scholarly journals Molecular detection of virulence factors and biofilm formation in Pseudomonas aeruginosa obtained from different clinical specimens in Bandar Abbas

2019 ◽  
Author(s):  
Nima Bahador ◽  
Saeed Shoja ◽  
Foroogh Faridi ◽  
Banafsheh Dozandeh-Mobarrez ◽  
Fatemeh Izadpanah Qeshmi ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Virulence Factors ◽  
Antimicrobial Susceptibility ◽  
Biofilm Formation ◽  
Opportunistic Pathogen ◽  
Clinical Specimens ◽  
Biofilm Production ◽  
Bandar Abbas ◽  
Susceptibility Patterns

Background and Objectives: Pseudomonas aeruginosa is a ubiquitous opportunistic pathogen. The presence of several virulence factors such as exotoxin and exoenzyme genes and biofilm may contribute to its pathogenicity. The purpose of this study was to investigate the presence of toxA, exoU and exoS, the determination of biofilm production and antimicrobial susceptibility patterns among clinical isolates of P. aeruginosa. Materials and Methods: In this study, 75 isolates of P. aeruginosa were recovered from various clinical specimens. Antimi- crobial susceptibility pattern of isolates were identified. Virulence genes toxA, exoU and exoS were determined using PCR. The ability of biofilm production was assessed. Results: Antimicrobial susceptibility test showed that 12 strains were resistant to more than 8 antibiotics (17.14%). The most effective antibiotic was colistin as 98.6% of isolates were sensitive. The frequencies of exoU and exoS genes were detected as 36.6% and 55.7%, respectively. In addition, 98.6% of the isolates were biofilm producers. Exotoxin A was detected in sixty-eight isolates (95.7%). Conclusion: The findings of this study showed that, the presence of P. aeruginosa exotoxin and exoenzyme genes, particu- larly, the exoU gene is the most common virulence factors in the bacterial isolates from urine samples. Biofilm is a serious challenge in the treatment of P. aeruginosa infection.

Isolation and Identification of Fungal Isolates caused Otomycosis from some Hospitals and Clinics in Mosul with Determination of Their Virulence Factors

2021 ◽  
Vol 26 (4) ◽  
Author(s):  
Nabeel Al-Sharrad ◽  
Muhammad A. Al-Kataan ◽  
Maha A. Al-Rejaboo
Keyword(s):  
Fungal Infection ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Fungal Pathogens ◽  
Candida Parapsilosis ◽  
Isolation And Identification ◽  
Fungal Isolates ◽  
Biofilm Production ◽  
Etiological Agents

Otomycosis is a fungal infection that frequently involves the external auditory canal. In this study, we aimed to isolation and identification the fungal isolates as etiological agents of otomycosis from some hospitals and clinics in Mosul with determination of their virulence factors of fungal etiological agents. Positive fungal infection was found in (43) samples (71.6%). The most common fungal pathogens were Candida and Aspergillus species, with Candida parapsilosis being the predominant isolates in (11) samples (16.6%). Otomycosis was more common in Female in (26) samples (43.3%).Otomycosis was the highest prevalence aged group 15-40 years (19) samples (31.3%). The present study of virulence factors revealed that the highest biofilm formation isolates were C. parapsilosis is (10) isolates which were distributed between (2) strong and (8) weak biofilm formation.Where C.trpicales, was recorded as least isolates for biofilm production.

scholarly journals Plantain Herb Extracts significantly attenuate the quorum sensing-controlled virulence factors and inhibit biofilm formation in Pseudomonas aeruginosa PAO1

2019 ◽  
Vol 78 ◽  
pp. 01004
Author(s):  
Shan Li ◽  
Jiangning Yao ◽  
Haoming Li
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Opportunistic Pathogen ◽  
Significant Inhibition ◽  
Control Group ◽  
Produce Cell ◽  
Group B ◽  
Herb Extracts

