Characteristics and Kinetic Study of 2-Hydroxypyridine Degradation by a Novel Bacterium Arthrobacter sp.2PR / 中国生物工程杂志

ABSTRACT

A novel strain,which could use 2-hydroxypyridine (2HP) as the sole source of carbon,nitrogen,and energy,was isolated from petroleum-contaminated soil at the Liaohe estuarine wetland.Strain 2PR was identified as Arthrobacter based on the morphology and 16S rRNA gene sequence.The optimum growth and degradation condition upon 2PR is 30℃ and pH 7.0,respectively.Under this condition,2HP degradation rate were 97.34％,94.95％,94.48％ and 89.21％ with 2,4,6 and 8 mg/ml initial concentration of 2HP at 42,96,120 and 156 h,respectively.Strain growth and 2HP degradation kinetics studies indicated that the strain followed Logisitic model,which could provide a theoretical and technical reference for the biodegradation of 2HP.The color of strain 2PR culture upon 2HP-MSN changed from colorless to blue,and then turned to brown.The blue pigment,which was observed at the culture of strain 2PR,was identified as 4,5,4',5'-tetrahydroxy-3,3'-diazadiphenoquinone-(2,2') by high performance liquid chromatography (HPLC) and high-performance liquid chromatography-mass spectrometry (LC-MS) analysis.The LC-MS signal with m/z =249.1 was observed in resting cells reaction sample with 2HP as the substrate.The degradation of 2HP might be achieved by a dioxygenase to produce 2,3,6-trihydroxypyridine,which could transformed to the blue pigment spontaneously,and then 2,3,6-trihydroxypyridine was converted with an pyridine-ring cleavage reaction.Among all the reported strains,strain 2PR has the strongest tolerance and the highest 2HP degradation efficiency at present.The strain has a promising application potential for 2HP waste treatment.