DOCSLIB.ORG

Determinations of Proton Affinities of Methylated Cysteine and Serine Homologs

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Determinations of Proton Affinities of Methylated Cysteine and Serine Homologs W&M ScholarWorks Undergraduate Honors Theses Theses, Dissertations, & Master Projects 4-2019 Determinations of Proton Affinities of Methylated Cysteine and Serine Homologs Danielle Long Follow this and additional works at: https://scholarworks.wm.edu/honorstheses Part of the Analytical Chemistry Commons, and the Physical Chemistry Commons Recommended Citation Long, Danielle, "Determinations of Proton Affinities of Methylated Cysteine and Serine Homologs" (2019). Undergraduate Honors Theses. Paper 1351. https://scholarworks.wm.edu/honorstheses/1351 This Honors Thesis is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Undergraduate Honors Theses by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. Scanned with CamScanner Abstract Non-protein amino acids (NPAAs) are of interest to study for their potential to be incorporated into peptides and proteins, as well as for understanding their structure-energetics relationships. Studying these amino acids’ thermochemical properties such as their acidity and basicity allow for elucidation of the structure and bonding characteristics of these molecules. By examining these molecules in the gas-phase in mass spectrometers, we are able to determine their intrinsic thermodynamic properties without solvation effects. These thermochemical properties, in part, determine the structure, function and bonding of the molecules. This study focused on determining the proton affinities of methylated cysteine and serine homologs by using Cook’s extended kinetic method with orthogonal distance regression analysis in a triple quadrupole mass spectrometer. The NPAAs selected have been shown to mis- incorporate into small peptides, making it of interest to determine how these changes affect the structures and energetics of the peptide.1 The NPAAs studied included α-methylcysteine, L- penicillamine (gem-dimethyl cysteine), α-methylserine, and 3-methylthrenonine (gem-dimethyl serine), and their proton affinities were determined to be 923.7 ± 11 kJ/mol, 925 ± 15 kJ/mol, 932 ± 20 kJ/mol and 924 ± 15 kJ/mol, respectively. These experimental proton affinities are in excellent agreement with Boltmann-weighted computational proton affinities determined for these molecules. All of the methylated homologs had larger proton affinities than their respective protein amino acid, serine and cysteine, which have proton affinities of with proton affinities of 903 kJ/mol and 912 kJ/mol respectively.2 i Table of Contents Chapter 1: Introduction 1 1.1 Acid and Base Chemistry 1 1.2 Previous Non-Protein Amino Acid Studies 2 1.3 Kinetic Method 3 1.4 Quadrupole Mass Spectrometry 7 Chapter 2: Experimental Procedures 10 2.1 Experimentally Determined Proton Affinities 10 2.2 Computationally Determined Proton Affinities 12 Chapter 3: Results and Discussion 13 3.1 Computational Results 14 3.2 α-Methylcysteine Results 16 3.3 L-Penicillamine Results 20 3.4 α-Methylserine Results 24 3.5 3-Methylthreonine Results 28 3.6 Experimental Results Summary 32 Chapter 4: Conclusion and Future Work 34 References 35 ii Figures and Tables Figure 1: Kinetic Method Equation 5 Figure 2: Competitive Dissociation 6 Figure 3: Schematics of Quadrupole Mass Spectrometry 8 Figure 4: α-Methylcysteine 13 Figure 5: L-Penicillamine (dimethyl cysteine) 13 Figure 6: α-Methylserine 13 Figure 7: 3-Methylthreonine (dimethyl serine) 13 Figure 8: Yields of Peptide Produced by Valine, 3-Methylthreonine and L-Penicillamine 14 Table 1: Calculated Proton Affinities 14 Figure 9: Low Energy Conformers of Cysteine Homologs 15 Figure 10: Low Energy Conformers of Serine Homologs 15 Table 2: α-Methylcysteine Experimental Data 16 Figure 11: α-Methylcysteine Plot 1 17 Figure 12: α-Methylcysteine Plot 2 18 Figure 13: α-Methylcysteine Effective Temperature 19 Figure 14: α-Methylcysteine ODR 20 Table 3: L-Penicillamine Experimental Data 20 Figure 15: L-Penicillamine Plot 1 21 Figure 16 L-Penicillamine Plot 2 22 Figure 17: L-Penicillamine Effective Temperature 23 Figure 18: L-Penicillamine ODR 24 Table 4: α-Methylserine Experimental Data 24 iii Figure 19: α-Methylserine Plot 1 25 Figure 20: α-Methylserine Plot 2 26 Figure 21: α-Methylserine Effective Temperature 27 Figure 22: α-Methylserine ODR 28 Table 5: 3-Methylthreonine Experimental Data 28 Figure 23: 3-Methylthreonine Plot 1 29 Figure 24: 