Pseudomonas aeruginosa is a Gram-negative organism that can survive under harsh conditions, and it is also an opportunistic pathogen that can produce cell-associated extracellular virulence factors. Several of these virulence factors have been demonstrated to be regulated by quorum sensing (QS). Plantain Herb has been used as antibacterial agents for many centuries in China. In this study, we analyzed Plantain Herb Extracts (PHE) at the concentration of 16 μg/mL (Group A, MIC), 8 μg/mL (Group B, 1/2 MIC) and 4 μg/mL (Group C, 1/4 MIC) for inhibition of the virulence factors production and biofilm formation in P. aeruginosa PAO1. The virulence factors included pyocyanin, rhamnolipids, protease and alginate. PHE showed significant inhibition of virulence factors as compared to the control group without interfering its growth. Thus, PHE might be a potent QS inhibitor and anti-biofilm agent in the treatment of Pseudomonas aeruginosa infections.

scholarly journals The Prevalence of Exoenzyme S Gene in Multidrug-Sensitive and Multidrug-Resistant Pseudomonas aeruginosa Clinical Strains

2017 ◽  
Vol 66 (4) ◽  
pp. 427-431 ◽  
Author(s):  
Tomasz Bogiel ◽  
Aleksander Deptuła ◽  
Joanna Kwiecińska-Piróg ◽  
Małgorzata Prażyńska ◽  
Agnieszka Mikucka ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Virulence Factors ◽  
Multidrug Resistant ◽  
Hospital Environment ◽  
Antibiotic Resistant ◽  
Exoenzyme S ◽  
Clinical Specimens ◽  
Antimicrobial Resistance Genes ◽  
The Difference ◽  
Susceptibility Patterns

Pseudomonas aeruginosa rods are one of the most commonly isolated microorganisms from clinical specimens, usually responsible for nosocomial infections. Antibiotic-resistant P. aeruginosa strains may present reduced expression of virulence factors. This fact may be caused by appropriate genome management to adapt to changing conditions of the hospital environment. Virulence factors genes may be replaced by those crucial to survive, like antimicrobial resistance genes. The aim of this study was to evaluate, using PCR, the occurrence of exoenzyme S-coding gene (exoS) in two distinct groups of P. aeruginosa strains: 83 multidrug-sensitive (MDS) and 65 multidrug-resistant (MDR) isolates. ExoS gene was noted in 72 (48.7%) of the examined strains: 44 (53.0%) MDS and 28 (43.1%) MDR. The observed differences were not statistically significant (p = 0.1505). P. aeruginosa strains virulence is rather determined by the expression regulation of the possessed genes than the difference in genes frequency amongst strains with different antimicrobial susceptibility patterns.

scholarly journals Correlation of biofilm production with antibiotic susceptibility pattern of Pseudomonas aeruginosa from various clinical specimens

2022 ◽  
Vol 13 (1) ◽  
pp. 88-92
Author(s):  
M Swapna ◽  
G Sumathi ◽  
M Anitha
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance ◽  
Biofilm Formation ◽  
Antibiotic Sensitivity ◽  
Microtiter Plate ◽  
Resistance Pattern ◽  
Sensitivity Testing ◽  
Clinical Specimens ◽  
Biofilm Production ◽  
Microbiological Methods

Background: Pseudomonas aeruginosa is one of the most prevalent nosocomial pathogens that cause a life-threatening infection. One of the important characteristics of P. aeruginosa is biofilm formation which leads to antibiotic resistance. Aims and Objectives: The aim of the study was to study the antibiotic resistance pattern of P. aeruginosa isolates and correlation with their biofilm-production. Materials and Methods: A total of 87 P. aeruginosa isolates from different clinical specimens were processed and confirmed by conventional microbiological methods as per standard methodology. Antibiotic sensitivity testing was done for all isolates. Biofilm producing isolates were identified by the microtiter plate method (MTPM). Results: Of 87 P. aeruginosa isolates, majority were from pus 33 (38%), followed by urine 26 (30%), sputum 19 (22%), body fluids 7 (8%), and blood 2 (2%). Biofilm producing isolates showed more resistance in comparison to non-biofilm producers. The observed difference between biofilm formation for multidrug resistant and susceptible isolates was found to be statistically significant. Conclusion: MTPM method was an effective test for detection of biofilm formation and was also able to verify biofilm production by P. aeruginosa. This indicated a higher propensity among the clinical isolates of P. aeruginosa to form biofilm and revealed a positive correlation between biofilm formation and antibiotic resistance. This indicates the need for testing of even susceptible isolates for virulence factors such as biofilm production.

