Department of Chemical Engineering, Texas A & M University, College Station, TX, USA.
ISME J. 2012 Jul;6(7):1356-66. doi: 10.1038/ismej.2011.210. Epub 2012 Jan 12.
Flies transport specific bacteria with their larvae that provide a wider range of nutrients for those bacteria. Our hypothesis was that this symbiotic interaction may depend on interkingdom signaling. We obtained Proteus mirabilis from the salivary glands of the blow fly Lucilia sericata; this strain swarmed significantly and produced a strong odor that attracts blow flies. To identify the putative interkingdom signals for the bacterium and flies, we reasoned that as swarming is used by this bacterium to cover the food resource and requires bacterial signaling, the same bacterial signals used for swarming may be used to communicate with blow flies. Using transposon mutagenesis, we identified six novel genes for swarming (ureR, fis, hybG, zapB, fadE and PROSTU_03490), then, confirming our hypothesis, we discovered that fly attractants, lactic acid, phenol, NaOH, KOH and ammonia, restore swarming for cells with the swarming mutations. Hence, compounds produced by the bacterium that attract flies also are utilized for swarming. In addition, bacteria with the swarming mutation rfaL attracted fewer blow flies and reduced the number of eggs laid by the flies. Therefore, we have identified several interkingdom signals between P. mirabilis and blow flies.
蝇类幼虫携带特定的细菌，为这些细菌提供更广泛的营养。我们的假设是，这种共生相互作用可能依赖于跨物种信号。我们从丝光绿蝇的唾液腺中获得了奇异变形杆菌；该菌株显著聚集，并产生强烈的气味吸引苍蝇。为了确定细菌和苍蝇之间的假定跨物种信号，我们推断，由于这种细菌用聚集来覆盖食物资源，并且需要细菌信号，因此用于聚集的相同细菌信号可能用于与苍蝇进行通信。使用转座子诱变，我们鉴定了六个用于聚集的新基因（ureR、fis、hybG、zapB、fadE 和 PROSTU_03490），然后，证实了我们的假设，我们发现苍蝇引诱剂，乳酸、苯酚、NaOH、KOH 和氨，恢复了具有聚集突变的细胞的聚集。因此，吸引苍蝇的细菌产生的化合物也被用于聚集。此外，具有聚集突变 rfaL 的细菌吸引的苍蝇更少，并且减少了苍蝇产卵的数量。因此，我们已经确定了奇异变形杆菌和苍蝇之间的几种跨物种信号。
