含酚废水处理系统中苯酚降解菌的分离及分离物多样性分析

Isolation and diversity analysis of phenol-degrading bacteria in a wastewater treatment plant

用富集培养和直接涂平板培养的方法,从含酚废水处理系统的悬浮污泥中分别分离了57株和55株苯酚降解菌.112株分离物经ERIC-PCR指纹图谱分析,共显示了15种差异明显的ERIC-PCR指纹图谱,表明至少应有15种不同的菌株,其中直接涂平板法得到的分离物占有11种,富集培养法得到的分离物占4种.将直接涂平板得到的分离物,与来自不同种属苯酚降解菌的LmPH（the largest subunit of multi-componentphenol hydroxylase）等位基因分子进行杂交显示,该11种分离物可分为3种以上不同的LmPH代谢类型;而富集培养获得的分离物中只显示1种LmPH代谢类型.对显示不同ERIC-PCR指纹图的15个代表菌株的生长和苯酚降解效率进行研究发现,其中F-6菌株在苯酚浓度0.4-1.4g·L^-1范围内,其苯酚降解效率达到了70%-100%.

Phenol-degrading bacteria were isolated and purified from wastewater treatment sludge samples. Using direct plating methods, 55 isolates were obtained, and by enrichment culture methods, 57 isolates were identified. Fifteen dramatically different patterns were found in the 112 isolates through analysis of the ERIC-PCR （enterobacterial repetitive intergenic consensus sequence PCR） genomic fingerprints and thus at least 15 different strains were present. Among these 15 different strains, 11 strains were obtained through the direct plating and 4 strains obtained through the enrichment culture. Southern blot was carried out to compare the metabolic types among the 15 different strains with probes, whieh were labeled from the LmPH （the largest subunit of multi-component phenol hydroxylase） allelic genes of Pseudomonas putida H and Acinetobacter calcoaceticus NCIB8250. The result showed that the 11 strains from the direct plating could be divided into at least 3 LmPH metabolic types, while the 4 strains from the enrichment culture contained only 1 LmPH metabolic type. The phenol degradation rate of the 15 representative strains which had different ERIC-PCR genomic fingerprints was analyzed. Strain F-6 had a phenol degradation rate of 70% - 100% over a phenol concentration range of 0.4 - 1.4 g· L^-1.