Investigation of virulence factors and genes associated with biofilm and protease in Stenotrophomonas maltophilia isolates in Bushehr, Iran
Abstract
Background and Objectives: This study aimed to investigate the virulence factors and genes associated with biofilm and protease in Stenotrophomonas maltophilia in Bushehr, Iran.
Materials and Methods: Eighty-seven S. maltophilia isolates (67 clinical and 20 environmental isolates) were studied. The isolates were assessed for the production of virulence factors including several enzymes and biofilm. To detect rmlA, rpfF, spgM, smf-1, StmPr1 868 bp, StmPr1 1621 bp, and StmPr2 genes, PCR and sequencing were performed.
Results: All isolates (100%) produced DNase, hemolysin, protease, lipase, and hyaluronidase. Seventy-eight (89.7%) isolates were gelatinase producers, and 85 (97.7%) isolates were lecithinase producers. All isolates were biofilm producers: 79 (90.8%) isolates produced strong biofilm, 5 (5.7%) isolates produced moderate biofilm, and 3 (3.5%) isolates produced weak biofilm. The frequency of smf-1, rmlA, rpfF, and spgM was 93.1%, 86.2%, 26.4%, and 59.8%, respectively. The frequency of protease genes including StmPr1 868 bp, StmPr1 1621 bp, and StmPr2 was 12.6%, 41.4%, and 18.4%, respectively.
Conclusion: Our findings revealed a high frequency of isolates that produce DNase, hemolysin, protease, gelatinase, lipase, lecithinase, hyaluronidase, and biofilm. All isolates that harbored spgM or rpfF or both genes were strong biofilm producers. Notably, the presence of isolates that lacked spgM and rpfF genes but produced strong biofilm indicates that in addition to these two genes, other genes or factors may play a role in the production of strong biofilm. Based on this research, S. maltophilia in our area possesses the capability to produce several factors that could play roles in pathogenicity.
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2. Thomas R, Hamat RA, Neela V. Extracellular enzyme profiling of Stenotrophomonas maltophilia clinical isolates. Virulence 2014; 5: 326-330.
3. de Oliveira Garcia D, Timenetsky J, Martinez MB, Francisco W, Sinto SI, Yanaguita RM. Proteases (caseinase and elastase), hemolysins, adhesion and susceptibility to antimicrobials of Stenotrophomonas maltophilia isolates obtained from clinical specimens. Braz J Microbiol 2002; 33: 157-162.
4. Brooke JS, Di Bonaventura G, Berg G, Martinez J-L. Editorial: A multidisciplinary look at Stenotrophomonas maltophilia: An emerging multi-drug-resistant global opportunistic pathogen. Front Microbiol 2017; 8: 1511.
5. Hanes SD, Demirkan K, Tolley E, Boucher BA, Croce MA, Wood GC, et al. Risk factors for late-onset nosocomial pneumonia caused by Stenotrophomonas maltophilia in critically ill trauma patients. Clin Infect Dis 2002; 35: 228-235.
6. Vidal F, Mensa J, Almela M, Olona M, Martinez JA, Marco F, et al. Bacteraemia in adults due to glucose non‐fermentative Gram‐negative bacilli other than P. aeruginosa. QJM 2003; 96: 227-234.
7. Asaadi H, Tajbakhsh S, Naeimi B, Gharibi O. Identification of Stenotrophomonas maltophilia in blood cultures by fluorescence in situ hybridization. Infect Dis Clin Pract 2021; 29(6): e376-e379.
8. Bostanghadiri N, Ghalavand Z, Fallah F, Yadegar A, Ardebili A, Tarashi S, et al. Characterization of phenotypic and genotypic diversity of Stenotrophomonas maltophilia strains isolated from selected hospitals in Iran. Front Microbiol 2019; 10: 1191.
9. Passerini de Rossi B, Calenda M, Vay C, Franco M. Biofilm formation by Stenotrophomonas maltophilia isolates from device-associated nosocomial infections. Rev Argent Microbiol 2007; 39: 204-212.
