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Abstract
Protein sulfenic acids play a key role in oxidative signal transduction of many biological and pathological processes; however, current chemical tools rely on visible fluorescence signals, limiting their utility to in vitro assays. We herein report reaction-based semiconducting polymer nanoprobes (rSPNs) with near-infrared absorption for in vivo photoacoustic (PA) imaging of protein sulfenic acids. rSPNs comprise an optically active semiconducting polymer as the core shielded with inert silica and poly(ethylene glycol) corona. The sulfenic acid reactive group (1,3-cyclohexanedione) is efficiently conjugated to the surface of nanoparticles via click chemistry. Such a nanostructure enables the specific recognition reaction between rSPNs and protein sulfenic acids without compromising the fluorescence and PA properties. In addition to in vitro tracking of the production of protein sulfenic acids in cancer cells under oxidative stress, rSPNs permit real-time PA and fluorescence imaging of protein sulfenic acids in tumors of living mice. This study thus not only demonstrates the first reaction-based PA probes with submolecular level recognition ability but also highlights the opportunities provided by hybrid nanoparticles for advanced molecular imaging.
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Affiliation(s)
- Yan Lyu
- School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637457
| | - Xu Zhen
- School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637457
| | - Yansong Miao
- School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637457
- School of Biological Sciences, Nanyang Technological University , Singapore 637551
| | - Kanyi Pu
- School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637457
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McGarry DJ, Shchepinova MM, Lilla S, Hartley RC, Olson MF. A Cell-Permeable Biscyclooctyne As a Novel Probe for the Identification of Protein Sulfenic Acids. ACS Chem Biol 2016; 11:3300-3304. [PMID: 27792307 DOI: 10.1021/acschembio.6b00742] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Reactive oxygen species act as important second messengers in cell signaling and homeostasis through the oxidation of protein thiols. However, the dynamic nature of protein oxidation and the lack of sensitivity of existing molecular probes have hindered our understanding of such reactions; therefore, new tools are required to address these challenges. We designed a bifunctional variant of the strained bicyclo[6.1.0]nonyne (BCN-E-BCN) that enables the tagging of intracellular protein sulfenic acids for biorthogonal copper-free click chemistry. In validation studies, BCN-E-BCN binds the sulfenylated form of the actin-severing protein cofilin, while mutation of the cognate cysteine residues abrogates its binding. BCN-E-BCN is cell permeable and reacts rapidly with cysteine sulfenic acids in cultured cells. Using different azide-tagged conjugates, we demonstrate that BCN-E-BCN can be used in various applications for the detection of sulfenylated proteins. Remarkably, cycloaddition of an azide-tagged fluorophore to BCN-E-BCN labeled proteins produced in vivo can be visualized by fluorescence microscopy to reveal their localization. These findings demonstrate a novel and multifaceted approach to the detection and trapping of sulfenic acids.
