[Degradation of p-nitrophenol by a mangrove bacterial Rhodococcus sp. Ns].
A bacterium capable of utilizing p-nitrophenol (PNP) as the sole nitrogen, carbon, and energy source was isolated from mangrove sediment. This bacterium was confirmed based on 16S rDNA sequence analysis and taxonomic analysis as being a member of the genus Rhodococcus and was designated strain Ns. The strain Ns could tolerate high concentrations of PNP up to 1.5 mmol/L and complete degradation was achieved in four days at 30 degrees C in the dark under aerobic conditions. Biodegradation of PNP quickly occurred at optimal pH above 5.0, and at least 5 per thousand salinity. Bacterial growth on PNP was observed with the simultaneous production of 4-nitrocatechol, which was also degraded by the same bacterium, as a degradation intermediate, Moreover, Rhodococcus sp. Ns was able to also deplete 2-nitrophenol(ONP) as the sole source of carbon, nitrogen and energy, but not 3-nitrophenol. The experimental results show that bacteria indigenous to the natural wetland sediment are capable of complete degradation of PNP and ONP.
Wan
Nian-Sheng
NS
LED, South China Sea Institute of Oceanography , Chinese Academy of Sciences, Guangzhou 510301, Chinar. nianshengwan@yahoo.com.cn
Gu
Ji-Dong
JD
Hao
Fu-Qin
FQ
Xiao
Xiang-Qun
XQ
D001673:Biodegradation, Environmental; D009596:Nitrophenols / Q000378:metabolism*; D043982:Rhizophoraceae / Q000382:microbiology*; D012240:Rhodococcus / Q000378:metabolism*
D009596:Nitrophenols; C024836:4-nitrophenol