Poly(rC)-binding protein (PCBP1) is a multifunctional adaptor protein that can coordinate single-stranded nucleic acids and iron-glutathione complexes, altering the processing and transfer of these ligands through interactions with other proteins. Multiple phenotypes are ascribed to cells lacking PCBP1, but the relative contribution of RNA, DNA, or iron chaperone activity is not consistently clear. Here, we report the identification of amino acid residues required for iron coordination on each structural domain of PCBP1 and confirm the requirement of iron coordination for binding target proteins BolA2 and ferritin.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Cell Res
November 2020
Iron-containing proteins rely on the incorporation of a set of iron cofactors for activity. The cofactors must be synthesized or assembled from raw materials located within the cell. The chemical nature of this pool of raw material - referred to as the labile iron pool - has become clearer with the identification of micro- and macro-molecules that coordinate iron within the cell.
View Article and Find Full Text PDFRedox balance is essential for normal brain, hence dis-coordinated oxidative reactions leading to neuronal death, including programs of regulated death, are commonly viewed as an inevitable pathogenic penalty for acute neuro-injury and neurodegenerative diseases. Ferroptosis is one of these programs triggered by dyshomeostasis of three metabolic pillars: iron, thiols, and polyunsaturated phospholipids. This review focuses on: (1) lipid peroxidation (LPO) as the major instrument of cell demise, (2) iron as its catalytic mechanism, and (3) thiols as regulators of pro-ferroptotic signals, hydroperoxy lipids.
View Article and Find Full Text PDFHundreds of cellular proteins require iron cofactors for activity, and cells express systems for their assembly and distribution. Molecular details of the cytosolic iron pool used for iron cofactors are lacking, but iron chaperones of the poly(rC)-binding protein (PCBP) family play a key role in ferrous ion distribution. Here we show that, in cells and in vitro, PCBP1 coordinates iron via conserved cysteine and glutamate residues and a molecule of noncovalently bound glutathione (GSH).
View Article and Find Full Text PDF: To assess treatment outcomes in juvenile idiopathic arthritis (JIA)-associated uveitis and relapse rates upon discontinuation of immunomodulatory therapy (IMT). : Medical records of patients with JIA-associated uveitis seen at the University of Illinois at Chicago and the F.I.
View Article and Find Full Text PDFAcanthamoeba infections are difficult to diagnose and treat. We present a renal transplant patient who developed Acanthamoeba endophthalmitis on therapy with posaconazole and miltefosine for cutaneous acanthamobiasis. The patient was maintained on intracameral voriconazole injections, and oral azithromycin, fluconazole, and flucytosine.
View Article and Find Full Text PDFBMJ Open Ophthalmol
June 2017
Background/aims: The goals of this pilot study were (a) to demonstrate the feasibility of identifying patients with vision-threatening diabetic retinopathy (DR) in a provincial area of Myanmar and treating them with portable lasers and (b) to gather data specific to Myanmar to help design larger cross-sectional studies of DR prevalence in Myanmar.
Methods: 97 consecutive patients with diabetes mellitus (DM) were identified by local ophthalmologists over a period of 1 month in Pyinmana, Myanmar and were referred to the pilot screening programme. Patients' demographics were recorded and their eyes were examined.
Eukaryotic cells contain hundreds of metalloproteins that are supported by intracellular systems coordinating the uptake and distribution of metal cofactors. Iron cofactors include heme, iron-sulfur clusters, and simple iron ions. Poly(rC)-binding proteins are multifunctional adaptors that serve as iron ion chaperones in the cytosolic/nuclear compartment, binding iron at import and delivering it to enzymes, for storage (ferritin) and export (ferroportin).
View Article and Find Full Text PDFPurpose: To evaluate the microstructural features of cytomegalovirus (CMV) retinitis by spectral domain optical coherence tomography (OCT).
