研究了接合性质粒pJP4在2株纯菌E.coliDH5α、Alcaligenes sp.及好氧颗粒污泥混合菌群中的水平转移情况,并以获得pJP4质粒的接合子Alcaligenes sp.::pJP4为强化菌种,考察了接合子细胞强化对好氧颗粒反应器和生物膜反应器中难降解有机物2,4-二氯苯氧乙酸(2,4-D)的去除效应.结果表明,pJP4质粒能在E.coli DH5α、Alcaligenes sp.及好氧颗粒污泥中发生水平转移.在2,4-D为唯一碳源及半连续流运行条件下,向好氧颗粒污泥反应器中投加接合子细胞Alcaligenes sp.::pJP4,使系统对2,4-D的平均降解速率提高了12%-1498%.在混合碳源及序批式运行条件下向生物膜反应器中投加Alcaligenes sp.::pJP4,使启动时间从16d缩短到了5d.通过基因强化获得高效接合子,并以其作为生物强化菌种,可以提高生物反应器对特定污染物的去除能力.
The paper first investigated horizontal transfer of a conjugative plasmid pJP4 to two pure strains of E. coli DH5α and Alcaligenes sp. , and a mixed culture of aerobic granular sludge, respectively. With a pJP4 receiving transconjugant Alcaligenes sp. : : pJP4 as the bioaugmented bacteria, bioaugmentation experiments were conducted in an aerobic granular sludge reactor and a biofilm reactor, respectively, to enhance the removal of a recalcitrant compound 2,4-dichlorophenoxyacetic acid(2,4-D). Results showed that pJP4 successfully transferred to E. coli DH5α, Alcaligenes sp. and the mixed culture of aerobic granules. For the aerobic granular sludge reactor operated in semi-continuous mode and fed with 2,4-D sole carbon source wastewater, bioaugmentation with Alcaligenes sp. ::pJP4 increased 2,4-D average removal rate significantly with an enhancement of 12%- 1 498%. For the biofilm reactor operated in sequence batch mode and fed with mixed carbon sources wastewater, supplementation of the transconjugant reduced system start-up time greatly from 16 d to 5 d. It is a feasible strategy to obtain special degradative transconjugants through gene augmentation and put them into bioreactor as bioaugmentation agent to enhance the removal of some specific pollutants.