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  1. Article ; Online: Formation, reactivity, and detection of protein sulfenic acids.

    Kettenhofen, Nicholas J / Wood, Matthew J

    Chemical research in toxicology

    2010  Volume 23, Issue 11, Page(s) 1633–1646

    Abstract: It has become clear in recent decades that the post-translational modification of protein cysteine residues is a crucial regulatory event in biology. Evidence supports the reversible oxidation of cysteine thiol groups as a mechanism of redox-based signal ...

    Abstract It has become clear in recent decades that the post-translational modification of protein cysteine residues is a crucial regulatory event in biology. Evidence supports the reversible oxidation of cysteine thiol groups as a mechanism of redox-based signal transduction, while the accumulation of proteins with irreversible thiol oxidations is a hallmark of stress-induced cellular damage. The initial formation of cysteine-sulfenic acid (SOH) derivatives, along with the reactive properties of this functional group, serves as a crossroads whereby the local redox environment may dictate the progression of either regulatory or pathological outcomes. Protein-SOH are established as transient intermediates in the formation of more stable cysteine oxidation products both under basal conditions and in response to several redox-active extrinsic compounds. This review details both direct and multistep chemical routes proposed to generate protein-SOH, the spectrum of secondary reactions that may follow their initial formation and the arsenal of experimental tools available for their detection. Pioneering studies that have provided a framework for our current understanding of protein-SOH as well as state-of-the-art proteomic strategies designed for global assessments of this post-translational modification are highlighted.
    MeSH term(s) Cysteine/chemistry ; Oxidation-Reduction ; Proteins/chemistry ; Proteomics ; Signal Transduction ; Sulfenic Acids/chemistry ; Sulfhydryl Compounds/chemistry
    Chemical Substances Proteins ; Sulfenic Acids ; Sulfhydryl Compounds ; Cysteine (K848JZ4886)
    Language English
    Publishing date 2010-09-16
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 639353-6
    ISSN 1520-5010 ; 0893-228X
    ISSN (online) 1520-5010
    ISSN 0893-228X
    DOI 10.1021/tx100237w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Activation and inhibition of soluble guanylyl cyclase by S-nitrosocysteine: involvement of amino acid transport system L.

    Riego, Joseph A / Broniowska, Katarzyna A / Kettenhofen, Nicholas J / Hogg, Neil

    Free radical biology & medicine

    2009  Volume 47, Issue 3, Page(s) 269–274

    Abstract: In this study the mechanism by which S-nitrosocysteine (CysNO) activates soluble guanylyl cyclase (sGC) has been investigated. CysNO is the S-nitrosated derivative of the amino acid cysteine and has previously been shown to be transported into various ... ...

    Abstract In this study the mechanism by which S-nitrosocysteine (CysNO) activates soluble guanylyl cyclase (sGC) has been investigated. CysNO is the S-nitrosated derivative of the amino acid cysteine and has previously been shown to be transported into various cell types by amino acid transport system L. Here we show, using both neuroblastoma and pulmonary artery smooth muscle cells, that CysNO stimulates cGMP formation at low concentrations, but this effect is lost at higher concentrations. Stimulation of cGMP accumulation occurs only after its transport into the cell and subsequent flavoprotein reductase-mediated metabolism to form nitric oxide (NO). Consequently, CysNO can be regarded as a cell-targeted NO-releasing agent. However, CysNO also functions as an NO-independent thiol-modifying agent and can compromise cellular antioxidant defenses in a concentration-dependent manner. The observed biphasic nature of CysNO-dependent cGMP accumulation seems to be due to these two competing mechanisms. At higher concentrations, CysNO probably inactivates guanylyl cyclase through modification of an essential thiol group on the enzyme, either directly or as a result of a more generalized oxidative stress. We show here that higher concentrations of CysNO can increase cellular S-nitrosothiol content to nonphysiological levels, deplete cellular glutathione, and inhibit cGMP formation in parallel. Although the inhibition of sGC by S-nitrosation has been suggested as a mechanism of nitrovasodilator tolerance, in the case of CysNO, it seems to be more a reflection of a generalized oxidative stress placed upon the cell by the nonphysiological levels of intracellular S-nitrosothiol generated upon CysNO exposure.
    MeSH term(s) Amino Acid Transport System L/metabolism ; Cell Line, Tumor ; Cells, Cultured ; Cyclic GMP/metabolism ; Cysteine/analogs & derivatives ; Cysteine/metabolism ; Enzyme Activation ; Guanylate Cyclase/genetics ; Guanylate Cyclase/metabolism ; Humans ; Myocytes, Smooth Muscle/enzymology ; Myocytes, Smooth Muscle/pathology ; Neuroblastoma/enzymology ; Neuroblastoma/pathology ; Nitric Oxide/metabolism ; Oxidative Stress ; Pulmonary Artery/pathology ; S-Nitrosothiols/metabolism
    Chemical Substances Amino Acid Transport System L ; S-Nitrosothiols ; Nitric Oxide (31C4KY9ESH) ; S-nitrosocysteine (926P2322P4) ; Guanylate Cyclase (EC 4.6.1.2) ; Cyclic GMP (H2D2X058MU) ; Cysteine (K848JZ4886)
    Language English
    Publishing date 2009-05-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 807032-5
    ISSN 1873-4596 ; 0891-5849
    ISSN (online) 1873-4596
    ISSN 0891-5849
    DOI 10.1016/j.freeradbiomed.2009.04.027
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: In-gel detection of S-nitrosated proteins using fluorescence methods.