10. Huang TP, Somers EB, Wong AC. Differential biofilm formation and motility associated with lipopolysaccharide/exopolysaccharide-coupled biosynthetic genes in Stenotrophomonas maltophilia. J Bacteriol 2006; 188: 3116-3120.
11. Zhuo C, Zhao Q-y, Xiao S-n. The impact of spgM, rpfF, rmlA gene distribution on biofilm formation in Stenotrophomonas maltophilia. PloS One 2014; 9(10): e108409.
12. Trifonova A, Strateva T. Stenotrophomonas maltophilia – a low-grade pathogen with numerous virulence factors. Infect Dis (Lond) 2019; 51: 168-178.
13. Kim H-R, Lee D, Eom Y-B. Anti-biofilm and anti-virulence efficacy of celastrol against Stenotrophomonas maltophilia. Int J Med Sci 2018; 15: 617-627.
14. Gallo SW, Ramos PL, Ferreira CA, Oliveira SD. A specific polymerase chain reaction method to identify Stenotrophomonas maltophilia. Mem Inst Oswaldo Cruz 2013; 108: 390-391.
15. Kalaivani R, Jenitha JP, Seetha KS. Clinical isolates of Klebsiella pneumoniae and its virulence factors from a tertiary care hospital. Indian J Microbiol Res 2019; 6: 109-112.
16. Cevahir N, Demir M, Kaleli I, Gurbuz M, Tikvesli S. Evaluation of biofilm production, gelatinase activity, and mannose-resistant hemagglutination in Acinetobacter baumannii strains. J Microbiol Immunol Infect 2008; 41: 513-518.
17. Visan D-C, Oprea E, Radulescu V, Voiculescu I, Biris I-A, Cotar AI, et al. Original contributions to the chemical composition, microbicidal, virulence-arresting and antibiotic-enhancing activity of essential oils from four coniferous species. Pharmaceuticals (Basel) 2021; 14: 1159.
18. Tille PM (2013). Bailey & Scott’s Diagnostic Microbiology. Elsevier. 13 th ed. https://shop.elsevier.com/books/bailey-and-scotts-diagnostic-microbiology/tille/978-0-323-08330-0
19. Speck S, Höner OP, Wachter B, Fickel J. Characterization of Streptococcus equi subsp. ruminatorum isolated from spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli), and identification of a M-like protein (SrM) encoding gene. Vet Microbiol 2008; 128: 148-159.
20. Maasjost J, Lüschow D, Kleine A, Hafez HM, Mühldorfer K. Presence of virulence genes in Enterococcus species isolated from meat turkeys in Germany does not correlate with chicken embryo Lethality. Biomed Res Int 2019; 2019: 6147695.
21. Stepanović S, Vuković D, Hola V, Di Bonaventura G, Djukić S, Ćirković I, et al. Quantification of biofilm in microtiter plates: overview of testing conditions and practical recommendations for assessment of biofilm production by staphylococci. APMIS 2007; 115: 891-899.
22. Mirbag HH, Tajbakhsh S, Askari A, Yousefi F. Comparison of virulence factors between ESBL and non-ESBL producing Klebsiella pneumoniae isolates. Iran J Microbiol 2024; 16: 39-48.
23. Nicoletti M, Iacobino A, Prosseda G, Fiscarelli E, Zarrilli R, De Carolis E, et al. Stenotrophomonas maltophilia strains from cystic fibrosis patients: genomic variability and molecular characterization of some virulence determinants. Int J Med Microbiol 2011; 301: 34-43.
24. Foster NF, Harnett GB, Riley TV, Chang BJ. Cross-reaction of Stenotrophomonas and Xanthomonas species in a 23S rRNA gene-directed PCR for detection of S. maltophilia. J Clin Microbiol 2008; 46: 4111-4113.
25. ElBaradei A, Yakout MA. Stenotrophomonas maltophilia: Genotypic characterization of virulence genes and the effect of ascorbic acid on biofilm formation. Curr Microbiol 2022; 79: 180.
