抄録
Mercurials have been released into the environment by geological or anthropogenic activities. Organomercurial compounds such as methylmercury are known as toxic compounds. Therefore, organomercurials should be monitored to keep clean environments. However, chemical species of organomercurials are not easily detected separately or individually.
In this study, we tried to detect organomercurial compounds by using a bacterial gene-expression system. A series of mer operon-luciferase (mer-lux) transcriptional fusion plasmids (pHYΔB3Lux and pHYB3Lux) was constructed to evaluate the gene expression system with a new organomercury lyase gene merB3 from Bacillus megaterium MB1. A plasmid (pGR1A) encoding mer operon genes from O/PmerR1 to merA isolated from B. megaterium MB1 was used as a transacting gene expression vector with the mer-lux transcriptional fusion plasmids into a same host bacterial cell. The transformants that carry a set of two plasmids (pHYΔB3Lux+pGR1A or pHYB3Lux+pGR1A), respectively) were used for detection of organomercurials. The experimental results showed that the transformant with pHYΔB3Lux+pGR1A responded to only mercury chloride (MC). On the other hand, the transformant with pHYB3Lux+pGR1A responded and detected MC and the all organomercurials tested in the study. Therefore, the bacterial strain which possess a gene expression system of mer-lux transcriptional fusion was useful to detect organomercurials with distinction from inorganic mercury.
