All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.

Genetic expression of pobA and fabHB in Bacillus licheniformis M2-7 in the presence of benzo[a]pyrene

Author(s): Augusto Rojas-Aparicio, José A. Hernández-Eligio, Jeiry Toribio-Jiménez, Miguel Á. Rodríguez-Barrera, Mildred Castellanos-Escamilla and Yanet Romero-Ramírez

Bacillus licheniformis M2-7 is a heat-resistant bacterium able to biotransform polycyclic aromatic hydrocarbons. It can transform a wide range of these compounds as naphthalene, phenanthrene, pyrene and benzo[a]pyrene. Benzo[a]pyrene is a polycyclic aromatic hydrocarbon of high molecular weight considered as potentially toxic and carcinogenic for humans. Aiming to discover the genes involved in the biotransformation of benzo[a]pyrene, we made a B. licheniformis M2-7 genomic library in E. coli. We isolated two E. coli strains that were able to grow in minimal salt medium supplemented with benzo[a]pyrene. From the analysis of the DNA fragments in the clones H23 and H38, we identified open reading frames coding for 5 possible genes, among them pobA and fabHB, which products are the enzymes 4-hydroxybenzoate 3-monooxygenase and the ketoacyl-ACP synthase III, respectively. To evaluate the role of these genes in the metabolism of benzo[a]pyrene in B. licheniformis M2-7, we estimated their relative expression through reverse transcription quantitative PCR. Finally, we observed that the genes pobA and fabHB were overexpressed after 3 h under induction with benzo[a]pyrene, suggesting that this strain could use these genes during the metabolism of this PAH, plus it does it in a faster time than that reported for other bacterial genera


Stay informed on our latest news!