26. Alcaraz E, Garcia C, Papalia M, Vay C, Friedman L, Passerini de Rossi B. Stenotrophomonas maltophilia isolated from patients exposed to invasive devices in a university hospital in Argentina: molecular typing, susceptibility and detection of potential virulence factors. J Med Microbiol 2018; 67: 992-1002.
27. Azimi A, Aslanimehr M, Yaseri M, Shadkam M, Douraghi M. Distribution of smf-1, rmlA, spgM and rpfF genes among Stenotrophomonas maltophilia isolates in relation to biofilm-forming capacity. J Glob Antimicrob Resist 2020; 23: 321-326.
28. Flores-Treviño S, Gutierrez-Ferman JL, Morfín-Otero R, Rodríguez-Noriega E, Estrada-Rivadeneyra D, Rivas-Morales C, et al. Stenotrophomonas maltophilia in Mexico: antimicrobial resistance, biofilm formation and clonal diversity. J Med Microbiol 2014; 63: 1524-1530.
29. Pompilio A, Piccolomini R, Picciani C, D'Antonio D, Savini V, Di Bonaventura G. Factors associated with adherence to and biofilm formation on polystyrene by Stenotrophomonas maltophilia: the role of cell surface hydrophobicity and motility. FEMS Microbiol lett 2008; 287: 41-47.
30. Gallo SW, Figueiredo TP, Bessa MC, Pagnussatti VE, Ferreira CA, Oliveira SD. Isolation and characterization of Stenotrophomonas maltophilia isolates from a Brazilian hospital. Microb Drug Resist 2016; 22: 688-695.
31. Flores-Treviño S, Bocanegra-Ibarias P, Camacho-Ortiz A, Morfín-Otero R, Salazar-Sesatty HA, Garza-González E. Stenotrophomonas maltophilia biofilm: its role in infectious diseases. Expert Rev Anti Infect Ther 2019; 17: 877-893.
32. de Oliveira‐Garcia D, Dall’Agnol M, Rosales M, Azzuz AC, Alcántara N, Martinez MB, et al. Fimbriae and adherence of Stenotrophomonas maltophilia to epithelial cells and to abiotic surfaces. Cell Microbiol 2003; 5: 625-636.
33. Pompilio A, Pomponio S, Crocetta V, Gherardi G, Verginelli F, Fiscarelli E, et al. Phenotypic and genotypic characterization of Stenotrophomonas maltophilia isolates from patients with cystic fibrosis: Genome diversity, biofilm formation, and virulence. BMC Microbiol 2011; 11: 159.
34. Duan Z, Qin J, Li C, Ying C. Clinical and molecular epidemiology of Stenotrophomonas maltophilia in pediatric patients from a Chinese teaching hospital. Front Cell Infect Microbiol 2020; 10: 411.
2. Thomas R, Hamat RA, Neela V. Extracellular enzyme profiling of Stenotrophomonas maltophilia clinical isolates. Virulence 2014; 5: 326-330.
3. de Oliveira Garcia D, Timenetsky J, Martinez MB, Francisco W, Sinto SI, Yanaguita RM. Proteases (caseinase and elastase), hemolysins, adhesion and susceptibility to antimicrobials of Stenotrophomonas maltophilia isolates obtained from clinical specimens. Braz J Microbiol 2002; 33: 157-162.
4. Brooke JS, Di Bonaventura G, Berg G, Martinez J-L. Editorial: A multidisciplinary look at Stenotrophomonas maltophilia: An emerging multi-drug-resistant global opportunistic pathogen. Front Microbiol 2017; 8: 1511.
5. Hanes SD, Demirkan K, Tolley E, Boucher BA, Croce MA, Wood GC, et al. Risk factors for late-onset nosocomial pneumonia caused by Stenotrophomonas maltophilia in critically ill trauma patients. Clin Infect Dis 2002; 35: 228-235.
6. Vidal F, Mensa J, Almela M, Olona M, Martinez JA, Marco F, et al. Bacteraemia in adults due to glucose non‐fermentative Gram‐negative bacilli other than P. aeruginosa. QJM 2003; 96: 227-234.