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Affiliation(s)
- David J McGarry
- Cancer Research UK Beatson Institute , Garscube Estate, Switchback Road, Glasgow G61 1BD, United Kingdom
| | - Maria M Shchepinova
- WestCHEM School of Chemistry, University of Glasgow , Glasgow G12 8QQ, United Kingdom
| | - Sergio Lilla
- Cancer Research UK Beatson Institute , Garscube Estate, Switchback Road, Glasgow G61 1BD, United Kingdom
| | - Richard C Hartley
- WestCHEM School of Chemistry, University of Glasgow , Glasgow G12 8QQ, United Kingdom
| | - Michael F Olson
- Cancer Research UK Beatson Institute , Garscube Estate, Switchback Road, Glasgow G61 1BD, United Kingdom
- Institute of Cancer Sciences, University of Glasgow , Glasgow G12 8QQ, United Kingdom
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Klomsiri C, Rogers LC, Soito L, McCauley AK, King SB, Nelson KJ, Poole LB, Daniel LW. Endosomal H2O2 production leads to localized cysteine sulfenic acid formation on proteins during lysophosphatidic acid-mediated cell signaling. Free Radic Biol Med 2014; 71:49-60. [PMID: 24657741 PMCID: PMC4064372 DOI: 10.1016/j.freeradbiomed.2014.03.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 03/10/2014] [Accepted: 03/14/2014] [Indexed: 12/17/2022]
Abstract
Lysophosphatidic acid (LPA) is a growth factor for many cells including prostate and ovarian cancer-derived cell lines. LPA stimulates H2O2 production which is required for growth. However, there are significant gaps in our understanding of the spatial and temporal regulation of H2O2-dependent signaling and the way in which signals are transmitted following receptor activation. Herein, we describe the use of two reagents, DCP-Bio1 and DCP-Rho1, to evaluate the localization of active protein oxidation after LPA stimulation by detection of nascent protein sulfenic acids. We found that LPA stimulation causes internalization of LPA receptors into early endosomes that contain NADPH oxidase components and are sites of H2O2 generation. DCP-Rho1 allowed visualization of sulfenic acid formation, indicative of active protein oxidation, which was stimulated by LPA and decreased by an LPA receptor antagonist. Protein oxidation sites colocalized with LPAR1 and the endosomal marker EEA1. Concurrent with the generation of these redox signaling-active endosomes (redoxosomes) is the H2O2- and NADPH oxidase-dependent oxidation of Akt2 and PTP1B detected using DCP-Bio1. These new approaches therefore enable detection of active, H2O2-dependent protein oxidation linked to cell signaling processes. DCP-Rho1 may be a particularly useful protein oxidation imaging agent enabling spatial resolution due to the transient nature of the sulfenic acid intermediate it detects.
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Affiliation(s)
- Chananat Klomsiri
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - LeAnn C Rogers
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Laura Soito
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Anita K McCauley
- Department of Biology, Wake Forest University, Winston-Salem, NC 27109, USA.
| | - S Bruce King
- Department of Chemistry, Wake Forest University, Winston-Salem, NC 27109, USA.
| | - Kimberly J Nelson
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Leslie B Poole
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Larry W Daniel
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
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Furdui CM, Poole LB. Chemical approaches to detect and analyze protein sulfenic acids. Mass Spectrom Rev 2014; 33:126-46. [PMID: 24105931 PMCID: PMC3946320 DOI: 10.1002/mas.21384] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/03/2013] [Accepted: 04/04/2013] [Indexed: 05/08/2023]
Abstract
Orchestration of many processes relying on intracellular signal transduction is recognized to require the generation of hydrogen peroxide as a second messenger, yet relatively few molecular details of how this oxidant acts to regulate protein function are currently understood. This review describes emerging chemical tools and approaches that can be applied to study protein oxidation in biological systems, with a particular emphasis on a key player in protein redox regulation, cysteine sulfenic acid. While sulfenic acids (within purified proteins or simple mixtures) are detectable by physical approaches like X-ray crystallography, nuclear magnetic resonance and mass spectrometry, the propensity of these moieties to undergo further modification in complex biological systems has necessitated the development of chemical probes, reporter groups and analytical approaches to allow for their selective detection and quantification. Provided is an overview of techniques that are currently available for the study of sulfenic acids, and some of the biologically meaningful data that have been collected using such approaches.
