Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069, PR China.
Bioorg Med Chem Lett. 2013 Mar 15;23(6):1676-9. doi: 10.1016/j.bmcl.2013.01.071. Epub 2013 Jan 26.
In an effort to prepare a fluorogenic substrate to be used in activity assays with metallo-β-lactamases, (6R,7R)-8-oxo-7-(2-oxo-2H-chromene-3-carboxamido)-3-((4-(2-oxo-2H-chromene-3-carboxamido)-phenylthio)methyl)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (CA) was synthesized and characterized. CA exhibited a fluorescence quantum yield (φ) of 0.0059, two fluorescence lifetimes of 3.63×10(-10) and 5.38×10(-9)s, and fluorescence intensity that is concentration-dependent. Steady-state kinetic assays revealed that CA is a substrate for metallo-β-lactamases (MβLs) L1 and CcrA, exhibiting Km and kcat values of 18μM and 5s(-1) and 11μM and 17s(-1), respectively.
为了制备用于金属β-内酰胺酶活性测定的荧光底物，合成并表征了（6R,7R）-8-氧代-7-（2-氧代-2H-色烯-3-羧酰胺基）-3-（（4-（2-氧代-2H-色烯-3-羧酰胺基）-苯硫基）甲基）-5-硫-1-氮杂双环[4.2.0]辛-2-烯-2-羧酸（CA）。CA 的荧光量子产率（φ）为 0.0059，具有 3.63×10(-10)和 5.38×10(-9)s 两个荧光寿命，以及与浓度相关的荧光强度。稳态动力学测定表明，CA 是金属β-内酰胺酶（MβLs）L1 和 CcrA 的底物，其 Km 和 kcat 值分别为 18μM 和 5s(-1)以及 11μM 和 17s(-1)。
