Desaint S, Arrault S, Siblot S, Fournier J-C
Laboratoire de Microbiologie des Sols, Centre de Microbiologie du Sol et de l'Environnement, INRA, Dijon Cedex, France.
J Appl Microbiol. 2003;95(1):102-8. doi: 10.1046/j.1365-2672.2003.01965.x.
To investigate the role of horizontal gene transfer of mcd (methylcarbamate-degrading) gene in high genetic diversity of carbofuran-degrading bacteria.
The actuality of genetic transfer from degraders to an Agrobacterium tumefaciens strain was determined in liquid medium. The mcd gene was chosen for transfer experiments. Transconjugants were obtained irrespective of the type of the donor strain (Gram-positive or Gram-negative), size of the inoculum, or nature and concentration of the pesticide in the medium. Soil microcosms, inoculated with or without the donor and/or recipient strains were used. The size of the initial degrading population (treated or untreated soil) and the nature of the inoculated donor strains were considered. More transconjugants were isolated in the previously treated soil than in the untreated soil. Agrobacterium transconjugants were isolated even when the donor strain was not inoculated, probably as a result of gene transfer from indigenous degrading population to the recipient strain. Moreover, potential transconjugants belonging to the Pseudomonas genus were isolated.
Our results seem to demonstrate that the mcd gene is transferable in soil among bacterial populations.
The transfer of the mcd gene is partly responsible for the high genetic diversity of micro-organisms able to catabolize carbofuran.
研究甲萘威降解基因（mcd）水平基因转移在克百威降解菌高遗传多样性中的作用。
在液体培养基中测定从降解菌到根癌土壤杆菌菌株的基因转移现状。选择mcd基因进行转移实验。无论供体菌株类型（革兰氏阳性或革兰氏阴性）、接种物大小或培养基中农药的性质和浓度如何，均可获得接合子。使用接种或未接种供体和/或受体菌株的土壤微观世界。考虑初始降解菌群（处理过或未处理过的土壤）的大小和接种的供体菌株的性质。与未处理过的土壤相比，在先前处理过的土壤中分离出更多的接合子。即使未接种供体菌株，也能分离出根癌土壤杆菌接合子，这可能是由于基因从本地降解菌群转移到受体菌株的结果。此外，还分离出了属于假单胞菌属的潜在接合子。
我们的结果似乎表明，mcd基因可在土壤中的细菌群体之间转移。
mcd基因的转移部分导致了能够分解克百威的微生物的高遗传多样性。