    Kettenhofen, Nicholas J / Wang, Xunde / Gladwin, Mark T / Hogg, Neil

    Methods in enzymology

    2008  Volume 441, Page(s) 53–71

    Abstract: Gel-based detection of protein S-nitrosothiols has relied on the biotin-switch method. This method attempts to replace the nitroso group with a biotin label to allow detection and isolation of S-nitrosated proteins and has been used extensively in the ... ...

    Abstract Gel-based detection of protein S-nitrosothiols has relied on the biotin-switch method. This method attempts to replace the nitroso group with a biotin label to allow detection and isolation of S-nitrosated proteins and has been used extensively in the literature. This chapter describes a modification of this method that differs from the original in two major ways. First, it uses a combination of copper ions and ascorbate to achieve selective reduction of the S-nitrosothiol. Second, it replaces the biotin label with fluorescent cyanine dyes in order to directly observe the modified proteins in-gel and perform comparative studies using difference gel electrophoresis analysis in two dimensions.
    MeSH term(s) Animals ; Gels ; Humans ; Nitrosation ; Proteins/analysis ; Proteins/chemistry ; S-Nitrosothiols/analysis ; S-Nitrosothiols/chemistry ; Spectrometry, Fluorescence/methods
    Chemical Substances Gels ; Proteins ; S-Nitrosothiols
    Language English
    Publishing date 2008-05-23
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ISSN 0076-6879
    ISSN 0076-6879
    DOI 10.1016/S0076-6879(08)01204-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Copper dependence of the biotin switch assay: modified assay for measuring cellular and blood nitrosated proteins.

    Wang, Xunde / Kettenhofen, Nicholas J / Shiva, Sruti / Hogg, Neil / Gladwin, Mark T

    Free radical biology & medicine

    2008  Volume 44, Issue 7, Page(s) 1362–1372

    Abstract: Studies have shown that modification of critical cysteine residues in proteins leads to the regulation of protein function. These modifications include disulfide bond formation, glutathionylation, sulfenic and sulfinic acid formation, and S-nitrosation. ... ...

