Evaluation of the heteroantagonism between Enterobacter agglomerans strains isolated from vulture (Coragyps atratus) for production and Pseudomonas aeruginosa as developed

The heteroantagonism between Enterobacter agglomerans, isolated from the gastrointestinal tract of American vulture Coragyps atratus, and Pseudomonas aeruginosa isolated from a hospital environment was evaluated. The slow (layer) and the wells (direct) techniques were tested, using agar and soy tryptone broth pH 7.3 at 37ºC. Through the slow method from 196 tests, inhibition growth halos, related heteroantagonism phenomenon observed in 118, corresponding to 60.2% positive results. Equivalent positive results were detected using wells (direct) methodology. The seven samples of E. agglomerans tested were capable of revealing heteroantagonism in the experimental conditions; antagonism reveled by the presence of a clear growth inhibition halo. The added 1% yeast extract to media was adequate for revealing antagonisms best.

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Carbapenem-Resistant Pseudomonas aeruginosa Strains-Distribution of the Essential Enzymatic Virulence Factors Genes

Antibiotics ◽

10.3390/antibiotics10010008 ◽

2020 ◽

Vol 10 (1) ◽

pp. 8

Author(s):

Tomasz Bogiel ◽

Małgorzata Prażyńska ◽

Joanna Kwiecińska-Piróg ◽

Agnieszka Mikucka ◽

Eugenia Gospodarek-Komkowska

Keyword(s):

Pseudomonas Aeruginosa ◽

Alkaline Protease ◽

Virulence Genes ◽

Virulence Gene ◽

Hospital Environment ◽

Gene Encoding ◽

Virulence Gene Expression ◽

Carbapenem Resistant ◽

Antimicrobial Resistance Genes ◽

The Difference

Pseudomonas aeruginosa is one of the most commonly isolated bacteria from clinical specimens, with increasing isolation frequency in nosocomial infections. Herein, we investigated whether antimicrobial-resistant P. aeruginosa strains, e.g., metallo-beta-lactamase (MBL)-producing isolates, may possess a reduced number of virulence genes, resulting from appropriate genome management to adapt to a changing hospital environment. Hospital conditions, such as selective pressure, may lead to the replacement of virulence genes by antimicrobial resistance genes that are crucial to survive under current conditions. The study aimed to compare, using PCR, the frequency of the chosen enzymatic virulence factor genes (alkaline protease-aprA, elastase B-lasB, neuraminidases-nan1 and nan2, and both variants of phospholipase C-plcH and plcN) to MBL distribution among 107 non-duplicated carbapenem-resistant P. aeruginosa isolates. The gene encoding alkaline protease was noted with the highest frequency (100%), while the neuraminidase-1 gene was observed in 37.4% of the examined strains. The difference in lasB and nan1 prevalence amongst the MBL-positive and MBL-negative strains, was statistically significant. Although P. aeruginosa virulence is generally more likely determined by the complex regulation of the virulence gene expression, herein, we found differences in the prevalence of various virulence genes in MBL-producers.

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Bioprocess development for enhanced endoglucanase production by newly isolated bacteria, purification, characterization and in-vitro efficacy as anti-biofilm of Pseudomonas aeruginosa

Scientific Reports ◽

10.1038/s41598-021-87901-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Atef M. Ibrahim ◽

Ragaa A. Hamouda ◽

Noura El-Ahmady El-Naggar ◽

Fatma M. Al-Shakankery

Keyword(s):

