Preliminary study on the correlation between enzyme activity assays and substrate preferences of microbial transglutaminase

Abstract Transglutaminase (TGase) derived from microorganisms, known for its exceptional protein cross-linking properties, holds significant application potential across various fields. In order to meet market demands such as temperature preferences, catalytic capabilities, selectivity, and the exploration of novel TGases, challenges have arisen for the development of TGases. In this study, we conducted enzymatic activity assays on TGases from Shouchella clausii (strain KSM-K16) (Alkalihalobacillus clausii) and Couchioplanes caeruleus, randomly selected from the TrEMBL database in UniProt. We also simulated the reaction process of these assays and provided interpretations of the results. Subsequently, we examined their cross-linking abilities with protein substrates bovine serum albumin (BSA) and soy protein isolate. By validating with commercial TGase, we identified the correlation between the two commonly used enzymatic activity assay methods for TGase and the substrate preference of TGase. This correlation will aid in the specific modification of TGase.