Mahiudddin Md, Fakhruddin A N M
Department of Environmental Sciences, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh.
ISRN Microbiol. 2012 Jan 23;2012:741820. doi: 10.5402/2012/741820. Print 2012.
Degradation of phenolics by members of soil microflora is an important means by which these substances are removed from the environment thus reducing environmental pollution. Biodegradation by microorganisms offers unique opportunities to destroy or render phenolic compounds. A bacterium, PU1, identified as Pseudomonas fluorescens PU1, was investigated for its ability to grow on and degrade phenols as sole carbon sources in aerobic shaking batch culture. The organism degraded up to 1000 ppm of phenol using meta cleavage pathway. The pathways for phenol degradation were proposed by the identification of metabolites and assay of ring cleavage enzymes in cell extracts. Phenol was degraded via catechol with subsequent metaring cleavage. Cell growth increased as the phenol concentrations increased up to 1000 ppm phenol. The biodegradation efficiency, degradation extent, and metabolic pathway of phenol were determined to provide useful clues for further application of this isolate in the engineered bioremediation systems. The paper's results suggest that Pseudomonas fluorescens PU1 strain could be a good candidate for remediation of phenol contaminants from heavily polluted sites.
土壤微生物群落成员对酚类物质的降解是这些物质从环境中去除从而减少环境污染的重要途径。微生物的生物降解为破坏或转化酚类化合物提供了独特的机会。一种被鉴定为荧光假单胞菌PU1的细菌,在好氧振荡分批培养中,研究了其以酚类作为唯一碳源生长和降解的能力。该微生物利用间位裂解途径降解高达1000 ppm的苯酚。通过鉴定代谢产物和测定细胞提取物中环裂解酶来推测苯酚的降解途径。苯酚通过儿茶酚降解,随后进行间环裂解。随着苯酚浓度增加至1000 ppm,细胞生长增加。测定了苯酚的生物降解效率、降解程度和代谢途径,为该分离物在工程生物修复系统中的进一步应用提供有用线索。该论文的结果表明,荧光假单胞菌PU1菌株可能是从重度污染场地修复苯酚污染物的良好候选菌株。