7. Asaadi H, Tajbakhsh S, Naeimi B, Gharibi O. Identification of Stenotrophomonas maltophilia in blood cultures by fluorescence in situ hybridization. Infect Dis Clin Pract 2021; 29(6): e376-e379.
8. Bostanghadiri N, Ghalavand Z, Fallah F, Yadegar A, Ardebili A, Tarashi S, et al. Characterization of phenotypic and genotypic diversity of Stenotrophomonas maltophilia strains isolated from selected hospitals in Iran. Front Microbiol 2019; 10: 1191.
9. Passerini de Rossi B, Calenda M, Vay C, Franco M. Biofilm formation by Stenotrophomonas maltophilia isolates from device-associated nosocomial infections. Rev Argent Microbiol 2007; 39: 204-212.
10. Huang TP, Somers EB, Wong AC. Differential biofilm formation and motility associated with lipopolysaccharide/exopolysaccharide-coupled biosynthetic genes in Stenotrophomonas maltophilia. J Bacteriol 2006; 188: 3116-3120.
11. Zhuo C, Zhao Q-y, Xiao S-n. The impact of spgM, rpfF, rmlA gene distribution on biofilm formation in Stenotrophomonas maltophilia. PloS One 2014; 9(10): e108409.
12. Trifonova A, Strateva T. Stenotrophomonas maltophilia – a low-grade pathogen with numerous virulence factors. Infect Dis (Lond) 2019; 51: 168-178.
13. Kim H-R, Lee D, Eom Y-B. Anti-biofilm and anti-virulence efficacy of celastrol against Stenotrophomonas maltophilia. Int J Med Sci 2018; 15: 617-627.
14. Gallo SW, Ramos PL, Ferreira CA, Oliveira SD. A specific polymerase chain reaction method to identify Stenotrophomonas maltophilia. Mem Inst Oswaldo Cruz 2013; 108: 390-391.
15. Kalaivani R, Jenitha JP, Seetha KS. Clinical isolates of Klebsiella pneumoniae and its virulence factors from a tertiary care hospital. Indian J Microbiol Res 2019; 6: 109-112.
16. Cevahir N, Demir M, Kaleli I, Gurbuz M, Tikvesli S. Evaluation of biofilm production, gelatinase activity, and mannose-resistant hemagglutination in Acinetobacter baumannii strains. J Microbiol Immunol Infect 2008; 41: 513-518.
17. Visan D-C, Oprea E, Radulescu V, Voiculescu I, Biris I-A, Cotar AI, et al. Original contributions to the chemical composition, microbicidal, virulence-arresting and antibiotic-enhancing activity of essential oils from four coniferous species. Pharmaceuticals (Basel) 2021; 14: 1159.
18. Tille PM (2013). Bailey & Scott’s Diagnostic Microbiology. Elsevier. 13 th ed. https://shop.elsevier.com/books/bailey-and-scotts-diagnostic-microbiology/tille/978-0-323-08330-0
19. Speck S, Höner OP, Wachter B, Fickel J. Characterization of Streptococcus equi subsp. ruminatorum isolated from spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli), and identification of a M-like protein (SrM) encoding gene. Vet Microbiol 2008; 128: 148-159.
20. Maasjost J, Lüschow D, Kleine A, Hafez HM, Mühldorfer K. Presence of virulence genes in Enterococcus species isolated from meat turkeys in Germany does not correlate with chicken embryo Lethality. Biomed Res Int 2019; 2019: 6147695.
21. Stepanović S, Vuković D, Hola V, Di Bonaventura G, Djukić S, Ćirković I, et al. Quantification of biofilm in microtiter plates: overview of testing conditions and practical recommendations for assessment of biofilm production by staphylococci. APMIS 2007; 115: 891-899.
22. Mirbag HH, Tajbakhsh S, Askari A, Yousefi F. Comparison of virulence factors between ESBL and non-ESBL producing Klebsiella pneumoniae isolates. Iran J Microbiol 2024; 16: 39-48.