Pseudomonas Aeruginosa ◽

Yeast Extract ◽

Statistical Design ◽

Life Time ◽

Maximum Activity ◽

Bioprocess Development ◽

Ammonium Sulfate Precipitation ◽

Face Centered ◽

Central Composite

AbstractEndoglucanase producing bacteria were isolated from Egyptian soils and the most active bacterial strain was identified as Bacillus subtilis strain Fatma/1. Plackett–Burman statistical design was carried out to assess the effect of seven process variables on endoglucanase production. Carboxymethyl cellulose (CMC), yeast extract and peptone were the most significant variables that enhanced the endoglucanase production and thus were selected for further optimization using face-centered central composite design. The highest yield of endoglucanase (32.37 U/mL) was obtained in run no. 9, using 18 g/L CMC, 8 g/L peptone, 7 g/L yeast extract and 0.1 g/L FeSO4.7H2O. The optimized medium showed about eightfold increase in endoglucanase production compared to the unoptimized medium. The produced crude enzyme was further purified by ammonium sulfate precipitation, then DEAE-Sepharose CL6B column. The purified enzyme was shown to have a molecular weight of 37 kDa. The enzyme showed maximum activity at pH 8.0, temperature of 50 °C, incubation time of 60 min. The half-life time (T1/2) was 139.53 min at 50 °C, while being 82.67 min at 60 °C. Endoglucanase at concentration of 12 U/mL effectively removed 84.61% of biofilm matrix of Pseudomonas aeruginosa with marked reduction in carbohydrate content of the biofilm from 63.4 to 7.9 μg.

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Natural Product Rottlerin Derivatives Targeting Quorum Sensing

Molecules ◽

10.3390/molecules26123745 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3745

Author(s):

Dittu Suresh ◽

Shekh Sabir ◽

Tsz Tin Yu ◽

Daniel Wenholz ◽

Theerthankar Das ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Growth Inhibition ◽

Natural Product ◽

Bacterial Growth ◽

Inhibitory Activity ◽

Chalcone Derivatives ◽

Synthetic Strategy ◽

The Mannich Reaction ◽

Bacterial Growth Inhibition

Rottlerin is a natural product consisting of chalcone and flavonoid scaffolds, both of which have previously shown quorum sensing (QS) inhibition in various bacteria. Therefore, the unique rottlerin scaffold highlights great potential in inhibiting the QS system of Pseudomonas aeruginosa. Rottlerin analogues were synthesised by modifications at its chalcone- and methylene-bridged acetophenone moieties. The synthesis of analogues was achieved using an established five-step synthetic strategy for chalcone derivatives and utilising the Mannich reaction at C6 of the chromene to construct morpholine analogues. Several pyranochromene chalcone derivatives were also generated using aldol conditions. All the synthetic rottlerin derivatives were screened for QS inhibition and growth inhibition against the related LasR QS system. The pyranochromene chalcone structures displayed high QS inhibitory activity with the most potent compounds, 8b and 8d, achieving QS inhibition of 49.4% and 40.6% and no effect on bacterial growth inhibition at 31 µM, respectively. Both compounds also displayed moderate biofilm inhibitory activity and reduced the production of pyocyanin.

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Characterization of Phospholipase Activity of the Pseudomonas aeruginosa Type III Cytotoxin, ExoU

Journal of Bacteriology ◽

10.1128/jb.187.3.1192-1195.2005 ◽

2005 ◽

Vol 187 (3) ◽

pp. 1192-1195 ◽

Cited By ~ 42

Author(s):

Hiromi Sato ◽

Jimmy B. Feix ◽

Cecilia J. Hillard ◽

Dara W. Frank

Keyword(s):

Pseudomonas Aeruginosa ◽

Substrate Specificity ◽

Yeast Extract ◽

Enzyme Activation ◽

Phospholipase Activity ◽

Eukaryotic Protein ◽

Type Iii

ABSTRACT Recombinant ExoU (rExoU) and yeast extract were used to optimize an in vitro phospholipase assay as a basis for identifying the mechanism for enzyme activation and substrate specificity. Our results support a model in which a eukaryotic protein cofactor or complex facilitates the interaction of rExoU with phospholipid substrates.