Characteristics of Pseudomonas aeruginosa Isolated From Whirlpools and Bathers

1985 ◽  
Vol 6 (10) ◽  
pp. 407-412 ◽  
Author(s):  
Anita K. Highsmith ◽  
Phuong Nhan Le ◽  
Rima F. Khabbaz ◽  
Van P. Munn
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Virulence Factors ◽  
Virulence Factor ◽  
Antimicrobial Susceptibility ◽  
Enzyme Production ◽  
Extracellular Enzyme ◽  
Skin Flora ◽  
Low Levels ◽  
Toxic Reactions ◽  
Susceptibility Patterns

AbstractPseudomonas aeruginosa is the most frequently isolated microorganism from whirlpool water and lesions associated with outbreaks of dermatitis and folliculitis related to whirlpool exposure. Strains were selected from 19 outbreaks of P. aeruginosa infections (1977 to 1983) associated with whirlpool use; they were examined to determine if the strains possessed unique virulence factors or characteristics that might aid in their selection in the environment.P. aeruginosa, 011, was the predominant serotype isolated from whirlpool water as well as from bathers with dermatitis or folliculitis, followed by serotypes 09, 04, and 03. Antimicrobial susceptibility patterns were similar for all strains. Strains of P. aeruginosa from bathers and water demonstrated statistically significant differences in extracellular enzyme production compared with control strains. P. aeruginosa, serotypes 09 and 011, were found to be sensitive to low levels of chlorine. These data suggest that, if adequate levels of free available chlorine are maintained, P. aeruginosa should have little opportunity to persist in whirlpools.A bather's risk of P. aeruginosa dermatitis or folliculitis appears to be affected primarily by three factors: 1) immersion in water colonized by P. aeruginosa, 2) skin hydration with altered skin flora, and 3) toxic reactions to extracellular enzyme or exotoxins produced by P. aeruginosa. Although a single virulence factor was not identified from the results of this study, there are some indications that the enzymes produced by these microorganisms play an important role in the pathogenesis of disease associated with whirlpool use.

Phenotypic heterogeneity of Pseudomonas aeruginosa isolates in the protected nature park ‘Palić’ (Serbia)

2016 ◽  
Vol 16 (5) ◽  
pp. 1370-1377 ◽  
Author(s):  
Bojana Vujović ◽  
Smilja Teodorović ◽  
Željka Rudić ◽  
Mile Božić ◽  
Vera Raičević
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Virulence Factors ◽  
Environmental Conditions ◽  
Biofilm Formation ◽  
Phenotypic Diversity ◽  
Production Capacity ◽  
Wide Distribution ◽  
Clear Correlation ◽  
Protective Mechanism ◽  
Biofilm Production

Pseudomonas aeruginosa is a globally distributed environmental bacterium, which is also a significant opportunistic pathogen of humans, animals and plants. It is considered that wide distribution of this bacterium is connected with its most significant constitutive property to form biofilms, and that this multicellular mode of growth, predominant in nature, serves as a protective mechanism against unfavourable environmental conditions. The work presented here examines the phenotypic diversity of Pseudomonas aeruginosa environmental isolates with respect to biofilm production capacity under different environmental conditions (temperature, pH, NaCl), production of virulence factors, and motility. The purpose of this work is to present the production of two quorum sensing-regulated virulence factors (rhamnolipids and pyocyanin), explore different motility tests (swimming, swarming and twitching) and discover potential relationship between assessed phenotypic features. Obtained results delineate environmental conditions coinciding with biofilm production and suggest a high correlation between rhamnolipid production levels and biofilm formation. Rhamnolipids affect motility competence, yet only the flagellum-mediated swimming motility has significant impact on the biofilm formation potential. Although it is challenging to demarcate a definitive, clear correlation between parameters tested, rhamnolipid content appears to serve as a link between the tested phenotypic factors.

scholarly journals Inhibition of Virulence Factors and Biofilm Formation by Wogonin Attenuates Pathogenicity of Pseudomonas aeruginosa PAO1 via Targeting pqs Quorum-Sensing System

2021 ◽  
Vol 22 (23) ◽  
pp. 12699
Author(s):  
Shiwei Wang ◽  
Yuqi Feng ◽  
Xiaofeng Han ◽  
Xinyu Cai ◽  
Liu Yang ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Extracellular Polysaccharide ◽  
Fruit Fly ◽  
Opportunistic Pathogen ◽  
Signal Molecule ◽  
Conventional Antibiotics