23. Nicoletti M, Iacobino A, Prosseda G, Fiscarelli E, Zarrilli R, De Carolis E, et al. Stenotrophomonas maltophilia strains from cystic fibrosis patients: genomic variability and molecular characterization of some virulence determinants. Int J Med Microbiol 2011; 301: 34-43.
24. Foster NF, Harnett GB, Riley TV, Chang BJ. Cross-reaction of Stenotrophomonas and Xanthomonas species in a 23S rRNA gene-directed PCR for detection of S. maltophilia. J Clin Microbiol 2008; 46: 4111-4113.
25. ElBaradei A, Yakout MA. Stenotrophomonas maltophilia: Genotypic characterization of virulence genes and the effect of ascorbic acid on biofilm formation. Curr Microbiol 2022; 79: 180.
26. Alcaraz E, Garcia C, Papalia M, Vay C, Friedman L, Passerini de Rossi B. Stenotrophomonas maltophilia isolated from patients exposed to invasive devices in a university hospital in Argentina: molecular typing, susceptibility and detection of potential virulence factors. J Med Microbiol 2018; 67: 992-1002.
27. Azimi A, Aslanimehr M, Yaseri M, Shadkam M, Douraghi M. Distribution of smf-1, rmlA, spgM and rpfF genes among Stenotrophomonas maltophilia isolates in relation to biofilm-forming capacity. J Glob Antimicrob Resist 2020; 23: 321-326.
28. Flores-Treviño S, Gutierrez-Ferman JL, Morfín-Otero R, Rodríguez-Noriega E, Estrada-Rivadeneyra D, Rivas-Morales C, et al. Stenotrophomonas maltophilia in Mexico: antimicrobial resistance, biofilm formation and clonal diversity. J Med Microbiol 2014; 63: 1524-1530.
29. Pompilio A, Piccolomini R, Picciani C, D'Antonio D, Savini V, Di Bonaventura G. Factors associated with adherence to and biofilm formation on polystyrene by Stenotrophomonas maltophilia: the role of cell surface hydrophobicity and motility. FEMS Microbiol lett 2008; 287: 41-47.
30. Gallo SW, Figueiredo TP, Bessa MC, Pagnussatti VE, Ferreira CA, Oliveira SD. Isolation and characterization of Stenotrophomonas maltophilia isolates from a Brazilian hospital. Microb Drug Resist 2016; 22: 688-695.
31. Flores-Treviño S, Bocanegra-Ibarias P, Camacho-Ortiz A, Morfín-Otero R, Salazar-Sesatty HA, Garza-González E. Stenotrophomonas maltophilia biofilm: its role in infectious diseases. Expert Rev Anti Infect Ther 2019; 17: 877-893.
32. de Oliveira‐Garcia D, Dall’Agnol M, Rosales M, Azzuz AC, Alcántara N, Martinez MB, et al. Fimbriae and adherence of Stenotrophomonas maltophilia to epithelial cells and to abiotic surfaces. Cell Microbiol 2003; 5: 625-636.
33. Pompilio A, Pomponio S, Crocetta V, Gherardi G, Verginelli F, Fiscarelli E, et al. Phenotypic and genotypic characterization of Stenotrophomonas maltophilia isolates from patients with cystic fibrosis: Genome diversity, biofilm formation, and virulence. BMC Microbiol 2011; 11: 159.
34. Duan Z, Qin J, Li C, Ying C. Clinical and molecular epidemiology of Stenotrophomonas maltophilia in pediatric patients from a Chinese teaching hospital. Front Cell Infect Microbiol 2020; 10: 411.
| Files | ||
| Issue | Vol 17 No 4 (2025) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/ijm.v17i4.19229 | |
| Keywords | ||
| Stenotrophomonas maltophilia Biofilm Virulence Pathogenicity | ||
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How to Cite
1.
Shadvar N, Yousefi F, Barazesh A, Tajbakhsh S. Investigation of virulence factors and genes associated with biofilm and protease in Stenotrophomonas maltophilia isolates in Bushehr, Iran. Iran J Microbiol. 2025;17(4):559-568.
