TY - JOUR
T1 - Metabolite production in degradation of pyrene alone or in a mixture with another polycyclic aromatic hydrocarbon by Mycobacterium sp.
AU - Zhong, Yin
AU - Luan, Tiangang
AU - Zhou, Hongwei
AU - Lan, Chongyu
AU - Tam, Nora Fung Yee
PY - 2006/11
Y1 - 2006/11
N2 - Degradation of pyrene (PYR) alone and in the presence of phenanthrene or fluoranthene by Mycobacterium sp. strain A1-PYR isolated from mangrove sediments was investigated. When PYR was the only polycyclic aromatic hydrocarbon compound and the sole carbon source, only 33% of the added PYR was slowly degraded during 7 d of incubation. Seven metabolites were obtained, including four-ring metabolites (monohydroxypyrene and three different dihydroxypyrenes) and three-ring metabolites (dihydroxyphenanthrene, 4-phenanthrene-carboxylic acid, and 4-phenanthrol), of which more four-ring metabolites accumulated compared with three-ring metabolites. To our knowledge, this is the first report in which PYR was initially attacked by Mycobacterium sp. to form three different dihydroxypyrenes. Pyrene degradation was significantly stimulated when mixed with phenanthrene or fluoranthene. In the presence of fluoranthene, PYR was rapidly degraded (up to 57%), and significant amounts of dihydroxypyrene were formed within 3 d of incubation, followed by a period of minimal PYR degradation from 3 to 7 d with disappearance of four-ring metabolites and accumulation of three-ring metabolites. In contrast, PYR was removed completely, and little evidence of metabolites was detected in the presence of phenanthrene. These results showed that PYR was degraded to a larger extent when mixed with another polycyclic aromatic hydrocarbon concomitant with a higher turnover of PYR metabolites. The induction of complex enzyme systems and increase in biomass possibly affected the transformation of PYR metabolites in the mixture with phenanthrene or fluoranthene.
AB - Degradation of pyrene (PYR) alone and in the presence of phenanthrene or fluoranthene by Mycobacterium sp. strain A1-PYR isolated from mangrove sediments was investigated. When PYR was the only polycyclic aromatic hydrocarbon compound and the sole carbon source, only 33% of the added PYR was slowly degraded during 7 d of incubation. Seven metabolites were obtained, including four-ring metabolites (monohydroxypyrene and three different dihydroxypyrenes) and three-ring metabolites (dihydroxyphenanthrene, 4-phenanthrene-carboxylic acid, and 4-phenanthrol), of which more four-ring metabolites accumulated compared with three-ring metabolites. To our knowledge, this is the first report in which PYR was initially attacked by Mycobacterium sp. to form three different dihydroxypyrenes. Pyrene degradation was significantly stimulated when mixed with phenanthrene or fluoranthene. In the presence of fluoranthene, PYR was rapidly degraded (up to 57%), and significant amounts of dihydroxypyrene were formed within 3 d of incubation, followed by a period of minimal PYR degradation from 3 to 7 d with disappearance of four-ring metabolites and accumulation of three-ring metabolites. In contrast, PYR was removed completely, and little evidence of metabolites was detected in the presence of phenanthrene. These results showed that PYR was degraded to a larger extent when mixed with another polycyclic aromatic hydrocarbon concomitant with a higher turnover of PYR metabolites. The induction of complex enzyme systems and increase in biomass possibly affected the transformation of PYR metabolites in the mixture with phenanthrene or fluoranthene.
KW - Bacteria degradation
KW - Fluoranthene
KW - Phenanthrene
KW - Polycyclic aromatic hydrocarbon
KW - Solid-phase microextraction
UR - http://www.scopus.com/inward/record.url?scp=33846121587&partnerID=8YFLogxK
U2 - 10.1897/06-042R.1
DO - 10.1897/06-042R.1
M3 - Article
C2 - 17089707
AN - SCOPUS:33846121587
SN - 0730-7268
VL - 25
SP - 2853
EP - 2859
JO - Environmental Toxicology and Chemistry
JF - Environmental Toxicology and Chemistry
IS - 11
ER -