Study of Detection of lasB gene and its Phenotypic Expression in Pseudomonas aeruginosa Obtained From Various Clinical Samples

  • Jagannath D. Andhale Associate Professor, Department of Microbiology, Ananta Institute of Medical Sciences & Research Center, Rajsamand, Rajasthan, India-313202.
  • R.N Misra Professor & Head, Department of Microbiology, Dr.D.Y.Patil Medical College, Hospital and Research Center (Dr.D.Y.Patil Vidyapeeth) Pune, India-411018
Keywords: P.aeruginosa, lasB, elastase B, Polymerase chain reaction.


Background: Pseudomonas aeruginosa is amongst the top listed pathogens responsible for health care related infection and the third most common co-infecting pathogen among COVID-19 patients. P.aeruginosa can affect immunocompromised patients. A major problem in infections caused by P.aeruginosa is high and multi-drug resistance to antibiotics commonly used to treat the patients. P.aeruginosa produces cellular and extracellular virulent factors.The elastase enzyme encoded by lasB gene is a major virulence factor secreted by P.aeruginosa that contributes in pathogenicity. In India, few researchers have focussed on virulence lasB gene and its allied virulence factor elastase B in P.aeruginosa. Therefore, this study was planned to study detection and phenotypic expression of lasB genes in P. aeruginosa clinical strains.

Materials and methods: This research study included 30 strains of P. aeruginosa obtained from various clinical samples. Screening of elastase B production was studied on nutrient agar media containing 1% elastin in 0.1 M tris buffer (pH 8.0), 0.04 M CaCl2, and 0.03 M tris buffer (pH.8.0) and geneslasBwere detected by polymerase chain reactions and gel electrophoresis technique.

 Results:  Polymerase chain reaction amplification results showed presence of lasB genes in 23 (76.67%) out of 30 P.aeruginosa strains and 18 (60%) of the isolates showed elastase B production.

Conclusion: Gene lasB in P. aeruginosa is one of the major virulent factors and contributes in causation of disease. It is concluded that lasB gene can be a notable virulent factor shown by presence of 76.67% and expressed phenotypically by 60% of P. aeruginosa strains. The specified key role of lasB virulent gene in the development of disease would help in determining idea of the prognosis of infections caused by P.aeruginosa and understanding successful treatment plan and designing ideal vaccine against the prevention of P.aeruginosa infection.


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How to Cite
Andhale JD, Misra R. Study of Detection of lasB gene and its Phenotypic Expression in Pseudomonas aeruginosa Obtained From Various Clinical Samples. Int Arch BioMed Clin Res [Internet]. 2021Dec.31 [cited 2022Jan.27];7(4):MB1-MB4. Available from: