Pseudomonas AeroginosaNCT07469436
mexB Efflux Pump Gene Expression, Activity and Biofilm Formation in Clinical Isolates of Pseudomonas Aeruginosa
An observational study of Pseudomonas Aeroginosa, run by Assiut University.
Trial summary
1. Detection of expression level of mexB efflux pump gene in multidrug resistant clinical isolates of Pseudomonas aeruginosa by real time PCR(QRT-PCR). 2. Phenotypic detection of efflux pump activity in multidrug resistant clinical isolates of Pseudomonas aeruginosa. 3. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Pseudomonas Aeroginosa
- What is being tested?
- Real time PCR
- How many people
- 80 participants
- Where
- No sites listed yet
- Study dates
- Apr 2026to Jan 2028
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: Patients with multidrug resistant clinical isolates of Pseudomonas aeruginosa.
Who may be able to join
- Clinical isolates confirmed as Pseudomonas aeruginosa by microbiological testing.
- Isolates collected from different clinical specimens (e.g., wound swabs, sputum, urine, blood, and catheters).
Who cannot join
- Bacterial species other than Pseudomonas aeruginosa.
- Repeated clinical isolates from the same patient.
- Repeated clinical specimens from different sources of the same patient.
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Relationship Between mexB Efflux Pump Gene Expression, Efflux Pump Activity and Biofilm Formation in Multidrug Resistant Clinical Isolates of Pseudomonas Aeruginosa
- Detection of expression level of mexB efflux pump gene in multidrug resistant clinical isolates of Pseudomonas aeruginosa by real time PCR(QRT-PCR).
- Phenotypic detection of efflux pump activity in multidrug resistant clinical isolates of Pseudomonas aeruginosa.
- Phenotypic detection of biofilm formation and its degree (strong-moderate-weak) in multidrug resistant clinical isolates of Pseudomonas aeruginosa.
- Relationship between expression level of mexB efflux pump gene and degree of biofilm formation in multidrug resistant clinical isolates of Pseudomonas aeruginosa.
Read the detailed description
Pseudomonas aeruginosa is an opportunistic gram-negative pathogen, causing life threatening nosocomial infections including respiratory system, urinary system and skin wounds (1). P. aeruginosa exhibits resistance to a range of antibiotic classes, including aminoglycosides, carbapenems, beta-lactams, quinolones, and cephalosporins (2). Frequent occurrence of drug resistance is due to many virulence factors in P. aeruginosa such as flagella, pili, lipopolysaccharides, secreted enzymes like DNase and lipase, toxins, and pigments as pyocyanin which play crucial roles in tissue damage and immune suppression. Multiple resistant mechanisms are developed by P. aeruginosa (3). Two prominent mechanisms, biofilm formation and efflux pump activity among other mechanisms, play an important role in persistence and antibiotic resistance (4). Biofilm formation produced by P. aeruginosa is a complex phenomenon that promotes antibiotic resistance and shields the pathogen from the host immune system. This results in severe clinical outcomes in critically ill patients (5). There are about 12 resistance-nodulation-division (RND) families of efflux pumps in P. aeruginosa. The mexAB-oprM multidrug efflux pump system of P. aeruginosa is involved in resistance (6). Efflux pumps play a role in biofilm formation by influencing Physical-chemical interactions, mobility, gene regulation, quorum sensing (QS), extracellular polymeric substances (EPS), and toxic compound extrusion (6)(7). It has been demonstrated that MexAB-OprM plays a role in the resistance of aztreonam, gentamicin, tetracycline and tobramycin in biofilm structures of P. aeruginosa (8). MexB is the most critical and specific gene for efflux activity within the MexAB-OprM system and contributes to antibiotic resistance in Pseudomonas aeruginosa (9).
- Conditions
- Pseudomonas Aeroginosa
- Being tested
- Real time PCR
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Real time PCRGenetic
Clinical isolates of Pseudomonas aeruginosa will undergo RNA extraction followed by cDNA (complementary DNA) synthesis. Quantitative real-time PCR will be performed using specific primers for the mexB efflux pump gene, and SYBR Green will be used to quantify gene expression. Housekeeping genes (e.g., rpoD or 16S rRNA) will serve as internal controls. The procedure allows precise quantification of mexB expression levels in each isolate.
What is being measured
The primary outcome is the main question the study is designed to answer.