    Abstract Studies have shown that modification of critical cysteine residues in proteins leads to the regulation of protein function. These modifications include disulfide bond formation, glutathionylation, sulfenic and sulfinic acid formation, and S-nitrosation. The biotin switch assay was developed to specifically detect protein S-nitrosation (S. R. Jaffrey et al., Nat. Cell Biol. 3:193-197; 2001). In this assay, proteins are denatured with SDS in the presence of methyl methane thiosulfonate (MMTS) to block free thiols. After acetone precipitation or Sephadex G25 separation to remove excess MMTS, HPDP-biotin and 1 mM ascorbate are added to reduce the S-nitrosothiol bonds and label the reduced thiols with biotin. The proteins are then separated by nonreducing SDS PAGE and detected using either streptavidin-HRP or anti-biotin-HRP conjugate. Our examination of this labeling scheme has revealed that the extent of labeling depends on the buffer composition and, importantly, on the choice of metal-ion chelator (DTPA vs EDTA). Unexpectedly, using purified S-nitrosated albumin, we have found that "contaminating" copper is required for the ascorbate-dependent degradation of S-nitrosothiol; this is consistent with the fact that ascorbate itself does not rapidly reduce S-nitrosothiols. Removal of copper from buffers by DTPA and other copper chelators preserves approximately 90% of the S-nitrosothiol, whereas the inclusion of copper and ascorbate completely eliminates the S-nitrosothiol in the preparation and increases the specific biotin labeling. These biotin switch experiments were confirmed using triiodide-based and copper-based reductive chemiluminescence. Additional modifications of the assay using N-ethylmaleimide for thiol blockade, ferricyanide pretreatment to stabilize S-nitrosated hemoglobin, and cyanine dye labeling instead of biotin are presented for the measurement of cellular and blood S-nitrosothiols. These results indicate that degradation of S-nitrosothiol in the standard biotin switch assay is metal-ion dependent and that experimental variability in S-nitrosothiol yields using this assay occurs secondary to the inclusion of metal-ion chelators in reagents and variable metal-ion contamination of buffers and labware. The addition of copper to ascorbate allows for a simple assay modification that dramatically increases sensitivity while maintaining specificity.
    MeSH term(s) Biochemistry/methods ; Biotin/chemistry ; Bronchi/pathology ; Carbocyanines/pharmacology ; Copper/chemistry ; Copper/metabolism ; Cysteine/chemistry ; Epithelial Cells/cytology ; Free Radicals ; Hemoglobins/chemistry ; Humans ; Models, Biological ; Nitric Oxide/chemistry ; Nitrogen/chemistry ; S-Nitrosothiols/chemistry ; Sulfhydryl Compounds/chemistry
    Chemical Substances Carbocyanines ; Free Radicals ; Hemoglobins ; S-Nitrosothiols ; Sulfhydryl Compounds ; Nitric Oxide (31C4KY9ESH) ; Biotin (6SO6U10H04) ; Copper (789U1901C5) ; Cysteine (K848JZ4886) ; Nitrogen (N762921K75)
    Language English
    Publishing date 2008-01-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, N.I.H., Intramural
    ZDB-ID 807032-5
    ISSN 1873-4596 ; 0891-5849
    ISSN (online) 1873-4596
    ISSN 0891-5849
    DOI 10.1016/j.freeradbiomed.2007.12.032
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Proteomic methods for analysis of S-nitrosation.

    Kettenhofen, Nicholas J / Broniowska, Katarzyna A / Keszler, Agnes / Zhang, Yanhong / Hogg, Neil

    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences

    2007  Volume 851, Issue 1-2, Page(s) 152–159

    Abstract: This review discusses proteomic methods to detect and identify S-nitrosated proteins. Protein S-nitrosation, the post-translational modification of thiol residues to form S-nitrosothiols, has been suggested to be a mechanism of cellular redox signaling ... ...

    Abstract This review discusses proteomic methods to detect and identify S-nitrosated proteins. Protein S-nitrosation, the post-translational modification of thiol residues to form S-nitrosothiols, has been suggested to be a mechanism of cellular redox signaling by which nitric oxide can alter cellular function through modification of protein thiol residues. It has become apparent that methods that will detect and identify low levels of S-nitrosated protein in complex protein mixtures are required in order to fully appreciate the range, extent and selectivity of this modification in both physiological and pathological conditions. While many advances have been made in the detection of either total cellular S-nitrosation or individual S-nitrosothiols, proteomic methods for the detection of S-nitrosation are in relative infancy. This review will discuss the major methods that have been used for the proteomic analysis of protein S-nitrosation and discuss the pros and cons of this methodology.
    MeSH term(s) Animals ; Biological Assay ; Biological Transport ; Humans ; Molecular Weight ; Proteome/analysis ; Proteomics/methods ; S-Nitrosothiols/analysis ; S-Nitrosothiols/chemistry
    Chemical Substances Proteome ; S-Nitrosothiols
    Language English
    Publishing date 2007-02-25
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 1180823-8
    ISSN 1570-0232 ; 1387-2273
    ISSN 1570-0232 ; 1387-2273
    DOI 10.1016/j.jchromb.2007.02.035
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Role of S-nitrosothiol transport in the cardioprotective effects of S-nitrosocysteine in rat hearts.

    Hogg, Neil / Broniowska, Katarzyna A / Novalija, Jutta / Kettenhofen, Nicholas J / Novalija, Enis

    Free radical biology & medicine

    2007  Volume 43, Issue 7, Page(s) 1086–1094

    Abstract: The objective of this study was to determine if prior exposure of rat hearts to S-nitrosocysteine (CysNO) was able to provide protection against reperfusion injury. We probed NO release using the extracellular NO scavenger oxyhemoglobin (oxyHb), and we ... ...

