaselin İlk ◽  
Metin Yıldırım
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Inhibitory Activity ◽  
Hydroxybenzoic Acid ◽  
Escherichia Coli O157 ◽  
Food Preservatives ◽  
Food Preservative ◽  
E Coli ◽  
Propyl Paraben

In this study, the effects of food preservative p-hydroxybenzoic acid and propyl-paraben on the inhibitory activity of enterocin KP produced by Enterococcus faecalis KP were determined. Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella Typhimurium, resistant to enterocin KP bacteriocin, were used as target organisms. The inhibitor activity of enterosin KP (1600 AU/ml) alone or in combination with p-hydroxybenzoic acid (%0.1-0.3) and propyl-paraben (%0.008-0.16) on the growth of Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella Typhimurium were determined. The inhibitory activity of enterocin KP was increased when used in combination with p-hydroxybenzoic acid and propyl-paraben at concentrations of 0.1-0.3% and 0.008-0.016%, respectively. Furthermore, Staphylococcus aureus, E. coli O157:H7 and Salmonella Typhimurium became sensitive to enterocin KP. In conclusion, the use of enterocin KP in combination with other food preservatives principles resulted in an increase in its inhibitory activity and spectrum.

scholarly journals Draft Genome Sequences ofEscherichia coliIsolates from Wounded Military Personnel: TABLE 1 

2016 ◽  
Vol 4 (4) ◽  
Author(s):  
Brock A. Arivett ◽  
Dave C. Ream ◽  
Steven E. Fiester ◽  
Destaalem Kidane ◽  
Luis A. Actis
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Drug Resistance ◽  
Klebsiella Pneumoniae ◽  
Military Personnel ◽  
Draft Genome ◽  
Genome Sequences ◽  
E Coli ◽  
Extensive Drug Resistance

Members of theEscherichia colibacterial family have been grouped as ESKAPE (Enterococcus faecium,Staphylococcus aureus,Klebsiella pneumoniae,Acinetobacter baumannii,Pseudomonas aeruginosa, andEnterobacterspecies) pathogens because of their extensive drug resistance phenotypes and increasing threat to human health. The genomes of six extended-spectrum β-lactamase (ESBL)-producingE. colistrains isolated from wounded military personnel were sequenced and annotated.

Antagonistic Action of Lactobacillus acidophilus Toward Intestinal and Foodborne Pathogens in Associative Cultures1

1977 ◽  
Vol 40 (12) ◽  
pp. 820-823 ◽  
Author(s):  
S. E. GILLILAND ◽  
M. L. SPECK
Keyword(s):  
Escherichia Coli ◽  
Hydrogen Peroxide ◽  
Staphylococcus Aureus ◽  
Foodborne Pathogens ◽  
Lactobacillus Acidophilus ◽  
Inhibitory Effect ◽  
Enteropathogenic Escherichia Coli ◽  
Anaerobic Conditions ◽  
Antagonistic Action ◽  
E Coli

Lactobacillus acidophilus exerted antagonistic actions on growth of Staphylococcus aureus, Salmonella typhimurium, enteropathogenic Escherichia coli, and Clostridium perfringens when grown with each in associative cultures. S. aureus and C. perfringens were more sensitive to the inhibition than were S. typhimurium and E. coli. The amount of the antagonism produced varied among strains of L. acidophilus and could not be directly related to amounts of acid produced; hydrogen peroxide produced by the lactobacilli appeared to be partially responsible for the antagonistic interaction. The inhibitory effect was produced also under anaerobic conditions in a pre-reduced medium.

scholarly journals Analysis of colostrum IgA against bacteria involved in neonatal infections

2017 ◽  
Vol 15 (3) ◽  
pp. 256-261 ◽  
Author(s):  
Elizabeth Moreira Dias ◽  
Denise Bertulucci Rocha Rodrigues ◽  
Vinícius Rangel Geraldo-Martins ◽  
Ruchele Dias Nogueira
Keyword(s):  
Escherichia Coli ◽  
Molecular Weight ◽  
Staphylococcus Aureus ◽  
Klebsiella Pneumoniae ◽  
Salmonella Enteritidis ◽  
Clinical Evidence ◽  
Immune Protection ◽  
Neonatal Infections ◽  
E Coli ◽  
Iga Antibodies

ABSTRACT Objective To describe e compare the specificity of IgA antibodies against bacteria extract of Klebsiella pneumoniae , Staphylococcus aureus , Escherichia coli , and Salmonella enteritidis . Methods Colostrum samples were aseptically collected in the first 12 hours after C-section delivery. The specificity of IgA against bacteria extracts was analyzed by the Western blot. Results The findings showed proteins of high molecular weight frequently detectable in the samples. S. aureus was the most frequently found bacterium in the samples (p<0.05). Approximately 93.8, 56.3, 62.5 and 60.4% of samples presented IgA reactive to S. aureus , K. pneumoniae , S. enteritidis, and E. coli, respectively. Roughly 40% of samples showed no IgA reactive to K. pneumoniae, S. enteritidis and E. coli . Conclusion Clinical evidence of the importance of breastfeeding for the immune protection of neonates was consistent with the observed immunological findings, since most samples showed IgA reactive against the species tested. The application and development of immunotherapies during pregnancy, focused on frequently detected antigens, could be an important tool to enhance the presence of IgA in colostrum.

scholarly journals Isolation, characterization and prevention of various microbial strains in NIC unit and PIC unit

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Amin Mir ◽  
Muhammad Waqar Ashraf ◽  
Vibha Tripathi ◽  
Bilal Ahmad Mir
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
Medical Devices ◽  
Common Species ◽  
Clinical Samples ◽  
E Coli ◽  
Microbial Strains ◽  
Micro Organisms

AbstractThe health of the hospital associated persons, particularly those dealing directly with insertion of devices, are serious cause of concern for hospitals. In this study, the most prevalent organism on the surface of medical devices in PICU were CoNS (16.66%) and Staphylococcus aureus (16.66%), while in NICU the most prevalent organism was Klebsiella spp. (11.25%) among Entero-bacteriaceae group followed by Acinetobacter baumannii (10%), Escherichia coli (2.5%), CoNS (6.25%), S. aureus (6.25%) and Enterococcus faecalis (6.25%). The most common species identified from blood specimen of clinical samples shows the maximum presence of Candida sp. (60/135) followed by A. baumannii (21/135), Klebsiella Pneumoniae (20/135), Enterococci (12/135), Burkholderia cepacia complex (8/135), S. aureus (6/135), E. coli (5/135), Pseudomonas aeruginosa (3/135). Different antibiotics have been used against these micro-organisms; but Cotrimoxazole, Vancomycin have been found more effective against CoNS bacteria, Clindamycin, Tetracycline for S. aureus, Nitofurantoin for Acinetobacter, and for E. faecalis, A. baumanii, and Klebsiella, erythromycin, Colistin, and Ceftriaxone have been found more effective respectively.

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