Detection of mexB efflux pump gene expression level in multidrug resistant clinical isolates of Pseudomonas aeruginosa
molecular detection of mexB efflux pump gene expression level by real time PCR (QRT-PCR)
Measured: one year
Secondary outcomes (2)
Detection of efflux pump activity in multidrug resistant clinical isolates of Pseudomonas aeruginosa
Phenotypic detection of efflux pump activity by MIC (minimal inhibitory concentration) testing with efflux pump inhibitors (EPIs) using Phenylalanine-arginine β-naphthylamide (PAβN)in P. aeruginosa
Measured: one year
Detection of degree of biofilm formation (strong-moderate-weak) in multidrug resistant clinical isolates of Pseudomonas aeruginosa
Phenotypic detection of biofilm formation using microtiter plate assay and assess the degree of biofilm (strong-moderate-weak)
Measured: one year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Mar 2026
- Study startApr 2026 (estimated)
- Primary completionDec 2027 (estimated)
- Study completionJan 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (9)Papers the sponsor has linked to this study.
- Other trials for Pseudomonas AeroginosaStudies of the same condition, open and under way.
- More trials run by Assiut UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Cross-sectional
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Rehab Abdelnasser Mohammed Omran, Assiut University
- Investigators
- Assiut University, Study director, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07469436
- Sponsor's protocol ID
- RBMEPGEEPAABFIMRCIOPA
- Status last verified
- Mar 2026
- First submitted
- 5 Mar 2026
- Last updated
- 17 Mar 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Li XF, Shi HQ, Liang Y, Li J, Jiang B, Song GB. Interaction of biofilm and efflux pump in clinical isolates of carbapenem resistant P. aeruginosa. Eur Rev Med Pharmacol Sci. 2022 Mar;26(5):1729-1737. doi: 10.26355/eurrev_202203_28242.
PubMed 35302222Soltani Borchaloee A, Moosakazemi Mohammadi LS, Khosh Ravesh R, Allameh SF, Tabatabaie Poya FS, Fatehi MA. Prevalence of Biofilm and Efflux Pump Genes Expression by PCR and Antibiotic Resistance Pattern in Pseudomonas Aeruginosa. Arch Razi Inst. 2024 Dec 31;79(6):1281-1286. doi: 10.32592/ARI.2024.79.6.1281. eCollection 2024 Dec.
PubMed 40599435Liao C, Huang X, Wang Q, Yao D, Lu W. Virulence Factors of Pseudomonas Aeruginosa and Antivirulence Strategies to Combat Its Drug Resistance. Front Cell Infect Microbiol. 2022 Jul 6;12:926758. doi: 10.3389/fcimb.2022.926758. eCollection 2022.
PubMed 35873152Ugwuanyi FC, Ajayi A, Ojo DA, Adeleye AI, Smith SI. Evaluation of efflux pump activity and biofilm formation in multidrug resistant clinical isolates of Pseudomonas aeruginosa isolated from a Federal Medical Center in Nigeria. Ann Clin Microbiol Antimicrob. 2021 Feb 2;20(1):11. doi: 10.1186/s12941-021-00417-y.
PubMed 33531042Karballaei Mirzahosseini H, Hadadi-Fishani M, Morshedi K, Khaledi A. Meta-Analysis of Biofilm Formation, Antibiotic Resistance Pattern, and Biofilm-Related Genes in Pseudomonas aeruginosa Isolated from Clinical Samples. Microb Drug Resist. 2020 Jul;26(7):815-824. doi: 10.1089/mdr.2019.0274. Epub 2020 Jan 23.
PubMed 31976811Hajiagha MN, Kafil HS. Efflux pumps and microbial biofilm formation. Infect Genet Evol. 2023 Aug;112:105459. doi: 10.1016/j.meegid.2023.105459. Epub 2023 Jun 2.
PubMed 37271271Ren J, Wang M, Zhou W, Liu Z. Efflux pumps as potential targets for biofilm inhibition. Front Microbiol. 2024 Feb 23;15:1315238. doi: 10.3389/fmicb.2024.1315238. eCollection 2024.
PubMed 38596384Soto SM. Role of efflux pumps in the antibiotic resistance of bacteria embedded in a biofilm. Virulence. 2013 Apr 1;4(3):223-9. doi: 10.4161/viru.23724. Epub 2013 Feb 4.
