Dylan W Domaille

Publications of Dylan W Domaille

• Calcium-dependent copper redistributions in neuronal cells revealed by a fluorescent copper sensor and X-ray fluorescence microscopy.

  Authors: Sheel C Dodani, Dylan W Domaille, Christine I Nam, Evan W Miller, Lydia A Finney, Stefan Vogt, Christopher J Chang

  Proceedings of the National Academy of Sciences of the United States of America. 03/2011; 108(15):5980-5.

  Dynamic fluxes of s-block metals like potassium, sodium, and calcium are of broad importance in cell signaling. In contrast, the concept of mobile transition metals triggered by cell activationDynamic fluxes of s-block metals like potassium, sodium, and calcium are of broad importance in cell signaling. In contrast, the concept of mobile transition metals triggered by cell activation remains insufficiently explored, in large part because metals like copper and iron are typically studied as static cellular nutrients and there are a lack of direct, selective methods for monitoring their distributions in living cells. To help meet this need, we now report Coppersensor-3 (CS3), a bright small-molecule fluorescent probe that offers the unique capability to image labile copper pools in living cells at endogenous, basal levels. We use this chemical tool in conjunction with synchotron-based microprobe X-ray fluorescence microscopy (XRFM) to discover that neuronal cells move significant pools of copper from their cell bodies to peripheral processes upon their activation. Moreover, further CS3 and XRFM imaging experiments show that these dynamic copper redistributions are dependent on calcium release, establishing a link between mobile copper and major cell signaling pathways. By providing a small-molecule fluorophore that is selective and sensitive enough to image labile copper pools in living cells under basal conditions, CS3 opens opportunities for discovering and elucidating functions of copper in living systems.

• Bacterial killing by dry metallic copper surfaces.

  Authors: Christophe Espírito Santo, Ee Wen Lam, Christian G Elowsky, Davide Quaranta, Dylan W Domaille, Christopher J Chang, Gregor Grass

  Applied and environmental microbiology. 02/2011; 77(3):794-802.

  Metallic copper surfaces rapidly and efficiently kill bacteria. Cells exposed to copper surfaces accumulated large amounts of copper ions, and this copper uptake was faster from dry copper than fromMetallic copper surfaces rapidly and efficiently kill bacteria. Cells exposed to copper surfaces accumulated large amounts of copper ions, and this copper uptake was faster from dry copper than from moist copper. Cells suffered extensive membrane damage within minutes of exposure to dry copper. Further, cells removed from copper showed loss of cell integrity. Acute contact with metallic copper surfaces did not result in increased mutation rates or DNA lesions. These findings are important first steps for revealing the molecular sensitive targets in cells lethally challenged by exposure to copper surfaces and provide a scientific explanation for the use of copper surfaces as antimicrobial agents for supporting public hygiene.

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• Mechanisms of contact-mediated killing of yeast cells on dry metallic copper surfaces.

  Authors: Davide Quaranta, Travis Krans, Christophe Espírito Santo, Christian G Elowsky, Dylan W Domaille, Christopher J Chang, Gregor Grass

  Applied and environmental microbiology. 01/2011; 77(2):416-26.

  Surfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacySurfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivate Candida albicans and Saccharomyces cerevisiae within minutes in a process called contact-mediated killing. Cellular copper ion homeostasis systems influenced the kinetics of contact-mediated killing in both organisms. Deregulated copper ion uptake through a hyperactive S. cerevisiae Ctr1p (ScCtr1p) copper uptake transporter in Saccharomyces resulted in faster inactivation of mutant cells than of wild-type cells. Similarly, lack of the C. albicans Crp1p (CaCrp1p) copper-efflux P-type ATPase or the metallothionein CaCup1p caused more-rapid killing of Candida mutant cells than of wild-type cells. Candida and Saccharomyces took up large quantities of copper ions as soon as they were in contact with copper surfaces, as indicated by inductively coupled plasma mass spectroscopy (ICP-MS) analysis and by the intracellular copper ion-reporting dye coppersensor-1. Exposure to metallic copper did not cause lethality through genotoxicity, deleterious action on a cell's genetic material, as indicated by a mutation assay with Saccharomyces. Instead, toxicity mediated by metallic copper surfaces targeted membranes in both yeast species. With the use of Live/Dead staining, onset of rapid and extensive cytoplasmic membrane damage was observed in cells from copper surfaces. Fluorescence microscopy using the indicator dye DiSBaC(2)(3) indicated that cell membranes were depolarized. Also, during contact-mediated killing, vacuoles first became enlarged and then disappeared from the cells. Lastly, in metallic copper-stressed yeasts, oxidative stress in the cytoplasm and in mitochondria was elevated.

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• Effect of cerebral amyloid angiopathy on brain iron, copper, and zinc in Alzheimer's disease.

  Authors: Matthew Schrag, Andrew Crofton, Matthew Zabel, Arshad Jiffry, David Kirsch, April Dickson, Xiao Wen Mao, Harry V Vinters, Dylan W Domaille, Christopher J Chang, Wolff Kirsch

  Journal of Alzheimer's disease : JAD. 12/2010; 24(1):137-49.

  Cerebral amyloid angiopathy (CAA) is a vascular lesion associated with Alzheimer's disease (AD) present in up to 95% of AD patients and produces MRI-detectable microbleeds in many of these patients.Cerebral amyloid angiopathy (CAA) is a vascular lesion associated with Alzheimer's disease (AD) present in up to 95% of AD patients and produces MRI-detectable microbleeds in many of these patients. It is possible that CAA-related microbleeding is a source of pathological iron in the AD brain. Because the homeostasis of copper, iron, and zinc are so intimately linked, we determined whether CAA contributes to changes in the brain levels of these metals. We obtained brain tissue from AD patients with severe CAA to compare to AD patients without evidence of vascular amyloid-β. Patients with severe CAA had significantly higher non-heme iron levels. Histologically, iron was deposited in the walls of large CAA-affected vessels. Zinc levels were significantly elevated in grey matter in both the CAA and non-CAA AD tissue, but no vascular staining was noted in CAA cases. Copper levels were decreased in both CAA and non-CAA AD tissues and copper was found to be prominently deposited on the vasculature in CAA. Together, these findings demonstrate that CAA is a significant variable affecting transition metals in AD.