Pseudomonas aeruginosa, an important opportunistic pathogen, is capable of producing various virulence factors and forming biofilm that are regulated by quorum sensing (QS). It is known that targeting virulence factor production and biofilm formation instead of exerting selective pressure on growth such as conventional antibiotics can reduce multidrug resistance in bacteria. Therefore, many quorum-sensing inhibitors (QSIs) have been developed to prevent or treat this bacterial infection. In this study, wogonin, as an active ingredient from Agrimonia pilosa, was found to be able to inhibit QS system of P. aeruginosa PAO1. Wogonin downregulated the expression of QS-related genes and reduced the production of many virulence factors, such as elastase, pyocyanin, and proteolytic enzyme. In addition, wogonin decreased the extracellular polysaccharide synthesis and inhibited twitching, swimming, and swarming motilities and biofilm formation. The attenuation of pathogenicity in P. aeruginosa PAO1 by wogonin application was further validated in vivo by cabbage infection and fruit fly and nematode survival experiments. Further molecular docking analysis, pathogenicity examination of various QS-related mutants, and PQS signal molecule detection revealed that wogonin could interfere with PQS signal molecular synthesis by affecting pqsA and pqsR. Taken together, the results indicated that wogonin might be used as an anti-QS candidate drug to attenuate the infection caused by P. aeruginosa.

scholarly journals An examination of potential differences in biofilm production among different genotypes of Pseudomonas aeruginosa

2014 ◽  
Vol 66 (1) ◽  
pp. 117-121 ◽  
Author(s):  
Zorica Vasiljevic ◽  
B. Jovcic ◽  
Ivana Cirkovic ◽  
Slobodanka Djukic
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Microtiter Plate ◽  
Band Pattern ◽  
Hospital Environment ◽  
Plate Test ◽  
Clinical Specimens ◽  
Biofilm Production

In the present study, we have examined if there is any difference in biofilm production among different genotypes of Pseudomonas aeruginosa. The study investigated 526 non-duplicate P. aeruginosa isolated from clinical specimens and from a hospital environment. Isolates were grouped into thirty-five genotypes based on an identical ERIC2-band pattern. Biofilm formation was quantified by the microtiter plate test and all strains were classified into the following categories: no biofilm producers (0), weak (+), moderate (+), or strong (+++) biofilm producers. Only 2.45% of examined strains were not biofilm producers. Among biofilm producers, 39.26% were strong biofilm producers, 34.36% were moderate biofilm producers, while 23.93% were weak biofilm producers. Although the majority of strong biofilm producers were in genotype groups 2 and 3, the degree of in vitro biofilm formation in our study was not significantly affected by the genotype of Pseudomonas aeruginosa. In this study, we demonstrated that the degree of in vitro biofilm formation is not significantly affected by the genotype of Pseudomonas aeruginosa.

scholarly journals Quorum Sensing Inhibitory Activities of Oridonin in Pseudomonas Aeruginosa

2021 ◽  
Vol 233 ◽  
pp. 02044
Author(s):  
Jing Huang ◽  
Haoming Li
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quorum Sensing ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Opportunistic Pathogen ◽  
Active Components ◽  
Produce Cell ◽  
Potential Strategy ◽  
Rabdosia Rubescens ◽  
Infective Agent

Pseudomonas aeruginosa is an opportunistic pathogen, and it can produce cell-associated and extracellular virulence factors. Several of these virulence factors have been demonstrated to be regulated by quorum sensing (QS). Disabling QS system with anti-infective agent is considered as a potential strategy to prevent bacterial infection. Rabdosia rubescens has been used as antibacterial agents for many centuries in China. In this study, Oridonin, the major active components of Rabdosia rubescens, was tested for QS inhibition in Pseudomonas aeruginosa. QS inhibitory activity is demonstrated by reduction in pyocyanin (58.4%), rhamnolipids (64.3%), elastase (58.6%), and protease (49.1%) in Pseudomonas aeruginosa PAO1 at 125 µg/ml (MIC) concentration. Biofilm formation by Pseudomonas aeruginosa PAO1 was reduced considerably (40.3-57.7%) over control. These findings suggest that Oridonin might be a potent Quorum Sensing Inhibitor (QSI) and anti-biofilm agent in the treatment of Pseudomonas aeruginosa infections.

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