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Pseudomonas aeruginosa Genome Evolution in Patients and under the Hospital Environment

Pathogens ◽

10.3390/pathogens3020309 ◽

2014 ◽

Vol 3 (2) ◽

pp. 309-340 ◽

Cited By ~ 9

Author(s):

Céline Lucchetti-Miganeh ◽

David Redelberger ◽

Gaël Chambonnier ◽

François Rechenmann ◽

Sylvie Elsen ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Genome Evolution ◽

Hospital Environment

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Evaluación del método dilución neutralización aplicado a un desinfectante según la Norma Técnica Colombiana 5473 de 2007

Universitas Scientiarum ◽

10.11144/javeriana.sc17-1.aotd ◽

2012 ◽

Vol 17 (1) ◽

pp. 72

Author(s):

Janeth Arias-Palacios ◽

Libardo Hernandez-Esquivel ◽

Juan Carlos Marín-Díaz ◽

Natalia Navarro-Peña ◽

Natalia Santos-Arévalo

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Bovine Serum Albumin ◽

Serum Albumin ◽

Key Words ◽

Bactericidal Activity ◽

Bovine Serum ◽

Enterococcus Hirae ◽

Experimental Conditions ◽

Logarithmic Reduction

Objective. Evaluate the dilution-neutralization method proposed in the Colombian Technical Norm 5473/07, by using a gel, alcoholbased disinfectant. Materials and methods. This study was done using Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538, and Enterococcus hirae ATCC 10541 as the assay microorganisms. The study was carried out at 20±1°C as obligatory temperature and additionally at 36±1°C. Four contact times between microorganisms and the disinfectant were evaluated (0, 2, 5 and 10 minutes). The assay was done both under clean conditions (0.3 g/L of bovine serum albumin), and unclean conditions (3 g/L of bovine serum albumin and 3g/L of sheep erythrocytes). Results. The implementation of this method produced precise results in all of the six repetitions used during the assay. The obtained results demonstrated a logarithmic reduction higher than five, demonstrating the bactericidal activity exerted by the disinfectant on the control microorganisms. The established experimental conditions and methodology did not affect negatively the growth of any of the strains of microorganisms. Similarly, the neutralizing used did not inhibit the development of the microorganisms of the assay. Conclusions. The method was verified by means of the fulfillment of the limits set by the rule. Our results suggest that the method evaluated by means of the implementation of the protocol established in the Colombian Technical Norm 5473/07, allows evaluating the effectiveness of a disinfectant under selected and controlled experimental conditions. Key words: disinfection, clean conditions, unclean conditions, dilution-neutralization method, logarithmic reduction.

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l-Pyroglutamate Spontaneously Formed from l-Glutamate Inhibits Growth of the Hyperthermophilic Archaeon Sulfolobus solfataricus

Applied and Environmental Microbiology ◽

10.1128/aem.67.8.3650-3654.2001 ◽

2001 ◽

Vol 67 (8) ◽

pp. 3650-3654 ◽

Cited By ~ 21

Author(s):

Chan B. Park ◽

Sun Bok Lee ◽

Dewey D. Y. Ryu

Keyword(s):

