了解細菌與動物之間的互利關(guān)系,，對于包括病原微生物學(xué)在內(nèi)的生物學(xué)的幾個領(lǐng)域來說越來越重要。很多病原體對某一種宿主或組織具有特異性,，但這種特異性的分子基礎(chǔ)基本上還不清楚,。
現(xiàn)在，對名為Euprymna scolopes的烏賊與生物發(fā)光細菌Vibrio fischeri之間的互利關(guān)系中的宿主特異性所做的一項比較基因組研究表明,，一個細菌基因（即調(diào)控基因rscS）的存在可改變宿主范圍,。當(dāng)這個基因在該細菌通常在日本松毬魚身上寄生的菌種中表達時，它足以形成一個共生生物膜,，這個膜是細菌在烏賊身上生存的關(guān)鍵,。
這項工作提出一個可能性：為了治療之目的,，也許可對人病原體的特異性進行類似操縱。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature 458, 215-218 (12 March 2009) | doi:10.1038/nature07660
A single regulatory gene is sufficient to alter bacterial host range
Mark J. Mandel1, Michael S. Wollenberg1, Eric V. Stabb2, Karen L. Visick3 & Edward G. Ruby1
1 Department of Medical Microbiology and Immunology, University of Wisconsin School of Medicine and Public Health, 1550 Linden Drive, Madison, Wisconsin 53706, USA
2 Department of Microbiology, University of Georgia, 828 Biological Sciences, Athens, Georgia 30602, USA
3 Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois 60153, USA
Correspondence to: Mark J. Mandel1 Correspondence and requests for materials should be addressed to M.J.M.
Microbial symbioses are essential for the normal development and growth of animals1, 2, 3. Often, symbionts must be acquired from the environment during each generation, and identification of the relevant symbiotic partner against a myriad of unwanted relationships is a formidable task4. Although examples of this specificity are well-documented, the genetic mechanisms governing it are poorly characterized5. Here we show that the two-component sensor kinase RscS is necessary and sufficient for conferring efficient colonization of Euprymna scolopes squid by bioluminescent Vibrio fischeri from the North Pacific Ocean. In the squid symbiont V. fischeri ES114, RscS controls light-organ colonization by inducing the Syp exopolysaccharide, a mediator of biofilm formation during initial infection. A genome-level comparison revealed that rscS, although present in squid symbionts, is absent from the fish symbiont V. fischeri MJ11. We found that heterologous expression of RscS in strain MJ11 conferred the ability to colonize E. scolopes in a manner comparable to that of natural squid isolates. Furthermore, phylogenetic analyses support an important role for rscS in the evolution of the squid symbiosis. Our results demonstrate that a regulatory gene can alter the host range of animal-associated bacteria. We show that, by encoding a regulator and not an effector that interacts directly with the host, a single gene can contribute to the evolution of host specificity by switching 'on' pre-existing capabilities for interaction with animal tissue.