PubMed 23380871Habib MB, Shah NA, Amir A, Alghamdi HA, Tariq MH, Nisa K, Ammoun M. Decoding MexB efflux pump genes: structural, molecular, and phylogenetic analysis of multidrug-resistant and extensively drug-resistant Pseudomonas aeruginosa. Front Cell Infect Microbiol. 2025 Jan 21;14:1519737. doi: 10.3389/fcimb.2024.1519737. eCollection 2024.
PubMed 39906216
Study at a glance
From the registry record, last updated by the sponsor on 17 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Relationship Between mexB Efflux Pump Gene Expression, Efflux Pump Activity and Biofilm Formation in Multidrug Resistant Clinical Isolates of Pseudomonas Aeruginosa
- ClinicalTrials.gov ID
- NCT07469436
- Acronym / sponsor ID
- RBMEPGEEPAABFIMRCIOPA
- Conditions
- Pseudomonas Aeroginosa
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- Apr 2026 (estimated)
- Primary completion
- Dec 2027 (estimated)
- Study completion
- Jan 2028 (estimated)
- First posted
- 13 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
- Detection of expression level of mexB efflux pump gene in multidrug resistant clinical isolates of Pseudomonas aeruginosa by real time PCR(QRT-PCR).
- Phenotypic detection of efflux pump activity in multidrug resistant clinical isolates of Pseudomonas aeruginosa.
- Phenotypic detection of biofilm formation and its degree (strong-moderate-weak) in multidrug resistant clinical isolates of Pseudomonas aeruginosa.
- Relationship between expression level of mexB efflux pump gene and degree of biofilm formation in multidrug resistant clinical isolates of Pseudomonas aeruginosa.
Detailed description
Pseudomonas aeruginosa is an opportunistic gram-negative pathogen, causing life threatening nosocomial infections including respiratory system, urinary system and skin wounds (1). P. aeruginosa exhibits resistance to a range of antibiotic classes, including aminoglycosides, carbapenems, beta-lactams, quinolones, and cephalosporins (2). Frequent occurrence of drug resistance is due to many virulence factors in P. aeruginosa such as flagella, pili, lipopolysaccharides, secreted enzymes like DNase and lipase, toxins, and pigments as pyocyanin which play crucial roles in tissue damage and immune suppression. Multiple resistant mechanisms are developed by P. aeruginosa (3). Two prominent mechanisms, biofilm formation and efflux pump activity among other mechanisms, play an important role in persistence and antibiotic resistance (4). Biofilm formation produced by P. aeruginosa is a complex phenomenon that promotes antibiotic resistance and shields the pathogen from the host immune system. This results in severe clinical outcomes in critically ill patients (5). There are about 12 resistance-nodulation-division (RND) families of efflux pumps in P. aeruginosa. The mexAB-oprM multidrug efflux pump system of P. aeruginosa is involved in resistance (6). Efflux pumps play a role in biofilm formation by influencing Physical-chemical interactions, mobility, gene regulation, quorum sensing (QS), extracellular polymeric substances (EPS), and toxic compound extrusion (6)(7). It has been demonstrated that MexAB-OprM plays a role in the resistance of aztreonam, gentamicin, tetracycline and tobramycin in biofilm structures of P. aeruginosa (8). MexB is the most critical and specific gene for efflux activity within the MexAB-OprM system and contributes to antibiotic resistance in Pseudomonas aeruginosa (9).
Study design
- Observational model
- Cohort
- Time perspective
- Cross-sectional
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- Patients with multidrug resistant clinical isolates of Pseudomonas aeruginosa.
Key inclusion criteria (2 listed)
- Clinical isolates confirmed as Pseudomonas aeruginosa by microbiological testing.
- Isolates collected from different clinical specimens (e.g., wound swabs, sputum, urine, blood, and catheters).
Key exclusion criteria (3 listed)
- Bacterial species other than Pseudomonas aeruginosa.
- Repeated clinical isolates from the same patient.
