Gülensoy N, Alvarez P J
University of Iowa, Department of Civil and Environmental Engineering, Iowa City 52242-1527, USA.
Biodegradation. 1999;10(5):331-40. doi: 10.1023/a:1008318405882.
This work investigated the biodegradation capabilities of indigenous microorganisms exposed to different combinations of aromatic hydrocarbons. Considerable diversity was found in the catabolic specificity of 55 strains. Toluene was the most commonly degraded compound, followed by p-xylene, m-xylene and ethylbenzene. Strains capable of degrading o-xylene and benzene, which were the least-frequently-degraded compounds, exhibited broader biodegradation capabilities. Kappa statistics showed a significant correlation between the abilities to degrade toluene and ethylbenzene, p-xylene and m-xylene, and p-xylene and o-xylene. The ability to degrade naphthalene was correlated to the ability to degrade other alkylbenzenes, but not benzene. In addition, the inability to degrade benzene was correlated to the inability to degrade o-xylene. Factorial analysis of variance showed that biodegradation capabilities were generally broader when aromatic hydrocarbons were fed as mixtures than when fed separately. Beneficial substrate interactions included enhanced degradation of benzene, p-xylene, and naphthalene when toluene was present, and enhanced degradation of naphthalene by ethylbenzene. Such heuristic relationships may be useful to predict biodegradation patterns when bacteria are exposed to different aromatic hydrocarbon mixtures.
这项研究调查了暴露于不同芳烃组合的本地微生物的生物降解能力。发现55株菌株的分解代谢特异性存在相当大的差异。甲苯是最常被降解的化合物，其次是对二甲苯、间二甲苯和乙苯。能够降解邻二甲苯和苯（这两种是最不常被降解的化合物）的菌株表现出更广泛的生物降解能力。卡帕统计显示，降解甲苯和乙苯、对二甲苯和间二甲苯以及对二甲苯和邻二甲苯的能力之间存在显著相关性。降解萘的能力与降解其他烷基苯的能力相关，但与降解苯的能力无关。此外，不能降解苯与不能降解邻二甲苯相关。方差析因分析表明，当芳烃以混合物形式投喂时，生物降解能力通常比单独投喂时更广泛。有益的底物相互作用包括当存在甲苯时苯、对二甲苯和萘的降解增强，以及乙苯对萘的降解增强。当细菌暴露于不同的芳烃混合物时，这种启发式关系可能有助于预测生物降解模式。
