Publications by authors named "Marco Melzer"
Article Synopsis
- - Highly toxic organophosphorus compounds, like nerve agents (sarin, tabun), irreversibly inhibit the enzyme acetylcholinesterase (AChE), posing serious risks to both civilians and military personnel, leading to research for new antidotes.
- - One promising candidate is diisopropyl fluorophosphatase (DFPase) from squid, which can detoxify these nerve agents; scientists are modifying it with polyethylene glycol (PEG) to improve its effectiveness and reduce immune reactions.
- - Testing in rats shows that a mutant form of PEGylated DFPase not only prevents death from high doses of soman but also reduces poisoning symptoms, indicating that engineered variants could be effective treatments if
Article Synopsis
- Buffer compounds like TRIS are essential for controlling pH in various chemical and biomedical applications, but they can react with substances in the solution, which is critical in analytical chemistry.
- Research on the enzymatic breakdown of G-type nerve agents (sarin, soman, and cyclosarin) found that TRIS and other buffer compounds form stable adducts with these agents.
- It's suggested to use alternative buffers such as MOPS, MES, and CHES instead of TRIS at higher concentrations and for longer durations to avoid unwanted reactions.
The enzyme diisopropyl fluorophosphatase (DFPase, EC 3.1.8.
View Article and Find Full Text PDFDiisopropyl fluorophosphatase (DFPase) from Loligo vulgaris is an efficient and robust biocatalyst for the hydrolysis of a range of highly toxic organophosphorus compounds including the nerve agents sarin, soman, and cyclosarin. In contrast to the substrate diisopropyl fluorophosphate (DFP) the nerve agents possess an asymmetric phosphorus atom, which leads to pairs of enantiomers that display markedly different toxicities. Wild-type DFPase prefers the less toxic stereoisomers of the substrates which leads to slower detoxification despite rapid hydrolysis.
View Article and Find Full Text PDFThe enzyme diisopropyl fluorophosphatase (DFPase) from the squid Loligo vulgaris effectively catalyzes the hydrolysis of diisopropyl fluorophosphate (DFP) and a number of organophosphorus nerve agents, including sarin, soman, cyclosarin, and tabun. Up to now, the determination of kinetic data has been achieved by techniques such as pH-stat titration, ion-selective electrodes, and fluorogenic substrate analogs. We report a new assaying method using in situ Fourier transform infrared (FTIR) spectroscopy with attenuated total reflection (ATR) for the real-time determination of reaction rates.
View Article and Find Full Text PDFTreatment regimen of poisonings by organophosphorus (OP) compounds usually includes oxime therapy. The treatment options in soman poisoning are very limited due to rapid aging of the inhibited acetylcholinesterase (AChE), when the enzyme species is considered as irreversibly inhibited and resistant towards reactivation by oximes. Hence, oxime treatment probably comes too late in realistic scenarios.
View Article and Find Full Text PDF