- Repeated clinical specimens from different sources of the same patient.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Real time PCRClinical isolates of Pseudomonas aeruginosa will undergo RNA extraction followed by cDNA (complementary DNA) synthesis. Quantitative real-time PCR will be performed using specific primers for the mexB efflux pump gene, and SYBR Green will be used to quantify gene expression. Housekeeping genes (e.g., rpoD or 16S rRNA) will serve as internal controls. The procedure allows precise quantification of mexB expression levels in each isolate. | Genetic | – |
Primary outcome
Detection of mexB efflux pump gene expression level in multidrug resistant clinical isolates of Pseudomonas aeruginosa
Time frame: one year
molecular detection of mexB efflux pump gene expression level by real time PCR (QRT-PCR)
2 secondary outcomes
Detection of efflux pump activity in multidrug resistant clinical isolates of Pseudomonas aeruginosa
Time frame: one year
Detection of degree of biofilm formation (strong-moderate-weak) in multidrug resistant clinical isolates of Pseudomonas aeruginosa
Time frame: one year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Mar 2026.
- Background: PubMed 35302222Li XF, Shi HQ, Liang Y, Li J, Jiang B, Song GB. Interaction of biofilm and efflux pump in clinical isolates of carbapenem resistant P. aeruginosa. Eur Rev Med Pharmacol Sci. 2022 Mar;26(5):1729-1737. doi: 10.26355/eurrev_202203_28242.
- Background: PubMed 40599435Soltani Borchaloee A, Moosakazemi Mohammadi LS, Khosh Ravesh R, Allameh SF, Tabatabaie Poya FS, Fatehi MA. Prevalence of Biofilm and Efflux Pump Genes Expression by PCR and Antibiotic Resistance Pattern in Pseudomonas Aeruginosa. Arch Razi Inst. 2024 Dec 31;79(6):1281-1286. doi: 10.32592/ARI.2024.79.6.1281. eCollection 2024 Dec.
- Background: PubMed 35873152Liao C, Huang X, Wang Q, Yao D, Lu W. Virulence Factors of Pseudomonas Aeruginosa and Antivirulence Strategies to Combat Its Drug Resistance. Front Cell Infect Microbiol. 2022 Jul 6;12:926758. doi: 10.3389/fcimb.2022.926758. eCollection 2022.
- Background: PubMed 33531042Ugwuanyi FC, Ajayi A, Ojo DA, Adeleye AI, Smith SI. Evaluation of efflux pump activity and biofilm formation in multidrug resistant clinical isolates of Pseudomonas aeruginosa isolated from a Federal Medical Center in Nigeria. Ann Clin Microbiol Antimicrob. 2021 Feb 2;20(1):11. doi: 10.1186/s12941-021-00417-y.
- Background: PubMed 31976811Karballaei Mirzahosseini H, Hadadi-Fishani M, Morshedi K, Khaledi A. Meta-Analysis of Biofilm Formation, Antibiotic Resistance Pattern, and Biofilm-Related Genes in Pseudomonas aeruginosa Isolated from Clinical Samples. Microb Drug Resist. 2020 Jul;26(7):815-824. doi: 10.1089/mdr.2019.0274. Epub 2020 Jan 23.
- Background: PubMed 37271271Hajiagha MN, Kafil HS. Efflux pumps and microbial biofilm formation. Infect Genet Evol. 2023 Aug;112:105459. doi: 10.1016/j.meegid.2023.105459. Epub 2023 Jun 2.
- Background: PubMed 38596384Ren J, Wang M, Zhou W, Liu Z. Efflux pumps as potential targets for biofilm inhibition. Front Microbiol. 2024 Feb 23;15:1315238. doi: 10.3389/fmicb.2024.1315238. eCollection 2024.
- Background: PubMed 23380871Soto SM. Role of efflux pumps in the antibiotic resistance of bacteria embedded in a biofilm. Virulence. 2013 Apr 1;4(3):223-9. doi: 10.4161/viru.23724. Epub 2013 Feb 4.
- Background: PubMed 39906216Habib MB, Shah NA, Amir A, Alghamdi HA, Tariq MH, Nisa K, Ammoun M. Decoding MexB efflux pump genes: structural, molecular, and phylogenetic analysis of multidrug-resistant and extensively drug-resistant Pseudomonas aeruginosa. Front Cell Infect Microbiol. 2025 Jan 21;14:1519737. doi: 10.3389/fcimb.2024.1519737. eCollection 2024.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Assiut University study director
Assiut University
Questions about this trial
What is this clinical trial studying?
An observational study of Pseudomonas Aeroginosa, run by Assiut University.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 17 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Rehab AM Omran (01025113833, remy25.1994rn@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Detection of mexB efflux pump gene expression level in multidrug resistant clinical isolates of Pseudomonas aeruginosa (time frame: one year). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07469436, which also lists 9 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Mar 2026.