Melavanki Raveendra, Kusanur Raviraj, Sadasivuni Kishor Kumar, Singh Diksha, Patil N R
Department of Physics, M S Ramaiah Institute of Technology, Bangalore, Karnataka, 560054, India.
Department of Chemistry, R V College of Engineering, Bangalore, Karnataka, 560059, India.
Heliyon. 2020 Oct 7;6(10):e05081. doi: 10.1016/j.heliyon.2020.e05081. eCollection 2020 Oct.
Binding interactions of boronic acid derivatives viz. 2-Methylphenylboronic acid (B1) and 3-Methoxyphenylboronic acid (B2) with mono saccharides (arabinose, fructose and galactose) and disaccharides (sucrose, lactose and maltose) in aqueous condition at pH 7.4 by means of fluorescence spectroscopy is reported in the present investigation. Sugar sensing as well as continuous glucose monitoring (CGM) plays a significant role in diabetes regulation. Sugar sensors mediated through enzymes have their own drawbacks, which led to encouragement to search for designing new sensors through alternate approaches. Among many, fluorescence-based sensors are drawing more attention. Boronic acid-based fluorescence sensors have the capacity to bind reversibly with diols, which makes their demand high in applications. Addition of sugar reduces fluorescence intensities. Change in intensities is associated to cleavage of intermolecular hydrogen bonding which leads in reduced stability of boronate ester. Lineweaver-Burk and Benesi-Hildebrand equation is used for analysing data. Mono sugars are estimated to have higher binding constants. Mutarotation leads to structural changes in saccharides which play a key role in binding interactions. Sugars in furanose form are found to be highly favoured for binding. Molecular docking of B1 and B2 with proteins with PDB ID: 2IPL and 2IPM being periplasmic was done with the help of Schrodinger Maestro 11.2 version. GLIDE scores terms are used for expressing binding affinity.
本研究报道了在pH 7.4的水溶液条件下，通过荧光光谱法研究硼酸衍生物即2-甲基苯硼酸（B1）和3-甲氧基苯硼酸（B2）与单糖（阿拉伯糖、果糖和半乳糖）及二糖（蔗糖、乳糖和麦芽糖）的结合相互作用。糖传感以及连续血糖监测（CGM）在糖尿病调控中起着重要作用。基于酶的糖传感器有其自身的缺点，这促使人们鼓励通过其他方法寻找设计新型传感器的途径。在众多方法中，基于荧光的传感器越来越受到关注。基于硼酸的荧光传感器能够与二醇可逆结合，这使得它们在应用中的需求很高。添加糖会降低荧光强度。强度变化与分子间氢键的断裂有关，这导致硼酸酯的稳定性降低。使用Lineweaver-Burk和Benesi-Hildebrand方程分析数据。据估计，单糖具有更高的结合常数。变旋会导致糖类结构变化，这在结合相互作用中起关键作用。发现呋喃糖形式的糖更有利于结合。借助Schrodinger Maestro 11.2版本对PDB ID为2IPL和2IPM的周质蛋白与B1和B2进行分子对接。使用GLIDE评分项来表达结合亲和力。
