Dandie C E, Thomas S M, Bentham R H, McClure N C
School of Biological Sciences, Flinders University of South Australia, Adelaide, Australia.
J Appl Microbiol. 2004;97(2):246-55. doi: 10.1111/j.1365-2672.2004.02087.x.
The aim of this study was to further characterize a bacterial culture (VUN 10,010) capable of benzo[a]pyrene cometabolism.
The bacterial culture, previously characterized as a pure culture of Stenotrophomonas maltophilia (VUN 10,010), was found to also contain another bacterial species (Mycobacterium sp. strain 1B), capable of degrading a similar range of PAH substrates. Analysis of its 16S rRNA gene sequence and growth characteristics revealed the strain to be a fast-growing Mycobacterium sp., closely related to other previously isolated PAH and xenobiotic-degrading mycobacterial strains. Comparison of the PAH-degrading characteristics of Mycobacterium sp. strain 1B with those of S. maltophilia indicated some similarities (ability to degrade phenanthrene and pyrene), but some differences were also noted (S. maltophilia able to degrade fluorene, but not fluoranthene, whereas Mycobacterium sp. strain 1B can degrade fluoranthene, but not fluorene). Unlike the S. maltophilia culture, there was no evidence of benzo[a]pyrene degradation by Mycobacterium sp. strain 1B, even in the presence of other PAHs (ie pyrene) as co-metabolic substrates. Growth of Mycobacterium sp. strain 1B on other organic carbon sources was also limited compared with the S. maltophilia culture.
This study isolated a Mycobacterium strain from a bacterial culture capable of benzo[a]pyrene cometabolism. The Mycobacterium strain displays different PAH-degrading characteristics to those described previously for the PAH-degrading bacterial culture. It is unclear what role the two bacterial strains play in benzo[a]pyrene cometabolism, as the Mycobacterium strain does not appear to have endogenous benzo[a]pyrene degrading ability.
This study describes the isolation and characterization of a novel PAH-degrading Mycobacterium strain from a PAH-degrading culture. Further studies utilizing this strain alone, and in combination with other members of the consortium, will provide insight into the diverse roles different bacteria may play in PAH degradation in mixed cultures and in the environment.
本研究的目的是进一步鉴定一种能够进行苯并[a]芘共代谢的细菌培养物（VUN 10,010）。
该细菌培养物先前被鉴定为嗜麦芽窄食单胞菌的纯培养物（VUN 10,010），现发现其还含有另一种细菌（分枝杆菌属菌株1B），该菌株能够降解一系列类似的多环芳烃底物。对其16S rRNA基因序列和生长特性的分析表明，该菌株是一种快速生长的分枝杆菌属，与其他先前分离的多环芳烃和异生素降解分枝杆菌菌株密切相关。将分枝杆菌属菌株1B与嗜麦芽窄食单胞菌的多环芳烃降解特性进行比较，发现了一些相似之处（都有降解菲和芘的能力），但也存在一些差异（嗜麦芽窄食单胞菌能够降解芴，但不能降解荧蒽，而分枝杆菌属菌株1B能够降解荧蒽，但不能降解芴）。与嗜麦芽窄食单胞菌培养物不同，即使存在其他多环芳烃（如芘）作为共代谢底物，也没有证据表明分枝杆菌属菌株1B能够降解苯并[a]芘。与嗜麦芽窄食单胞菌培养物相比，分枝杆菌属菌株1B在其他有机碳源上的生长也受到限制。
本研究从一种能够进行苯并[a]芘共代谢的细菌培养物中分离出了一种分枝杆菌菌株。该分枝杆菌菌株显示出与先前描述的多环芳烃降解细菌培养物不同的多环芳烃降解特性。目前尚不清楚这两种细菌菌株在苯并[a]芘共代谢中发挥何种作用，因为该分枝杆菌菌株似乎没有内源性苯并[a]芘降解能力。
本研究描述了从一种多环芳烃降解培养物中分离和鉴定出一种新型多环芳烃降解分枝杆菌菌株。进一步单独利用该菌株以及与该联合体的其他成员联合进行研究，将有助于深入了解不同细菌在混合培养物和环境中的多环芳烃降解中可能发挥的不同作用。
