A Novel Glutathione -Transferase Gtt2 Class (VpGSTT2) Is Found in the Genome of the AHPND/EMS Shrimp Pathogen.

Glutathione S-transferases are a family of detoxifying enzymes that catalyze the conjugation of reduced glutathione (GSH) with different xenobiotic compounds using either Ser, Tyr, or Cys as a primary catalytic residue. We identified a novel GST in the genome of the shrimp pathogen FIM- S1708, a bacterial strain associated with Acute Hepatopancreatic Necrosis Disease (AHPND)/Early Mortality Syndrome (EMS) in cultured shrimp. This new GST class was named Gtt2.

Comparative Studies of Structures and Peroxidase-like Activities of Copper(II) and Iron(III) Complexes with an EDTA-Based Phenylene-Macrocycle and Its Acyclic Analogue.

With the objective of studying the conformational and macrocyclic effects of selected metal chelates on their peroxidase activities, Cu and Fe complexes were synthesized with a macrocyclic derivative of ethylenediaminetetraacetic acid and -phenylenediamine (abbreviated as edtaodH) and its new open-chain analogue (edtabzH). The Fe complex of edtaodH has a peroxidase-like activity, whereas the complex of edtabzH does not. The X-ray study of the former shows the formation of a dimeric molecule {[Fe(edtaod)]O} in which each metal with an octahedral coordination is overposed over the macrocyclic cavity, as a result of rigid macrocyclic frame, to form an Fe-O-Fe bridge; the exposure of the central metal to the environment facilitates the capture of oxygen to drive the biomimetic activity.

Syntheses, Characterization, and Antioxidant Evaluation of Cu, Mn, and Fe Complexes with a 14 Membered EDTA-Derived Macrocycle.

The Cu, Mn, and Fe complexes of a 14 membered macrocycle were synthesized and their antioxidant capacities were evaluated against ABTS and DPPH radicals, with the objective of collecting insights into the biomimetic role of the central metal ions. The macrocycle, abbreviated as HL14, is a derivative of EDTA cyclized with 1,4-diamine, and the moderately flexible macrocyclic frame permits the formation of [ML14·HO] chelates with octahedral coordination geometries common among the metal ions. The metal complexes were characterized by electrospray-ionization mass spectrometry, Fourier transform infrared spectroscopy, and Raman and X-ray photoelectron spectroscopic methods, as well as thermogravimetric analysis; the octahedral coordination geometries with water coordination were optimized by DFT calculations.