3-Methylthreonine Plot 2 30 Figure 253-Methylthreonine Effective Temperature 31 Figure 26: 3-Methylthreonine ODR 32 Table 6: Summary of Experimental versus Computational Results 33 Table 7: Proton Affinity of Cysteine and Serine 33 iv Acknowledgements I would to first thank Dr. J.C. Poutsma for his guidance and encouragement throughout my years in IonLab. I would also like to thank the members of IonLab for their support and collaboration. I would like to especially thank Izzy Owens, whose teamwork on this project was invaluable, as well as Zach Smith and Gwendyln Turner, for all their work in the computational aspects of the project. I would also like to thank Anwar Radwan for his continuous positive outlook and friendship throughout our time together in IonLab. I would like to thank both the College of William and Mary and the Charles Center for making this honors thesis possible. Lastly, I would like to thank the National Science Foundation for funding this project. v Chapter 1: Introduction 1.1 Acid Base Chemistry The acid-base properties of molecules are of interest to chemists for a variety of reasons. Thermodynamic properties such as acidity and basicity are partially responsible for governing the structure, bonding, and function of molecules. By determining these properties, we are able to get a clearer picture of the molecule’s overall structure and bonding behavior. These properties are useful in many different fields of study, ranging from medicine and biology to chemistry and nutrition.3-7 Acids and bases follow a typical reaction, which can be seen in (1), where a protonated conjugate acid (BH+) dissociates into a gaseous base (B) and a free proton (H+). !"#(%) → !(%) + "#; Δ" = -.; ∆0 = 0! (1) In Equation 1, proton affinity (PA) is the enthalpy change (Δ") for the reaction, and gas basicity (GB) is the Gibbs free energy (∆0) for the reaction. 8 This equation follows the Bronsted definition of acids and bases, where a base is a molecule that is capable of accepting a proton from a proton donor, while an acid is a molecule that is capable of donating a proton to a proton acceptor.9 Amino acids are of particular interest in acid-base chemistry study, as they are the building blocks of peptides and proteins. Although there are only twenty common protein amino acids that are incorporated into proteins in humans, there are many other non-protein amino acids that are of interest to study.10,11 Protein amino acids are those that are found in the main chains of peptides and proteins, while the non-protein amino acids are not found in protein main chains either because they do not have the specific transfer RNA and codon triplet needed, or because they do not have the correct post-translational modification.10 Studying these non-protein amino acids is important, as many of them have potential benefits in areas such as drug discovery, while others are toxic to 1 humans, secondary to their similar structures to protein amino acids.11 As these non-protein amino acids have similar structures to the common amino acids, it is of interest to see how these small differences in structure change the molecules bonding and acid-base properties. While acid-base reactions can be studied both in solution and in the gas-phase, gas-phase study is of interest due to the reactions solely depending on the acid-base strength of the reacting species, rather than on solvation effects.12 These reactions follow gas-phase acidity and gas-phase basicity scales, which are fundamentally different from the aqueous solution scale of pKa, due to solvation effects.12 On the gas-phase acidity/basicity scale, a stronger acid will have a smaller gas- phase acidity, and a stronger base will have a larger gas-phase basicity.12 Many of the experiments in gas-phase acid-base chemistry rely on the proton to evaluate the strength of the base. Acid-base reactions are based on the transfer of a proton and it is of interest to be able to measure the proton affinity of molecules to evaluate how strongly the proton will be attracted to a molecule of interest. This is discussed in detail in section 1.3, the kinetic method. 1.2 Previous Non-Protein Amino Acid Studies This lab has previously studied the thermochemical properties of various non-protein amino acids, including analogs of proline, lysine and arginine.5-7 All of these studies sought to determine how the thermochemical properties change with small structural changes to the amino acid.5-7 For proline, the study sought to determine the effects of increasing ring size on proton affinity.5 The proline analogs included L-azetidine-2-carboxylic acid, L-proline and L-pipecolic acid, which have 4-, 5-, and 6-membered ring nitrogen heterocycles, respectively.5 This study found that L-azetidine-2-carboylic acid, L-proline and L-pipecolic acid had proton affinities of 933 kJ/mol ± 6.3 kJ/mol, 941 kJ/mol ± 6.7 kJ/mol and 944 kJ/mol ± 6.7 kJ/mol, respectively.5 This 2 study was consistent with previous studies, which also found that increasing the size of a nitrogen heterocycle ring increased proton affinity.5,13,14 A second study by
Load more

Recommended publications
  • Dietary L-Citrulline Supplementation Modulates Nitric Oxide Synthesis and Anti-Oxidant Status of Laying Hens During Summer Seaso
    Uyanga et al. Journal of Animal Science and Biotechnology (2020) 11:103 https://doi.org/10.1186/s40104-020-00507-5 RESEARCH Open Access Dietary L-citrulline supplementation modulates nitric oxide synthesis and anti- oxidant status of laying hens during summer season Victoria A. Uyanga, Hongchao Jiao, Jingpeng Zhao, Xiaojuan Wang and Hai Lin* Abstract Background: L-citrulline (L-Cit), a non-protein amino acid, has been implicated in several physiological functions including anti-inflammatory, anti-oxidative, and hypothermic roles, however, there is a paucity of information with regards to its potential in poultry production. Methods: This study was designed to investigate the effects of dietary L-Cit supplementation on the production performance, nitric oxide production, and antioxidant status of laying hens during summer period. Hy-Line Brown laying hens (n = 288, 34 weeks old) were allotted to four treatment, 6 replicates of 12 chickens each. Dietary treatments of control (basal diets), 0.25%, 0.50% and 1.00% L-Cit supplementation were fed to chickens for eight (8) weeks. Production performance, free amino acid profiles, nitric oxide production, and antioxidant properties were measured. Blood samples were collected at the 4th and 8th weeks of the experiment. Results: Air temperature monitoring indicated an average daily minimum and maximum temperatures of 25.02 °C and 31.01 °C respectively. Dietary supplementation with L-Cit did not influence (P > 0.05) the production performance, and rectal temperature of laying hens. Egg shape index was increased (P < 0.05) with increasing levels of L-Cit. Serum-free content of arginine, citrulline, ornithine, tryptophan, histidine, GABA, and cystathionine were elevated, but taurine declined with L-Cit diets.
    [Show full text]
  • D-Penicillamine-Induced Status Dystonicus in a Patient with Wilson’S Disease: a Diagnostic & Therapeutic Challenge
    A. Satyasrinivas, et al. D-penicillamine-induced Status Dystonicus | Case Report D-penicillamine-induced Status Dystonicus in A Patient with Wilson’s Disease: A Diagnostic & Therapeutic Challenge A. Satyasrinivas*, Y.S. Kanni, N.Rajesh, M.SaiSravanthi, Vijay kumar Department of General Medicine, Kamineni Institute Of Medical Sciences, Narketpally 508254 Andhra Pradesh, India. DOI Name http://dx.doi.org/10.3126/jaim.v3i2.14066 Keywords Dystonia,Gabapentin Kayser-Fleischer ring, ABSTRACT Trientein hydrochloride, Wilson’s disease. Wilson's disease is an autosomal-recessive disorder of copper metabolism Citation resulting from the absence or dysfunction of a copper-transporting protein. A. Satyasrinivas, Y.S. Kanni, N.Rajesh, The disease is mainly seen in children, adolescents and young adults, and is M.SaiSravanthi, Vijay kumar. D-penicillamine- induced Status Dystonicus in A Patient with characterized by hepatobiliary, neurologic, psychiatric and ophthalmologic Wilson’s Disease: A Diagnostic & Therapeutic (Kayser-Fleischer rings) manifestations. Mechanism of status dystonicus in WD Challenge. Journal of Advances in Internal Medicine is not clear We present here a case study of Wil. son’s disease in 14 year old 2014;03(01):62-64. child with dystonia not responed with routine therapy. INTRODUCTION but patient had developed loose stools, difficulty in speaking and pronouncing linguals. With these compliants he was Wilson’s disease (WD), also known as hepatolenticular admitted in the hospital. On Radio imaging and ophthalmic degeneration was first described in 1912 by Kinnear Wilson as examination he was diagnosed as a case of Wilson’s disease progressive lenticular degeneration. WD is an inherited, fatal and was started with tablet calcium Pantothenate and neurological disorder accompanied by chronic liver disease tablets D-Penicillamine and was discharged.