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Affiliation(s)
- Cristina M. Furdui
- Section on Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157
| | - Leslie B. Poole
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157
- Correspondence to: Leslie B. Poole, Department of Biochemistry, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157; ; telephone: 336-716-6711
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Picklo MJ, Idso JP, Jackson MI. S-Glutathionylation of hepatic and visceral adipose proteins decreases in obese rats. Obesity (Silver Spring) 2013; 21:297-305. [PMID: 23404913 PMCID: PMC3610808 DOI: 10.1002/oby.20002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 06/04/2012] [Indexed: 11/06/2022]
Abstract
UNLABELLED A number of clinical and biochemical studies demonstrate that obesity and insulin resistance are associated with increases in oxidative stress and inflammation. Paradoxically, insulin sensitivity can be enhanced by oxidative inactivation of cysteine residues of phosphatases, and inflammation can be reduced by S-glutathionylation with formation of protein-glutathione mixed disulfides (PSSG). Although oxidation of protein-bound thiols (PSH) is increased in multiple diseases, it is not known whether there are changes in PSH oxidation species in obesity. OBJECTIVE In this work, the hypothesis that obesity is associated with decreased levels of proteins containing oxidized protein thiols was tested. DESIGN AND METHODS The tissue levels of protein sulfenic acids (PSOH) and PSSG in liver, visceral adipose tissue, and skeletal muscle derived from glucose intolerant, obese-prone Sprague-Dawley rats were examined. RESULTS The data in this study indicate that decreases in PSSG content occurred in liver (44%) and adipose (26%) but not skeletal muscle in obese rats that were fed a 45% fat-calorie diet versus lean rats that were fed a 10% fat-calorie diet. PSOH content did not change in the tissue between the two groups. The activity of the enzyme glutaredoxin (GLRX) responsible for reversal of PSSG formation did not change in muscle and liver between the two groups. However, levels of GLRX1 were elevated 70% in the adipose tissue of the obese, 45% fat calorie-fed rats. CONCLUSION These are the first data to link changes in S-glutathionylation and GLRX1 to adipose tissue in the obese and demonstrate that redox changes in thiol status occur in adipose tissue as a result of obesity.
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Affiliation(s)
- Matthew J Picklo
- USDA-ARS Grand Forks Human Nutrition Research Center, Grand Forks, North Dakota, USA.
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Qian J, Wani R, Klomsiri C, Poole LB, Tsang AW, Furdui CM. A simple and effective strategy for labeling cysteine sulfenic acid in proteins by utilization of β-ketoesters as cleavable probes. Chem Commun (Camb) 2012; 48:4091-3. [PMID: 22430672 PMCID: PMC3568515 DOI: 10.1039/c2cc17868k] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
β-ketoesters are robust probes for labeling sulfenic acid (-SOH) proteins allowing quantitative cleavage of the tag for improved analysis of the labeled peptides by MS.
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Affiliation(s)
- Jiang Qian
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA
| | - Revati Wani
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA
| | - Chananat Klomsiri
- Department of Biochemistry, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA
| | - Leslie B. Poole
- Department of Biochemistry, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA
| | - Allen W. Tsang
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA
| | - Cristina M. Furdui
- Department of Internal Medicine, Section on Molecular Medicine, Wake Forest School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157, USA
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Huang CS, Zhu WP, Xu YF, Qian XH. [Chemical approaches for trapping protein thiols and their oxidative modification]. Yao Xue Xue Bao 2012; 47:280-290. [PMID: 22645750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Redox signal transduction, especially the oxidative modification of proein thiols, correlates with many diseases and becomes an expanding research area. However, there was rare method for quick and specific detection of protein thiols and their oxidative modification in living cells. In this article, we review the current chemical strategies for the detection and quantification of protein thiols and related cysteine oxidation. We also look into the future of the development of fluorescent probes for protein thiols and their potential application in the research of reactive cysteine proteomes and early detection of redox-related diseases.
