Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, 76019, USA.
AZYP LLC, 700 Planetarium Place, Arlington, TX, 76019, USA.
Anal Bioanal Chem. 2020 May;412(12):2927-2937. doi: 10.1007/s00216-020-02534-7. Epub 2020 Mar 20.
Homoserine lactones (HSLs) are signaling molecules synthesized by Gram-negative bacteria in order to communicate in a process termed "quorum sensing." Until recently, only the L-stereoisomers of HSLs were thought to be produced and able to incite quorum sensing. However, recent studies have shown that select Gram-negative bacteria additionally produce non-trivial amounts of D-HSLs which may also play a role in quorum sensing. Current methods for the separation of HSL enantiomers cannot effectively separate all classes of HSLs and its enantiomers. More robust methods of separation and detection of D-HSLs are necessary. We have developed rapid and selective methods using liquid chromatography (LC) and gas chromatography (GC) coupled with mass spectrometry (MS) which can simultaneously enantiomerically separate all classes of HSLs. The advantages of these methods are in the MS compatibility as well as the ability to enantiomerically separate all classes of HSLs in a single run. The first enantiomeric separations of oxo- and hydroxy-HSLs by GC-MS, through the use of N,O-bis(trimethylsilyl)trifluoroacetamide-derivatizing reagents are discussed. Graphical Abstract.
同型高丝氨酸内酯（HSLs）是革兰氏阴性细菌合成的信号分子，用于进行称为“群体感应”的过程中的通信。直到最近，人们认为只有 HSL 的 L-对映异构体被产生并且能够引发群体感应。然而，最近的研究表明，一些革兰氏阴性细菌还会产生大量非手性的 D-HSL，其也可能在群体感应中发挥作用。目前用于分离 HSL 对映异构体的方法不能有效地分离所有类别的 HSL 及其对映异构体。需要更强大的 D-HSL 分离和检测方法。我们已经开发了使用液相色谱（LC）和气相色谱（GC）与质谱（MS）联用的快速和选择性方法，这些方法可以同时对映异构体分离所有类别的 HSL。这些方法的优点在于与 MS 的兼容性以及在单次运行中对映异构体分离所有类别的 HSL 的能力。通过使用 N，O-双（三甲基硅基）三氟乙酰胺衍生化试剂，首次通过 GC-MS 对氧代和羟基 HSL 进行对映异构体分离。
