Blosser R S, Gray K M
Department of Biology, University of South Florida, Tampa 33620, USA.
J Microbiol Methods. 2000 Mar;40(1):47-55. doi: 10.1016/s0167-7012(99)00136-0.
Fatty acyl homoserine lactones (AHLs) are used as extracellular quorum sensing signals by a variety of gram-negative bacteria. By activating proteins belonging to the LuxR family of transcriptional regulators, these signal metabolites allow population density-dependent gene regulation within a species, as well as interspecies communication among different bacteria. The experimental detection of AHLs is important in the identification of quorum sensing capabilities in bacteria. Chromobacterium violaceum is a gram-negative bacterium that produces the purple pigment violacein in response to the presence of the AHL N-hexanoyl homoserine lactone (C6HSL). The mini-Tn5 mutant strain C. violaceum CV0blu is deficient in the production of this signal molecule but retains the ability to synthesize violacein in response to the presence of C6HSL and a variety of other short-chain AHLs. We have developed a quantitative bioassay that measures the amount of violacein produced by this strain in response to the presence of different concentrations of various AHL molecules. This new assay provides a means of quantifying the amount of a given AHL present in a bacterial culture and can be used to measure differences in AHL production among different strains or different batch cultures of a given species.
脂肪酰基高丝氨酸内酯（AHLs）被多种革兰氏阴性菌用作细胞外群体感应信号。通过激活属于LuxR转录调节因子家族的蛋白质，这些信号代谢物允许在一个物种内进行群体密度依赖性基因调控，以及不同细菌之间的种间通讯。AHLs的实验检测对于鉴定细菌中的群体感应能力很重要。紫色杆菌是一种革兰氏阴性菌，它在AHL N-己酰基高丝氨酸内酯（C6HSL）存在时会产生紫色色素紫菌素。迷你Tn5突变株紫色杆菌CV0blu缺乏这种信号分子的产生，但保留了在C6HSL和多种其他短链AHLs存在时合成紫菌素的能力。我们开发了一种定量生物测定法，用于测量该菌株在不同浓度的各种AHL分子存在时产生的紫菌素量。这种新的测定法提供了一种量化细菌培养物中给定AHL量的方法，可用于测量不同菌株或给定物种的不同批次培养物之间AHL产生的差异。