    [Show full text]
  • D-Penicillamine)
    IMPORTANT PRESCRIBING INFORMATION: D-PENAMINE (D-penicillamine) Subject: Temporary importation of D-PENAMINE (D-penicillamine) 125 mg tablets to address shortage November 15, 2018 Dear Health Care Provider: Due to the shortage of penicillamine titratable tablets in the United States (U.S.) market, Mylan is coordinating with the U.S. Food and Drug Administration (FDA) to temporarily import penicillamine 125 mg tablets to address a critical drug shortage of penicillamine 250 mg titratable tablets. Mylan has initiated temporary importation of D-Penamine (D-penicillamine) tablets, 125 mg (not scored) distributed in Australia by Alphapharm Pty Limited, an FDA- inspected Mylan facility in Carole Park, Australia. At this time no other entity except Mylan is authorized by the FDA to import or distribute D- Penamine (D-penicillamine) tablets, 125 mg in the U.S. FDA has not approved Mylan’s D- Penamine (D-penicillamine) tablets, 125 mg in the United States. Please note that during this temporary period and only for this product lot, FDA does not intend to initiate regulatory action for violations of applicable section 582(b) requirements of the Federal Food, Drug, and Cosmetic Act. Effective immediately, and during this temporary period, Mylan will offer the following: Product name and Size Product code NDC code description (Bottle Count) D-PENAMINE (D- penicillamine) – 125mg tablets 100 tablets AUST R 14625 N/A for oral administration The U.S. product labeling should be followed as prescribed by the treating physician except patients should be instructed to take the correct multiple of D-Penamine 125 mg tablets to equal their currently prescribed Depen® dose.
    [Show full text]
  • Designing Peptidomimetics
    CORE Metadata, citation and similar papers at core.ac.uk Provided by UPCommons. Portal del coneixement obert de la UPC DESIGNING PEPTIDOMIMETICS Juan J. Perez Dept. of Chemical Engineering ETS d’Enginyeria Industrial Av. Diagonal, 647 08028 Barcelona, Spain 1 Abstract The concept of a peptidomimetic was coined about forty years ago. Since then, an enormous effort and interest has been devoted to mimic the properties of peptides with small molecules or pseudopeptides. The present report aims to review different approaches described in the past to succeed in this goal. Basically, there are two different approaches to design peptidomimetics: a medicinal chemistry approach, where parts of the peptide are successively replaced by non-peptide moieties until getting a non-peptide molecule and a biophysical approach, where a hypothesis of the bioactive form of the peptide is sketched and peptidomimetics are designed based on hanging the appropriate chemical moieties on diverse scaffolds. Although both approaches have been used in the past, the former has been more widely used to design peptidomimetics of secretory peptides, whereas the latter is nowadays getting momentum with the recent interest in designing protein-protein interaction inhibitors. The present report summarizes the relevance of the information gathered from structure-activity studies, together with a short review on the strategies used to design new peptide analogs and surrogates. In a following section there is a short discussion on the characterization of the bioactive conformation of a peptide, to continue describing the process of designing conformationally constrained analogs producing first and second generation peptidomimetics. Finally, there is a section devoted to review the use of organic scaffolds to design peptidomimetics based on the information available on the bioactive conformation of the peptide.
