Structural basis of transcription factor YhaJ for DNT detection

Myeongbin Kim; Ryun Kang; Tae Jin Jeon; Seong Eon Ryu

doi:10.1016/j.isci.2023.107984

Structural basis of transcription factor YhaJ for DNT detection

iScience. 2023 Sep 21;26(10):107984. doi: 10.1016/j.isci.2023.107984. eCollection 2023 Oct 20.

Authors

Myeongbin Kim¹, Ryun Kang¹, Tae Jin Jeon^{1

2}, Seong Eon Ryu¹

Affiliations

¹ Department of Bioengineering, College of Engineering, Hanyang University, Seoul 04673, Republic of Korea.
² National Instrumentation Center for Environmental Management (NICEM), Seoul National University, Seoul 08826, Republic of Korea.

Abstract

Detection of landmines without harming personnel is a global issue. The bacterial transcription factor YhaJ selectively detects metabolites of explosives, and it can be used as a key component of DNT biosensors. However, the wild-type YhaJ has a binding affinity that is not sufficient for the detection of trace amounts of explosives leaked from landmines buried in the soil. Here, we report crystal structures of the effector-binding domain of YhaJ in both the apo- and effector-bound forms. A structural comparison of the two forms revealed that the loop above the primary effector-binding site significantly switches its conformation upon effector binding. The primary effector-binding site involves hydrophobic and polar interactions, having specificity to hydroxyl-substituted benzene compounds. The structures explain the mechanism of activity-enhancing mutations and provide information for the rational engineering of YhaJ biosensors for the sensitive detection of explosives.

Keywords: Biomaterials; Materials property; Materials science.