caa a22 4500 605504776 CHVBK 20210128100618.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s00253-015-6868-7 doi (NATIONALLICENCE)springer-10.1007/s00253-015-6868-7 Involvement of quorum sensing genes in biofilm development and degradation of polycyclic aromatic hydrocarbons by a marine bacterium Pseudomonas aeruginosa N6P6 [Elektronische Daten] [Neelam Mangwani, Supriya Kumari, Surajit Das] Biofilm-forming and acyl homoserine lactone (AHL) synthase-positive Pseudomonas aeruginosa N6P6 was isolated from seawater after selective enrichment with two polycyclic aromatic hydrocarbons (PAHs), viz. phenanthrene and pyrene. AHL synthesis was detected qualitatively using bioreporter strains. This marine bacterium putatively synthesized N-(3-oxododecanoyl)-l-homoserine lactone and N-butyryl-l-homoserine lactone, which were identified by TLC, GC-MS, and HPLC. Two quorum sensing (QS) genes coding for AHL synthase, i.e., lasI and rhlI, were identified in the bacterium. lasI and rhlI gene expression was studied during biofilm mode of growth at different phases using quantitative real-time PCR (qRT-PCR). The expression of lasI increased with increase in biofilm growth. In contrast, the expression of rhlI decreased during log phase of biofilm growth. The changes in lasI/rhlI expression level had significant effects (P<0.05) on biofilm architecture and subsequent PAH degradation rate. Degradation of phenanthrene and pyrene by P. aeruginosa N6P6 was affected by biofilm growth and lasI expression. The respective phenanthrene degradation for 15, 24, 48, and 72h old biofilm after 7days was 21.5, 54.2, 85.6, and 85.7%. However, the corresponding pyrene degradation was 15, 18.28, 47.56, and 46.48%, respectively, after 7days. A significant positive correlation (P<0.05) was observed between lasI expression and PAHs degradation. However, in the presence of tannic acid, a QS inhibitor (QSI), PAHs degradation, biofilm formation, and pyocyanin production reduced significantly which confirmed the pivotal role of QS in biodegradation of PAHs. The findings suggest that AHLs play a pivotal role during biofilm development and subsequent bioremediation of PAHs. Springer-Verlag Berlin Heidelberg, 2015 Acyl homoserine lactones nationallicence PAHs nationallicence lasI nationallicence rhlI nationallicence Biofilm nationallicence Gene expression nationallicence Biodegradation nationallicence Tannic acid nationallicence Mangwani Neelam Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, 769 008, Rourkela, Odisha, India aut Kumari Supriya Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, 769 008, Rourkela, Odisha, India aut Das Surajit Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, 769 008, Rourkela, Odisha, India aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/23(2015-12-01), 10283-10297 0175-7598 99:23<10283 2015 99 253 https://doi.org/10.1007/s00253-015-6868-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-015-6868-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Mangwani Neelam Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, 769 008, Rourkela, Odisha, India aut NATIONALLICENCE 700 1- Kumari Supriya Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, 769 008, Rourkela, Odisha, India aut NATIONALLICENCE 700 1- Das Surajit Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, 769 008, Rourkela, Odisha, India aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/23(2015-12-01), 10283-10297 0175-7598 99:23<10283 2015 99 253