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Affiliation(s)
- Chu-Sen Huang
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
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Block E, Dane AJ, Thomas S, Cody RB. Applications of direct analysis in real time mass spectrometry (DART-MS) in Allium chemistry. 2-propenesulfenic and 2-propenesulfinic acids, diallyl trisulfane S-oxide, and other reactive sulfur compounds from crushed garlic and other Alliums. J Agric Food Chem 2010; 58:4617-4625. [PMID: 20225897 DOI: 10.1021/jf1000106] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Through the use of direct analysis in real time mass spectrometry (DART-MS), 2-propenesulfenic acid, an intermediate long postulated as being formed when garlic ( Allium sativum ) is crushed, has been detected for the first time and determined by mass spectrometric methods to have a half-life of <1 s at room temperature. Two other key intermediates, 2-propenesulfinic acid and diallyl trisulfane S-oxide, have also been detected for the first time in volatiles from crushed garlic, along with allicin and related thiosulfinates, allyl alcohol, sulfur dioxide, propene, and pyruvate as coproducts. A commercial dietary supplement containing garlic powder, which was sampled after crushing, was found to contain alliin, methiin, and S-allylcysteine and produced allicin upon addition of water. DART-MS detection of 1-butenesulfenic acid from the ornamental A. siculum is also reported. (Z)-Propanethial S-oxide (onion lachrymatory factor), absent in garlic, is found to be formed from crushed elephant garlic ( Allium ampeloprasum ), consistent with the classification of this plant as a closer relative of leek than of garlic. Mixtures of thiosulfinates, lachrymatory thial S-oxides, and related compounds are directly observed from crushed leek ( Allium porrum ) and Chinese chive ( Allium tuberosum ). Disulfanes and polysulfanes are detected only when the Allium samples are heated, consistent with earlier conclusions that these are not primary products from cut or crushed alliums.
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Affiliation(s)
- Eric Block
- Department of Chemistry, University at Albany, SUNY, Albany, New York 12222, USA.
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Shetty V, Spellman DS, Neubert TA. Characterization by tandem mass spectrometry of stable cysteine sulfenic acid in a cysteine switch peptide of matrix metalloproteinases. J Am Soc Mass Spectrom 2007; 18:1544-51. [PMID: 17604642 PMCID: PMC1994715 DOI: 10.1016/j.jasms.2007.05.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 05/16/2007] [Accepted: 05/23/2007] [Indexed: 05/05/2023]
Abstract
Cysteine sulfenic acid (Cys-SOH) is an elusive intermediate in reactive oxygen species-induced oxidation reactions of many proteins such as peroxiredoxins and tyrosine phosphatases. Cys-SOH is proposed to play a vital role in catalytic and signaling functions. The formation of cysteine sulfinic acid (Cys-SO(2)H) and cysteine sulfonic acid (Cys-SO(3)H) has been implicated in the activation of matrix metalloproteinase-7 (MMP-7) and oxidation of thiol to cysteine sulfinic acid has been associated with the autolytic cleavage of MMP-7. We have examined the formation of cysteine sulfenic acid in a synthetic peptide PRCGVPDVA, which is a cysteine switch domain of MMP-7 and other matrix metalloproteases. We have prepared the cysteine sulfenic acid containing peptide, PRC(SOH)GVPDVA, by reaction with hydroxyl radicals generated by the Fenton reaction (Fe(+2)/H(2)O(2)). We characterized this modified peptide by tandem mass spectrometry and accurate mass measurement experiments. In addition, we used 7-chloro-4-nitrobenzo-2-oxa-1,3-diazol (NBD-Cl) reagent to form an adduct with PRC(SOH)GVPDVA to provide additional evidence for the viability of PRC(SOH)GVPDVA in solution. We also characterized an intramolecular cysteine sulfinamide cross-link product PRC[S(O)N]GVPDVA based on tandem mass spectrometry and accurate mass measurement experiments. These results contribute to the understanding of a proteolytic cleavage mechanism that is traditionally associated with MMP activation.
