Related Experiment Video
Updated: Nov 22, 2025
Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Antimicrobial susceptibility pattern of Stenotrophomonas species isolated from Mexico
Temidayo O Elufisan1,2, Isabel Cristina Rodriguez Luna1, Omotayo O Oyedara3
1Instituto Politécnico Nacional, Centro de Biotecnología Genómica, Reynosa, Tamaulipas 88710, México.
Background:
Stenotrophomonas species are multi-resistant bacteria with ability to cause opportunistic infections.
Objective:
We isolated 45 Stenotrophomonas species from soil, sewage and the clinic with the aim of investigating their susceptibility to commonly used antimicrobial agents.
Methodology:
The identities of isolates were confirmed with 16S rRNA gene sequence and MALDI-TOF analysis. Anti-microbial resistance, biofilm production and clonal diversity were also evaluated. The minimum inhibitory concentration technique as described by Clinical & Laboratory Standards Institute: CLSI Guidelines (CLSI) was employed for the evaluation of isolate susceptibility to antibiotics.
Result:
Forty-five Stenotrophomonas species which include 36 environmental strains and 9 clinical strains of S. maltophilia were considered in this study. 32 (88.9 %) environmental strains were identified to be S. maltophilia, 2 (5.6 %) were Stenotrophomonas nitritireducens, and 2 (5.6 %) cluster as Stenotrophomonas spp. Stenotrophomonas isolates were resistant to at least six of the antibiotics tested, including Trimethoprim/Sulfamethoxazole (SXT).
Conclusion:
Environmental isolates from this study were resistant to SXT which is commonly used for the treatment of S. maltophilia infections. This informs the need for good public hygiene as the environment could be a reservoir of multi-resistant bacteria. It also buttresses the importance of surveillance study in the management of bacterial resistance.
Insights
Environmental Stenotrophomonas species, including S. maltophilia, show resistance to Trimethoprim/Sulfamethoxazole (SXT). This highlights the environment as a reservoir for multi-resistant bacteria, necessitating public hygiene and surveillance.
Area of Science:
- Microbiology
- Environmental Science
- Infectious Diseases
Background:
- Stenotrophomonas species are opportunistic pathogens known for multi-drug resistance.
- Understanding the environmental prevalence and resistance patterns of Stenotrophomonas is crucial for public health.
Purpose of the Study:
- To investigate the antimicrobial susceptibility of Stenotrophomonas isolates from environmental and clinical sources.
- To identify Stenotrophomonas species and evaluate their resistance profiles to common antibiotics.
Main Methods:
- Isolates were identified using 16S rRNA gene sequencing and MALDI-TOF analysis.
- Antimicrobial susceptibility testing was performed using the minimum inhibitory concentration (MIC) method according to CLSI guidelines.
- Biofilm production and clonal diversity were also assessed.
Main Results:
- Forty-five Stenotrophomonas isolates were analyzed, comprising 36 environmental and 9 clinical strains, predominantly S. maltophilia.
- A significant proportion of environmental Stenotrophomonas isolates exhibited resistance to at least six tested antibiotics, including Trimethoprim/Sulfamethoxazole (SXT).
- Identified species included S. maltophilia, Stenotrophomonas nitritireducens, and other Stenotrophomonas spp.
Conclusions:
- Environmental Stenotrophomonas isolates demonstrate resistance to SXT, an antibiotic commonly used for S. maltophilia infections.
- The environment serves as a potential reservoir for multi-resistant bacteria, emphasizing the need for stringent public hygiene measures.
- Continuous surveillance studies are vital for effective management of antimicrobial resistance in Stenotrophomonas species.