• Visualizing ascorbate-triggered release of labile copper within living cells using a ratiometric fluorescent sensor.

  Authors: Dylan W Domaille, Li Zeng, Christopher J Chang

  Journal of the American Chemical Society. 02/2010; 132(4):1194-5.

  We present the synthesis, properties, and biological applications of Ratio-Coppersensor-1 (RCS1), a new water-soluble fluorescent sensor for ratiometric imaging of copper in living cells. RCS1We present the synthesis, properties, and biological applications of Ratio-Coppersensor-1 (RCS1), a new water-soluble fluorescent sensor for ratiometric imaging of copper in living cells. RCS1 combines an asymmetric BODIPY reporter and thioether-based ligand receptor to provide high selectivity and sensitivity for Cu(+) over other biologically relevant metal ions, including Cu(2+) and Zn(2+), a ca. 20-fold fluorescence ratio change upon Cu(+) binding, and visible excitation and emission profiles compatible with standard fluorescence microscopy filter sets. Live-cell confocal microscopy experiments show that RCS1 is membrane-permeable and can sense changes in the levels of labile Cu(+) pools within living cells by ratiometric imaging, including expansion of endogenous stores of exchangeable intracellular Cu(+) triggered by ascorbate stimulation in kidney and brain cells.

• Metals in neurobiology: probing their chemistry and biology with molecular imaging.

  Authors: Emily L Que, Dylan W Domaille, Christopher J Chang

  Chemical reviews. 06/2008; 108(5):1517-49.

• An ICT-based approach to ratiometric fluorescence imaging of hydrogen peroxide produced in living cells.

  Authors: Duangkhae Srikun, Evan W Miller, Dylan W Domaille, Christopher J Chang

  Journal of the American Chemical Society. 05/2008; 130(14):4596-7.

• Synthetic fluorescent sensors for studying the cell biology of metals.

  Authors: Dylan W Domaille, Emily L Que, Christopher J Chang

  Nature chemical biology. 04/2008; 4(3):168-75.

  Metals are essential for sustaining all forms of life, but alterations in their cellular homeostasis are connected to severe human disorders, including cancer, diabetes and neurodegenerativeMetals are essential for sustaining all forms of life, but alterations in their cellular homeostasis are connected to severe human disorders, including cancer, diabetes and neurodegenerative diseases. Fluorescent small molecules that respond to metal ions in the cell with appropriate selectivity and sensitivity offer the ability to probe physiological and pathological consequences of the cell biology of metals with spatial and temporal fidelity. Molecular imaging of normal and abnormal cellular metal ion pools using these new chemical tools provides a host of emerging opportunities for visualizing, in real time, aspects of metal accumulation, trafficking, and function or toxicity in living systems. This review presents a brief survey of available synthetic small-molecule sensor types for fluorescence detection of cellular metals.

• Convenient synthesis of 6,6-bicyclic malonamides: a new class of conformationally preorganized ligands for f-block ion binding.

  Authors: Bevin W Parks, Robert D Gilbertson, Dylan W Domaille, James E Hutchison

  The Journal of organic chemistry. 01/2007; 71(26):9622-7.

  A general synthetic approach was developed for the preparation of a series of 6,6-bicyclic malonamides, a class of ligands that provide a preorganized binding site for f-block ions (particularlyA general synthetic approach was developed for the preparation of a series of 6,6-bicyclic malonamides, a class of ligands that provide a preorganized binding site for f-block ions (particularly trivalent lanthanides). The approach described is convenient to introduce a variety of functional groups at the amide nitrogens to tune the properties of the ligand without altering the preorganized binding. Each of the ten derivatives (that represent a range of functionality, including R = alkyl, hydroxy, phenyl, ester, perfluorocarbon) reported here derives from a single, readily prepared dialdehyde intermediate. This intermediate is converted to the final products via reductive amination with an appropriately functionalized benzylamine, followed by hydrogenolysis and lactam formation. Because derivatization occurs late in the synthesis, the approach is general, requiring only modification of the purification procedures for each new derivative. To aid in the purification of the bicyclic malonamides, we report a novel complexation-based purification method that takes advantage of the high affinity of the ligand for f-block metals.

• Preparation and use of Coppersensor-1, a synthetic fluorophore for live-cell copper imaging.

  Authors: Evan W Miller, Li Zeng, Dylan W Domaille, Christopher J Chang

  Nature protocols. 02/2006; 1(2):824-7.

  Coppersensor-1 (CS1) is a small-molecule, membrane-permeable fluorescent dye for imaging labile copper pools in biological samples, including live cells. This probe, comprising a boron dipyrrometheneCoppersensor-1 (CS1) is a small-molecule, membrane-permeable fluorescent dye for imaging labile copper pools in biological samples, including live cells. This probe, comprising a boron dipyrromethene (BODIPY) chromophore coupled to a thioether-rich receptor, has a picomolar affinity for Cu+ with high selectivity over competing cellular metal ions. CS1 fluorescence increases up to 10-fold on binding to Cu+. In this protocol we describe the synthesis of CS1 and how to use this chemical tool to investigate intracellular levels of labile copper in cultured cells. The preparation of CS1 is anticipated to take 4-5 d, and imaging assays can be performed in 1-2 d with cultured cells.