%0 Journal Article %T Construction and Characterization of a Lux-Marked Phenanthrene Degrading Bacterium %J Iranian Journal of Biotechnology %I National Institute of Genetic Engineering and Biotechnology of Iran %Z 1728-3043 %A Mashreghi, Mansour %A Prosser, James I %D 2004 %\ 10/01/2004 %V 2 %N 4 %P 243-249 %! Construction and Characterization of a Lux-Marked Phenanthrene Degrading Bacterium %K Lux AB gene %K Phenanthrene %K Molecular Marker and Degradative bacteria %R %X Construction of a luminescent microbial biosensor as a sensitive and rapid biotechnological tool for monitoringsurvival and activity of genetically engineered microorganisms (GEMs) in the contaminated environment hasbeen the main focus of this study. Four rifampicin resistant phenanthrene-degrading bacteria viz.,Commamonas testosteroni GZ38A, C. testosteroni GZ39, Pseudomonas putida GZ44 and P. stutzeri P16were made using gradient plate techniques. All resistant strains were transformed with the plasmid harboringthe mini-Tn5-tet transposon cassette, containing the luxAB genes to confer stability. C. testosteroniGZ38A and P. stutzeri P16 were successfully luxmarked in this manner. It was found that lux-markedstrains of C. testosteroni GZ38A were not able to degrade phenanthrene. Although the maximum growthrate of lux-marked strain was significantly lower (P < 0.05) than that of the wild type P. stutzeri P16, the P.stutzeri P16-luxAB4 was selected because it has the following criteria: the stability of expression of tetresistance over 180 generations, phenanthrene - degradability and high level of luminescence light outputin the absence and presence of phenanthrene. The addition of 1 litter (0.5 % v/v) n-decyl aldehydeproduced consistently high levels of luminescence at various stages of selected strain. Results clearly indicatedthat lux-marked strain was appropriately constructed and it is a novel biodegradative luminescentbiosensor which enables us to monitor the fate of a phenathrene bacterial degrader genetically or nongenetically made within a polluted environment. %U https://www.ijbiotech.com/article_6916_9e28f71a1e77eb471886d7558b3d789f.pdf