The formation of cysteine-sulfinic acid has recently become appreciated as a modification that links protein function to cellular oxidative status. Human DJ-1, a protein associated with inherited parkinsonism, readily forms cysteine-sulfinic acid at a conserved cysteine residue (Cys106 in human DJ-1). Mutation of Cys106 causes the protein to lose its normal protective function in cell culture and model organisms.
View Article and Find Full Text PDFThiol redox state (TRS) is an important parameter to reflect intracellular oxidative stress and is associated with various normal and abnormal biochemical processes. Agents that can be used to increase intracellular TRS will be valuable tools in TRS-related research. Glutathione reductase (GR) is a critical enzyme in the homeostasis of TRS.
View Article and Find Full Text PDFDesulfitobacterium dehalogenans can use chlorinated aromatics including polychlorinated biphenyls as electron acceptors in a process called dehalorespiration. Expression of the cpr gene cluster involved in this process is regulated by CprK, which is a member of the CRP/FNR (cAMP-binding protein/fumarate nitrate reduction regulatory protein) family of helix-turn-helix transcriptional regulators. High affinity interaction of the chlorinated aromatic compound with the effector domain of CprK triggers binding of CprK to an upstream target DNA sequence, which leads to transcriptional activation of the cpr gene cluster.
View Article and Find Full Text PDFUnfolding and refolding of rabbit muscle triosephosphate isomerase (TIM), a model for (betaalpha)8-barrel proteins, has been studied by amide hydrogen exchange/mass spectrometry. Unfolding was studied by destabilizing the protein in guanidine hydrochloride (GdHCl) or urea, pulse-labeling with 2H2O and analyzing the intact protein by HPLC electrospray ionization mass spectrometry. Bimodal isotope patterns were found in the mass spectra of the labeled protein, indicating two-state unfolding behavior.
View Article and Find Full Text PDF