    [Show full text]
  • Proton Affinity Changes Driving Unidirectional Proton Transport In
    doi:10.1016/S0022-2836(03)00903-3 J. Mol. Biol. (2003) 332, 1183–1193 Proton Affinity Changes Driving Unidirectional Proton Transport in the Bacteriorhodopsin Photocycle Alexey Onufriev1, Alexander Smondyrev2 and Donald Bashford1* 1Department of Molecular Bacteriorhodopsin is the smallest autonomous light-driven proton pump. Biology, The Scripps Research Proposals as to how it achieves the directionality of its trans-membrane Institute, 10550 North Torrey proton transport fall into two categories: accessibility-switch models in Pines Road, La Jolla, CA 92037 which proton transfer pathways in different parts of the molecule are USA opened and closed during the photocycle, and affinity-switch models, which focus on changes in proton affinity of groups along the transport 2Schro¨dinger Inc., 120 West chain during the photocycle. Using newly available structural data, and Forty-Fifth Street, 32nd Floor adapting current methods of protein protonation-state prediction to the Tower 45, New York, NY non-equilibrium case, we have calculated the relative free energies of pro- 10036-4041, USA tonation microstates of groups on the transport chain during key confor- mational states of the photocycle. Proton flow is modeled using accessibility limitations that do not change during the photocycle. The results show that changes in affinity (microstate energy) calculable from the structural models are sufficient to drive unidirectional proton trans- port without invoking an accessibility switch. Modeling studies for the N state relative to late M suggest that small structural re-arrangements in the cytoplasmic side may be enough to produce the crucial affinity change of Asp96 during N that allows it to participate in the reprotonation of the Schiff base from the cytoplasmic side.
    [Show full text]
  • Effects of Penicillamine on Distribution of B6 Vitamers in Rat Urine
    J. Nutr. Sci. Vitaminol., 24, 1-7, 1978 EFFECTS OF PENICILLAMINE ON DISTRIBUTION OF B6 VITAMERS IN RAT URINE Toshihide KAJIWARA1 and Makoto MATSUDA2 1 Department of Orthopedic Surgery and 2Department of Biochemistry, Jikei University School of Medicine, Minato-ku, Tokyo 105, Janan (Received June 8, 1977) Summary The antivitamin B6 effect of DL and D-penicillamine has been studied in rats. A considerable elevation in the urinary excretion of vitamin B6 activity (pyridoxal and its thiazolidine derivative) has been shown as a parameter of B6 antagonism. Both DL and D-penicillamine have been shown to have an antivitamin B6 effect in rats, although that induced by the DL-form is considerably greater, as would be expected from previous studies. We suggest that B6 supplementation should be included in any long term penicillamine therapy, regardless of the isomer that is employed. Penicillamine (PeA) is now accepted as the treatment of choice of patients with WILSON'Sdisease because of its copper-chelating properties (1), and for cystinuric patients, in whom urinary cystine stone formation is prevented by the formation of a soluble PeA-cysteinemixed disulfide (2). It is currently under investigation in the treatment of rheumatoid arthritis, where it has been shown to produce various clinical improvements (3, 4). With the first description of its use as a drug with WILSON'sdisease (1), it was pointed out that certain toxic reactions might be expected in view of the works of Du VIGNEAUDet al. (5-7) who had shown that the inclusion of L-isomer of PeA (L-PeA) in the diet of rats caused vitamin B6 deficiency, resulting in inhibition of growth, reduced transaminase activity and abnormal excretion of xanthurenic acid following the administration of tryptophan: the D-isomer (D-PeA) appeared to have no toxic action under the conditions described (5, 8).
    [Show full text]
  • Proton Affinity of SO3
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Proton Affinity of SO3 Cynthia Ann Pommerening, Steven M. Bachrach, and Lee S. Sunderlin Department of Chemistry, Northern Illinois University, DeKalb, Illinois, USA ϩ Collision-induced dissociation (CID) of the radical cation H2SO4 gives the product pairs ϩ ϩ ϩ ϩ H2O SO3 and HO HSO3 with a 1:3 ratio that is essentially independent of collision energy. Statistical analysis of the two channels indicates that the proton affinity of HO is 3 Ϯ ϭ Ϯ 4 kJ/mol lower than that of SO3. This can be used to derive PA(SO3) 591 4 kJ/mol at 0 K and 596 Ϯ 4 kJ/mol at 298 K. Previously, Munson and Smith bracketed the proton affinity as PA(HBr) ϭ 584 kJ/mol Ͻ PA(SO ) Ͻ PA(CO) ϭ 594 kJ/mol. The threshold of 152 Ϯ 16 ϩ 3 kJ/mol for formation of H O ϩ SO indicates that the barrier to CID is small or nonexistent, 2 3 ϩ in contrast to the substantial barriers to decomposition for H3SO4 and H2SO4. (JAmSoc Mass Spectrom 1999, 10, 856–861) © 1999 American Society for Mass Spectrometry he development of extensive scales of proton this work provide an independent measurement of the ⌬ affinity (PA), gas basicity (GB), and acidity ( Ha) PA of SO3. values has provided a framework for the quanti- The gas-phase addition of H2OtoSO3 to form T ϭϪ⌬ tative understanding of ion properties. (PA H for sulfuric acid has a substantial barrier, as indicated by addition of a proton, GB ϭϪ⌬G for addition of a reaction rate measurements [4–6] and computational ⌬ ϭ⌬ proton, and Ha H for deprotonation.) The history results [7, 8].