Methods: Subjects were patients with macula-involving CMV retinitis with OCT imaging. The leading edge of retinitis in the macula was identified based on fundus imaging, and OCT findings were longitudinally evaluated in three areas: within the area of active retinitis, at the leading edge of retinitis, and just beyond the leading edge of retinitis.
Cytomegalovirus (CMV) is a ubiquitous DNA herpes virus that causes significant morbidity and mortality in immunocompromised individuals. CMV retinitis is a potentially blinding manifestation of CMV infection that was commonly seen in advanced acquired immunodeficiency syndrome (AIDS) in the era before modern combination antiretroviral therapy era, but is also recognized in patients with immune deficiency from multiple causes. The advent of and advances in antiretroviral therapies for human immunodeficiency virus have decreased the incidence of CMV retinitis by over 90% among AIDS patients, and improved visual outcomes in those affected.
View Article and Find Full Text PDFPurpose: To identify whether there has been a decline in ocular toxoplasmosis at a tertiary uveitis practice.
Methods: Retrospective review of new patients at the University of Illinois Uveitis Service from 1973 to 2012.
Results: There were 6820 patients with adequate records for inclusion; 323 (4.
Metallomics
September 2016
The early discovery of the human Cu(+)-ATPases and their link to Menkes and Wilson's diseases brought attention to the unique role of these transporters in copper homeostasis. The characterization of bacterial Cu(+)-ATPases has significantly furthered our understanding of the structure, selectivity and transport mechanism of these enzymes, as well as their interplay with other elements of Cu(+) distribution networks. This review focuses on the structural-functional insights that have emerged from studies of bacterial Cu(+)-ATPases at the molecular level and how these observations have contributed to drawing up a comprehensive picture of cellular copper homeostasis.
View Article and Find Full Text PDFLittle is known about iron efflux transporters within bacterial systems. Recently, the participation of Bacillus subtilis PfeT, a P1B4-ATPase, in cytoplasmic Fe(2+) efflux has been proposed. We report here the distinct roles of mycobacterial P1B4-ATPases in the homeostasis of Co(2+) and Fe(2+) Mutation of Mycobacterium smegmatis ctpJ affects the homeostasis of both ions.
View Article and Find Full Text PDFListeria monocytogenes FrvA (Lmo0641) is critical for virulence in the mouse model and is an ortholog of the Bacillus subtilis Fur- and PerR-regulated Fe(II) efflux P1B4 -type ATPase PfeT. Previously, FrvA was suggested to protect against heme toxicity. Here, we demonstrate that an frvA mutant is sensitive to iron intoxication, but not to other metals.
View Article and Find Full Text PDFIron is an essential element for nearly all cells and limited iron availability often restricts growth. However, excess iron can also be deleterious, particularly when cells expressing high affinity iron uptake systems transition to iron rich environments. Bacillus subtilis expresses numerous iron importers, but iron efflux has not been reported.
View Article and Find Full Text PDFCopper is an important element in host-microbe interactions, acting both as a catalyst in enzymes and as a potential toxin. Cu(+)-ATPases drive cytoplasmic Cu(+) efflux and protect bacteria against metal overload. Many pathogenic and symbiotic bacteria contain multiple Cu(+)-ATPase genes within particular genetic environments, suggesting alternative roles for each resulting protein.
View Article and Find Full Text PDFBackground: Sarcoidosis is an idiopathic, multi-system, granulomatous disease with well-described ocular manifestations. However, other uveitic etiologies can manifest in a similar fashion, and ocular disease may precede systemic manifestations. Definitive diagnosis requires histologic confirmation of non-caseating granulomatous inflammation.
View Article and Find Full Text PDFObjective: To evaluate the safety and effectiveness of short-term, high-dose chlorambucil therapy in achieving long-term, drug-free remission in the treatment of sympathetic ophthalmia (SO).
Design: Retrospective case series.
Participants: Sixteen patients with SO treated with high-dose, short-term chlorambucil therapy between 1970 and 2010.