Application of fluorescence markers for diagnosis of bacterial assemblage: hydrolytic enzyme activity in aquatic ecosystem

Abstract

Most of existing methods to monitor enzymatic activity in microbial culture cannot be applied directly to study hydrolytic activities in aquatic environments. The low natural substrate concentrations as well as the sub optimal in situ environmental conditions (unsuitable temperature, pH and the presence of interfering substrates) make the existing laboratory methods often inadequate to measure enzymatic activity. Recently, molecular fluorosensors are commonly used for sensitive assays involved in examining hydrolytic activity in aquatic environment in situ. These allow for simpler and more rapid measurement of hydrolytic enzyme activity. Furthermore, the stability of the artificial substrates produces very low fluorescence background and can be used without any loss in sensitivity at high concentration (mM) that are sometimes required to measure enzyme saturation.