Microbial Phosphotriesterase: Structure, Function, and Biotechnological Applications

Abstract

The role of phosphotriesterase as an enzyme which is able to hydrolyze organophosphate compounds cannot be disputed. Contamination by organophosphate (OP) compounds in the environment is alarming, and even more worrying is the toxicity of this compound, which affects the nervous system. Thus, it is important to find a safer way to detoxify, detect and recuperate from the toxicity effects of this compound. Phosphotriesterases (PTEs) are mostly isolated from soil bacteria and are classified as metalloenzymes or metal-dependent enzymes that contain bimetals at the active site. There are three separate pockets to accommodate the substrate into the active site of each PTE. This enzyme generally shows a high catalytic activity towards phosphotriesters. These microbial enzymes are robust and easy to manipulate. Currently, PTEs are widely studied for the detection, detoxification, and enzyme therapies for OP compound poisoning incidents. The discovery and understanding of PTEs would pave ways for greener approaches in biotechnological applications and to solve environmental issues relating to OP contamination.

Green MIP-202(Zr) Catalyst: Degradation and Thermally Robust Biomimetic Sensing of Nerve Agents

“…Realizing rapid and reliable degradation and detection of highly toxic nerve agent (NA) threats has become increasingly crucial for homeland security and health protection of warfighters and civilians. Conventional bacterial enzymes with phosphotriesterase-like activity (phosphotriesterases, PTEs) represent the gold standard for efficient biocatalytic degradation of NAs. − Such enzymes are also widely used for on-site detection of NAs in connection to different electrochemical or optical transducers. − However, their potential for demanding on-site security and defense applications is seriously hindered by their limited thermal and storage stabilities, pH resiliency, and chemical resistance. − An attractive strategy for improving the NA degradation performance of these enzymes has involved encapsulation within metal–organic framework (MOF) structures that leads to enhanced catalytic turnover rate, conversion efficiency, thermal stability, and/or cascade conversion capability. ,, However, these enzymes still suffer from some instability upon extended storage at elevated temperatures …”

Rapid, Biomimetic Degradation of a Nerve Agent Simulant by Incorporating Imidazole Bases into a Metal–Organic Framework

“…27 Specifically, these ligated groups serve as proximate bases in the catalytic cycle, promoting proton transfer and the regeneration of the active binuclear Zn centers of PTE. 17,28,29 In essence, the binuclear Zn center and the surrounding ligands work collaboratively, enabling the extraordinary catalytic activities of PTE. The high cost and poor stability of PTE, however, has limited its practical application in nerve agent detoxification.…”

Immobilization of Mutant Phosphotriesterase on Fuller’s Earth Enhanced the Stability of the Enzyme

“…Phospotriesterase (PTE) is an enzyme that is known to be able to hydrolyze toxic organophosphate esters (OP) into non-toxic compounds [3,4]. This toxic functionality is widely present in various industries such as in agriculture, petroleum, plasticizer production, textile manufacturing and they have also been used as chemical warfare agents [5,6]. Thus, the utilization of PTE as a means to inactivate OPs is an application that could address concerns about their use and subsequent inactivation after use in these industries.…”