Cell Growth ◽

Growth Inhibition ◽

Yeast Extract ◽

Formation Rate ◽

Sulfolobus Solfataricus ◽

Methionine Sulfoxide ◽

Inhibitory Effect ◽

Culture Conditions ◽

Culture Broth ◽

Cell Growth Inhibition

ABSTRACT Identification of physiological and environmental factors that limit efficient growth of hyperthermophiles is important for practical application of these organisms to the production of useful enzymes or metabolites. During fed-batch cultivation of Sulfolobus solfataricus in medium containing l-glutamate, we observed formation of l-pyroglutamic acid (PGA). PGA formed spontaneously from l-glutamate under culture conditions (78°C and pH 3.0), and the PGA formation rate was much higher at an acidic or alkaline pH than at neutral pH. It was also found that PGA is a potent inhibitor of S. solfataricus growth. The cell growth rate was reduced by one-half by the presence of 5.1 mM PGA, and no growth was observed in the presence of 15.5 mM PGA. On the other hand, the inhibitory effect of PGA on cell growth was alleviated by addition of l-glutamate or l-aspartate to the medium. PGA was also produced from the l-glutamate in yeast extract; the PGA content increased to 8.5% (wt/wt) after 80 h of incubation of a yeast extract solution at 78°C and pH 3.0. In medium supplemented with yeast extract, cell growth was optimal in the presence of 3.0 g of yeast extract per liter, and higher yeast extract concentrations resulted in reduced cell yields. The extents of cell growth inhibition at yeast extract concentrations above the optimal concentration were correlated with the PGA concentration in the culture broth. Although other structural analogues ofl-glutamate, such as l-methionine sulfoxide, glutaric acid, succinic acid, and l-glutamic acid γ-methyl ester, also inhibited the growth of S. solfataricus, the greatest cell growth inhibition was observed with PGA. We also observed that unlike other glutamate analogues,N-acetyl-l-glutamate enhanced the growth of S. solfataricus. This compound was stable under cell culture conditions, and replacement of l-glutamate with N-acetyl-l-glutamate in the medium resulted in increased cell density.

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PREVALÊNCIA DE MICRORGANISMOS EM BANDEJAS UTILIZADAS PELA ENFERMAGEM NA ADMINISTRAÇÃO DE MEDICAMENTOS EM AMBIENTE HOSPITALAR

REVISTA INTERDISCIPLINAR EM CIÊNCIAS DA SAÚDE E BIOLÓGICAS – RICSB ◽

10.31512/ricsb.v3i2.3199 ◽

2020 ◽

Vol 3 (2) ◽

pp. 24

Author(s):

Cristiane Güths da Silva De Freitas ◽

Keli Jaqueline Staudt ◽

Kelly Helena Khün ◽

Izabel Almeida Alves ◽

Maria Cristina Meneghete

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Klebsiella Oxytoca ◽

Pseudomonas Stutzeri ◽

Rio Grande ◽

Rio Grande Do Sul ◽

Enterobacter Agglomerans ◽

De Se

Introdução: Os hospitais constituem importante fonte de infecções, pois, abrigam uma vasta gama de microrganismos, principalmente bactérias. A limpeza e desinfecção de superfícies em ambientes hospitalares são subsídios elementares e eficazes como medidas de controle para romper a cadeia epidemiológica das infecções. Objetivo: Verificar a prevalência de microrganismos em bandejas utilizadas pela enfermagem para a administração de medicamentos em ambiente hospitalar, através do crescimento dos mesmos por técnicas microbiológicas. Métodos: Trata-se de uma pesquisa do tipo transversal, de prevalência, com abordagem quantitativa realizada em um hospital de médio porte da região Noroeste do Estado do Rio Grande do Sul, no segundo semestre de 2015. A coleta das amostras se deu por meio da técnica de swab, que consistiu em deslizar um swab na superfície das bandejas utilizadas para a administração dos medicamentos. Para a análise dos dados foi realizada a pesquisa microbiológica e utilizada a estatística descritiva mediante a distribuição da frequência. Resultados: Os microrganismos isolados foram: Staphylococcus coagulase negativa, Acinetobacter baumanni, Enterobacter agglomerans, Klebsiella oxytoca, Klebsiella ozaenae, Staphylococcus aureus, Acinetobacter lwoffii, Pseudomonas stutzeri, Pseudomonas aeruginosa. Conclusão: Demonstrando a importância de se realizar os processos de higienização correta das mãos, dos materiais, dos utensílios, dentre outras, como forma possível de reduzir a transferência de patógenos entre profissionais, pacientes e ambiente.