    [Show full text]
  • Topical Photodynamic Therapy for Localized Scleroderma
    Acta Derm Venereol 2000; 80: 26±27 Topical Photodynamic Therapy for Localized Scleroderma SIGRID KARRER, CHRISTOPH ABELS, MICHAEL LANDTHALER and ROLF-MARKUS SZEIMIES Department of Dermatology, University of Regensburg, Regensburg, Germany Therapy of localized scleroderma is unsatisfactory, with MATERIAL AND METHODS numerous treatments being used that have only limited success Patients or considerable side-effects. The aim of this trial was to determine whether topical photodynamic therapy would be Five patients aged between 21 and 63 years with biopsy-proven effective in patients with localized scleroderma. Five patients localized scleroderma (morphoea) were studied. All patients had evidence of progressive disease, i.e. lesions showed an in¯ammatory with progressive disease, in whom conventional therapies had reaction and increase in size. In each patient the condition had failed, were treated by application of a gel containing 3% previously failed to respond to potent topical corticosteroids, systemic 5-aminolevulinic acid followed by irradiation with an incoherent therapy with penicillin and/or PUVA bath photochemotherapy. lamp (40 mW/cm2, 10 J/cm2). The treatment was performed Patients were required to discontinue all therapy at least 4 weeks once or twice weekly for 3 ± 6 months. In all patients the before study initiation. The most affected sclerotic plaque of each therapy was highly effective for sclerotic plaques, as measured patient was judged at baseline and then every 2 weeks during by a quantitative durometer score and a clinical skin score. The treatment. Sclerotic plaques were assessed by a clinical skin score (10) only side-effect was a transient hyperpigmentation of the and the durometer score (11).
    [Show full text]
  • Acid Dissociation Constant - Wikipedia, the Free Encyclopedia Page 1
    Acid dissociation constant - Wikipedia, the free encyclopedia Page 1 Help us provide free content to the world by donating today ! Acid dissociation constant From Wikipedia, the free encyclopedia An acid dissociation constant (aka acidity constant, acid-ionization constant) is an equilibrium constant for the dissociation of an acid. It is denoted by Ka. For an equilibrium between a generic acid, HA, and − its conjugate base, A , The weak acid acetic acid donates a proton to water in an equilibrium reaction to give the acetate ion and − + HA A + H the hydronium ion. Key: Hydrogen is white, oxygen is red, carbon is gray. Lines are chemical bonds. K is defined, subject to certain conditions, as a where [HA], [A−] and [H+] are equilibrium concentrations of the reactants. The term acid dissociation constant is also used for pKa, which is equal to −log 10 Ka. The term pKb is used in relation to bases, though pKb has faded from modern use due to the easy relationship available between the strength of an acid and the strength of its conjugate base. Though discussions of this topic typically assume water as the solvent, particularly at introductory levels, the Brønsted–Lowry acid-base theory is versatile enough that acidic behavior can now be characterized even in non-aqueous solutions. The value of pK indicates the strength of an acid: the larger the value the weaker the acid. In aqueous a solution, simple acids are partially dissociated to an appreciable extent in in the pH range pK ± 2. The a actual extent of the dissociation can be calculated if the acid concentration and pH are known.