    Abstract The objective of this study was to determine if prior exposure of rat hearts to S-nitrosocysteine (CysNO) was able to provide protection against reperfusion injury. We probed NO release using the extracellular NO scavenger oxyhemoglobin (oxyHb), and we examined the involvement of the amino acid transport system L (L-AT), a known transporter of CysNO, using the L-AT competitor, L-leucine (L-Leu). Isolated (9- to 12-week-old Wistar male) rat hearts (six to eight per group) were perfused with CysNO (10 microM) for 30 min with or without the L-AT competitor L-Leu (1 mM) before 30 min of ischemia. Cardiac function was assessed before, during, and after treatment and during 120 min of reperfusion after ischemia. Functional recovery (rate-pressure product) was significantly improved in the CysNO group compared to hearts in the CysNO+L-Leu group and the control group (p<0.05). Necrosis, measured by triphenyltetrazolium chloride staining, was significantly reduced in CysNO hearts (p<0.05) and this improvement was reversed by L-Leu. The NO scavenger oxyHb (20 microM) was perfused either concomitant with CysNO or just before ischemia. In neither case did oxyHb affect the cardioprotection afforded by CysNO. OxyHb alone, given in either time window, did not alter the course of ischemia-reperfusion injury. When nitrite was used in place of CysNO, no protective effects were observed. Perfusion with CysNO increased tissue S-nitrosothiol (RSNO) levels from an unmeasurable background to a value of about 15.7+/-4.1 pmol RSNO/mg protein, as measured by triiodide-based chemiluminescence in the presence and absence of mercury(II) chloride. In the presence of L-Leu, this value dropped to 0.4+/-0.3 pmol RSNO/mg protein. This study demonstrates that exposure to CysNO before ischemia increases tissue S-nitrosothiol levels, improves postischemic contractile dysfunction, and attenuates necrosis. The mechanism of cardioprotection requires the uptake of CysNO via the L-AT and does not seem to involve NO release either during CysNO exposure or during ischemia. This suggests that the protective effects of CysNO are mediated through the posttranslational modification of cellular proteins through an NO-independent transnitrosation mechanism.
    MeSH term(s) Animals ; Arrhythmias, Cardiac/etiology ; Arrhythmias, Cardiac/physiopathology ; Biological Transport ; Cardiotonic Agents/pharmacology ; Cysteine/analogs & derivatives ; Cysteine/pharmacology ; Leucine/pharmacology ; Male ; Myocardial Contraction ; Necrosis ; Nitric Oxide/metabolism ; Rats ; Rats, Wistar ; Reperfusion Injury/metabolism ; Reperfusion Injury/pathology ; Reperfusion Injury/prevention & control ; S-Nitrosothiols/metabolism ; S-Nitrosothiols/pharmacology ; Ventricular Dysfunction, Left/etiology ; Ventricular Dysfunction, Left/physiopathology
    Chemical Substances Cardiotonic Agents ; S-Nitrosothiols ; Nitric Oxide (31C4KY9ESH) ; S-nitrosocysteine (926P2322P4) ; Leucine (GMW67QNF9C) ; Cysteine (K848JZ4886)
    Language English
    Publishing date 2007-10-01
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 807032-5
    ISSN 1873-4596 ; 0891-5849
    ISSN (online) 1873-4596
    ISSN 0891-5849
    DOI 10.1016/j.freeradbiomed.2007.06.016
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Intracellular redox status affects transplasma membrane electron transport in pulmonary arterial endothelial cells.

    Merker, Marilyn P / Bongard, Robert D / Kettenhofen, Nicholas J / Okamoto, Yoshiyuki / Dawson, Christopher A

    American journal of physiology. Lung cellular and molecular physiology

    2001  Volume 282, Issue 1, Page(s) L36–43

    Abstract: Pulmonary arterial endothelial cells possess transplasma membrane electron transport (TPMET) systems that transfer intracellular reducing equivalents to extracellular electron acceptors. As one aspect of determining cellular mechanisms involved in one ... ...