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FLORAL EXTRACT OF Tibouchina granulosa (DESR.) COGN. PHYTOCHEMISTRY PROSPECTION, AND ANTIBACTERIAL ACTIVITY

Ipê Agronomic Journal ◽

10.37951/2595-6906.2021v5i1.6880 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1-9

Author(s):

Antonio Carlos Pereira de Menezes Filho ◽

Matheus Vinícius Abadia Ventura ◽

Carlos Frederico de Souza Castro

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Antibacterial Activity ◽

Enterococcus Faecalis ◽

Floral Organ ◽

Salt Formation ◽

Bacterial Strains ◽

Positive Results

Tibouchina granulosa is a species that blooms annually in several regions of Brazil. This species is still little explored in terms of phytocompounds in all organs of this plant, especially the floral organ. Flowers of T. granulosa were collected in the municipality of Rio Verde, Goiás, Brazil, in 2021. The hydroethanolic floral extract was prepared by maceration and qualitative phytochemical (colorimetric reactions and salt formation) and antibacterial analyzes performed and the results expressed in millimeters of inhibition at different concentrations in mg mL-1. Several phytochemical classes were observed with positive results, especially for alkaloids, phenolics, oxylates, saponins, carbohydrates and tannins. As for the bacterial assay, potential antibacterial activity was observed for all bacterial strains tested, except for Salmonella serovar Thyphymurium and serovar Enteritidis. Expressive inhibitions were observed for Enterococcus faecalis > Pseudomonas aeruginosa > Staphylococcus aureus and Escherichia coli at the highest concentrations between 100-50 mg mL-1. The floral extract of Tibouchina granulosa showed phytotherapeutic potential with the presence of several phytochemical groups and expressive antibacterial activity.

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Evaluation of Moringa Peregrina (Forsk) Fiori, Leaf and Seed Extract Against Multidrug Resistant Strains of Bacteria and Fungus of Clinical Origin

Archives of Ecotoxicology ◽

10.36547/ae.2021.3.1.20-26 ◽

2021 ◽

Vol 3 (1) ◽

pp. 20-26

Author(s):

Suliman Mansour Albalawi ◽

Abdulrahman K. Al-Asmari ◽

Syed Rafatullah ◽

Maysa Mahfoud

Keyword(s):

Pseudomonas Aeruginosa ◽

Growth Inhibition ◽

Acinetobacter Baumannii ◽

Bacterial Resistance ◽

Antimicrobial Agents ◽

Colorimetric Assay ◽

Multidrug Resistant ◽

Klebsiella Pneumonia ◽

Isolation And Purification ◽

Moringa Peregrina

The emergence of antibiotic resistant microorganism strains has become a critical concern in the treatment of infectious diseases and makes the search of an alternative therapy a must. The study was designed to evaluate the in vitro antimicrobial activities of the Moringa peregrina (MP) leave (MPL) and seed (MPS) extracts. Antimicrobial assays were performed using a microplate growth inhibition assay against 11 multidrug-resistant (MDR) strains. Following qualitative analysis, dose-response assays were performed using the MTT colorimetric assay. The results showed a strong correlation between the MPL and MPS extract concentration and growth inhibition (P<0.001). MP extract revealed a remarkable antimicrobial effect and inhibited the growth and survival of MDR pathogens which include Escherichia coli; Pseudomonas aeruginosa; Klebsiella pneumonia; Acinetobacter baumannii; Staphylococcus aureus between (88.6-94.7 %) and between (62.3- 88.7%) against Candida Kefyer; Candida parapsilosis; Candida albicans; Candida glabrata; Aspergillus flavus and Fusarium oxysporum. MIC50 ranging from ≤6.25 to 25 mg/mL. Acinetobacter baumannii and Pseudomonas aeruginosa were the most susceptible to MP extracts (MIC50 < 6.25 mg/mL). These results support the use of MP in Arab traditional medicine as natural antimicrobial agents. Additionally, the use of such naturally occurring adjuvant derived from medicinal plants can be used as an adjuvant with synthetic antibiotics to combat bacterial resistance and to enhance the antibacterial potential. Further studies are recommended on isolation and purification of novel antimicrobial molecules to treat the infections caused by microbes.

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