    [Show full text]
  • The Renal Clearance of Amino Acids in Cystinuria
    The Renal Clearance of Amino Acids in Cystinuria J. C. Crawhall, … , C. J. Thompson, R. W. E. Watts J Clin Invest. 1967;46(7):1162-1171. https://doi.org/10.1172/JCI105609. Research Article The renal clearance of cystine, lysine, ornithine, arginine, and glycine has been compared with the simultaneously determined glomerular filtration rate in nine cystinuric patients. Five were studied before and after stabilization on penicillamine therapy, two were studied only while taking penicillamine, and two were studied only in the absence of penicillamine administration. The renal clearances of cysteine-penicillamine and of penicillamine disulfide were also determined in the patients who were taking the drug. Amino acids were determined by quantitative ion exchange chromatography, and the reliability of the method has been evaluated in terms of its reproducibility and of the recovery of known amounts of amino acids added to plasma and to urine. The plasma levels of cystine and of the basic amino acids were less than normal in all the patients. Cysteine- penicillamine and penicillamine disulfide were cleared by the kidney at rates similar to that of cystine. Two of the patients had glycine clearances that were considerably above the normal value. The renal clearance of cystine exceeded the glomerular filtration rate in six of the nine patients. The results form a continuum from values approximately equal to the glomerular filtration rate to values about twice this amount. The renal clearances of cystine and of the basic amino acids vary independently of one another in the disease. The significance of these results […] Find the latest version: https://jci.me/105609/pdf Journal of Clinical Investigation Vol.
    [Show full text]
  • Molecular Cloning and Functional Characterization of a Rainbow Trout Liver Oatp
    Erschienen in: Toxicology and Applied Pharmacology ; 280 (2014), 3. - S. 534-542 https://dx.doi.org/10.1016/j.taap.2014.08.031 Molecular cloning and functional characterization of a rainbow trout liver Oatp Konstanze Steiner a, Bruno Hagenbuch b,DanielR.Dietricha,⁎ a University of Konstanz, Human- and Environmental Toxicology, 78464 Konstanz, Germany b Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City 66160, KS, USA abstract Cyanobacterial blooms have an impact on the aquatic ecosystem due to the production of toxins (e.g. microcystins, MCs), which constrain fish health or even cause fish death. However the toxicokinetics of the most abundant toxin, microcystin LR (MC LR), are not yet fully understood. To investigate the uptake mechanism, the novel Oatp1d1 in rainbow trout (rtOatp1d1) was cloned, identified and characterized. The cDNA isolated from a clone library consisted of 2772 bp containing a 2115 bp open reading frame coding for a fi fi Keywords: 705 aa protein with an approximate molecular mass of 80 kDa. This sh speci c transporter belongs to the Microcystin OATP1 family and has most likely evolved from a common ancestor of OATP1C1. Real time PCR analysis showed Oatp that rtOatp1d1 is predominantly expressed in the liver, followed by the brain while expression in other organs Rainbow trout was not detectable. Transient transfection in HEK293 cells was used for further characterization. Like its Toxin transport human homologues OATP1A1, OATP1B1 and OATP1B3, rtOatp1d1 displayed multi specific transport including endogenous and xenobiotic substrates. Kinetic analyses revealed a Km value of 13.9 μMand13.4μMfor estrone 3 sulfate and methotrexate, respectively and a rather low affinity for taurocholate with a Km value of 103 μM.
    [Show full text]
  • Probing the Structure and Reactivity of Gaseous Ions a DISSERTATION
    Probing the Structure and Reactivity of Gaseous Ions A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY Matthew Michael Meyer IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Professor Steven R. Kass Febuary 2010 © Matthew Meyer 2010 Acknowledgements I want to express my gratitude to my advisor Dr. Steven Kass for the opportunity to work with him during my time at Minnesota. I am grateful for his willingness to share not only his vast knowledge of chemistry, but his approach to addressing problems. I also would like to acknowledge professors, John Anthony and Mark Meier for their mentorship while I was at the University of Kentucky that led me to a career in chemistry. Due to the broad nature of the research contained herein I am grateful for the contributions of the many collaborators I had the opportunity to work with while at Minnesota. In particular, I would like to thank Professors Richard O’Hair, Steven Blanksby, and Mark Johnson for their wiliness to allow me to spend time in their labs. During my course of studies I have also had the opportunities to interacts with a variety of other scientist that have contributed greatly to my development and completing this document, including Dr. Dana Reed, Dr. Mark Juhasz, Dr. Erin Speetzen, Dr. Nicole Eyet and Mr. Kris Murphy. I am also grateful for the support of my brother and sister through out this process. Lastly, I want to expresses gratitude to my parents for their support in all my pursuits and encouraging my incessant asking why probably since I could talk.
    [Show full text]