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Affiliation(s)
- Vivekananda Shetty
- Skirball Institute of Biomolecular Medicine and Department of Pharmacology, New York University School of Medicine, New York, New York 10016, USA
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Sun XZ, Vinci C, Makmura L, Han S, Tran D, Nguyen J, Hamann M, Grazziani S, Sheppard S, Gutova M, Zhou F, Thomas J, Momand J. Formation of disulfide bond in p53 correlates with inhibition of DNA binding and tetramerization. Antioxid Redox Signal 2003; 5:655-65. [PMID: 14580323 DOI: 10.1089/152308603770310338] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The p53 tumor suppressor protein is susceptible to oxidation, which prevents it from binding to its DNA response element. The goal of the current research was to determine the nature of the cysteine residue thiol oxidation that prevents p53 from binding its DNA target and its effect on p53 structure. Recombinant p53, purified in the presence of the reducing agent dithiothreitol (DTT), contains five free thiol groups on the surface of the protein. In the absence of DTT, p53 contains only four thiol groups, indicating that an average of one surface thiol group is readily susceptible to oxidation. Sulfite-mediated disulfide bond cleavage followed by reaction with 2-nitro-5-thiosulfobenzoate showed that oxidized p53 contains a single disulfide bond per monomer. By atomic force microscopy, we determined that reduced p53 binds to a double-stranded DNA containing the p53 promoter element of the MDM2 gene. The DNA-bound reduced p53 has an average cross-sectional diameter of 8.61 nm and a height of 4.12 nm. The amount of oxidized p53 that bound to the promoter element was ninefold lower, and it has an 18% larger average cross-sectional diameter. Electromobility shift assays showed that binding of oxidized p53 to DNA was enhanced upon addition of DTT, indicating that oxidation is reversible. The possibility that oxidized p53 contained significant amounts of sulfenic (-SOH), sulfinic (-SO2H), or sulfonic acid (-SO3H) was ruled out. Gel filtration chromatography indicated that oxidation increases the percentage of p53 monomers and high-molecular-weight oligomers (>1,000 kDa) relative to tetrameric p53. Protein modeling studies suggest that a mixed disulfide glutathione adduct on Cys182 could account for the observed stoichiometry of oxidized thiols and structural changes. The glutathione adduct may prevent proper helix-helix interaction within the DNA binding domain and contribute to tetramer dissociation.
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Affiliation(s)
- Xiu Zhu Sun
- Department of Chemistry and Biochemistry, California State University, Los Angeles, CA 90032, USA
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Lin SY, Nui DM, Tu CP, Cheng YD, Lin HL. Evidence of L-cysteinesulfinic acid in PKU neonatal hair roots, with disappearance after dietary control. Ultrastruct Pathol 2000; 24:351-2. [PMID: 11071575 DOI: 10.1080/019131200750035094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Affiliation(s)
- S Ferary
- University F. Rabelais, IRBI, UPRESA CNRS 6035, Tours, France
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Willett WS, Copley SD. Identification and localization of a stable sulfenic acid in peroxide-treated tetrachlorohydroquinone dehalogenase using electrospray mass spectrometry. Chem Biol 1996; 3:851-7. [PMID: 8939704 DOI: 10.1016/s1074-5521(96)90071-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Tetrachlorohydroquinone dehalogenase catalyzes the reductive dehalogenation of tetrachlorohydroquinone to trichlorohydroquinone and then to 2,6-dichlorohydroquinone. This enzyme undergoes oxidative damage during purification which causes it to form aberrant products. The damage is reversible by treatment with dithiothreitol. Possible types of oxidative damage include an inappropriate disulfide bond, a cysteine sulfenic acid, or a methionine sulfoxide. RESULTS Using electrospray liquid chromatography / mass spectrometry, we have demonstrated that oxidation of tetrachlorohydroquinone dehalogenase with H2O2 results in formation of a sulfenic acid at Cys13. Further oxidation to a sulfinic acid was also observed. CONCLUSIONS Oxidation of Cys 13 to a sulfenic acid prevents the normal reductive dehalogenation reaction from being completed. This finding is consistent with previous work which suggested that Cys 13 acts as a nucleophile during the conversion of tetrachlorohydroquinone to trichlorohydroquinone. The technique described for identification and localization of the cysteine sulfenic acid should be applicable to a wide variety of biological systems.
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Affiliation(s)
- W S Willett
- Department of Chemistry and Biochemistry and Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Boulder, CO 80309, USA.
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Shechter Y, Patchornik A, Burstein Y. Selective sulfenylation of tryptophan residues in alpha-lactalbumin of bovine milk. J Biol Chem 1974; 249:413-9. [PMID: 4855614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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Pohloudek-Fabini R, Kottke K, Friedrich F. [Splitting of organic disulfides in rhodan compounds and sulfenic acid rhodanides. 44. Organic compounds]. Pharmazie 1971; 26:283-6. [PMID: 5563059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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