    Abstract Pulmonary arterial endothelial cells possess transplasma membrane electron transport (TPMET) systems that transfer intracellular reducing equivalents to extracellular electron acceptors. As one aspect of determining cellular mechanisms involved in one such TPMET system in pulmonary arterial endothelial cells in culture, glycolysis was inhibited by treatment with iodoacetate (IOA) or by replacing the glucose in the cell medium with 2-deoxy-D-glucose (2-DG). TPMET activity was measured as the rate of reduction of the extracellular electron acceptor polymer toluidine blue O polyacrylamide. Intracellular concentrations of NADH, NAD(+), NADPH, and NADP(+) were determined by high-performance liquid chromatography of KOH cell extracts. IOA decreased TPMET activity to 47% of control activity concomitant with a decrease in the NADH/NAD(+) ratio to 34% of the control level, without a significant change in the NADPH/NADP(+) ratio. 2-DG decreased TPMET activity to 53% of control and decreased both NADH/NAD(+) and NADPH/NADP(+) ratios to 51% and 55%, respectively, of control levels. When lactate was included in the medium along with the inhibitors, the effects of IOA and 2-DG on both TPMET activity and the NADPH/NADP(+) ratios were prevented. The results suggest that cellular redox status is a determinant of pulmonary arterial endothelial cell TPMET activity, with TPMET activity more highly correlated with the poise of the NADH/NAD(+) redox pair.
    MeSH term(s) Animals ; Cattle ; Cell Membrane/metabolism ; Cells, Cultured ; Deoxyglucose/pharmacology ; Electron Transport/drug effects ; Endothelium, Vascular/cytology ; Endothelium, Vascular/physiology ; Intracellular Membranes/metabolism ; Iodoacetates/pharmacology ; Lactic Acid/pharmacology ; NAD/metabolism ; Oxidation-Reduction ; Pulmonary Artery/cytology ; Pulmonary Artery/physiology
    Chemical Substances Iodoacetates ; NAD (0U46U6E8UK) ; Lactic Acid (33X04XA5AT) ; Deoxyglucose (9G2MP84A8W)
    Language English
    Publishing date 2001-10-17
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 1013184-x
    ISSN 1522-1504 ; 1040-0605
    ISSN (online) 1522-1504
    ISSN 1040-0605
    DOI 10.1152/ajplung.00283.2001
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  8. Article: Pulmonary arterial endothelial cells affect the redox status of coenzyme Q0.

    Audi, Said H / Zhao, Hongtao / Bongard, Robert D / Hogg, Neil / Kettenhofen, Nicholas J / Kalyanaraman, Balaraman / Dawson, Christopher A / Merker, Marilyn P

    Free radical biology & medicine

    2003  Volume 34, Issue 7, Page(s) 892–907

    Abstract: The pulmonary endothelium is capable of reducing certain redox-active compounds as they pass from the systemic venous to the arterial circulation. This may have important consequences with regard to the pulmonary and systemic disposition and biochemistry ...

    Abstract The pulmonary endothelium is capable of reducing certain redox-active compounds as they pass from the systemic venous to the arterial circulation. This may have important consequences with regard to the pulmonary and systemic disposition and biochemistry of these compounds. Because quinones comprise an important class of redox-active compounds with a range of physiological, toxicological, and pharmacological activities, the objective of the present study was to determine the fate of a model quinone, coenzyme Q0 (Q), added to the extracellular medium surrounding pulmonary arterial endothelial cells in culture, with particular attention to the effect of the cells on the redox status of Q in the medium. Spectrophotometry, electron paramagnetic resonance (EPR), and high-performance liquid chromatography (HPLC) demonstrated that, when the oxidized form Q is added to the medium surrounding the cells, it is rapidly converted to its quinol form (QH2) with a small concentration of semiquinone (Q*-) also detectable. The isolation of cell plasma membrane proteins revealed an NADH-Q oxidoreductase located on the outer plasma membrane surface, which apparently participates in the reduction process. In addition, once formed the QH2 undergoes a cyanide-sensitive oxidation by the cells. Thus, the actual rate of Q reduction by the cells is greater than the net QH2 output from the cells.
    MeSH term(s) Animals ; Arteries/cytology ; Biotin/pharmacology ; Biotinylation ; Cattle ; Cell Membrane/metabolism ; Cells, Cultured ; Chromatography, High Pressure Liquid ; Dose-Response Relationship, Drug ; Electron Spin Resonance Spectroscopy ; Electrons ; Endothelium, Vascular/metabolism ; Free Radicals ; Lung/cytology ; Models, Chemical ; NADP ; Oxidation-Reduction ; Time Factors ; Ubiquinone/metabolism
    Chemical Substances Free Radicals ; Ubiquinone (1339-63-5) ; NADP (53-59-8) ; Biotin (6SO6U10H04)
    Language English
    Publishing date 2003-04-01
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 807032-5
    ISSN 1873-4596 ; 0891-5849
    ISSN (online) 1873-4596
    ISSN 0891-5849
    DOI 10.1016/s0891-5849(03)00025-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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