DOCSLIB.ORG

Convenient Preparation of Poly(L-Histidine) by the Direct Polymerization of L-Histidine Or Nim Benzyl-L-Histidine with Diphenylphosphoryl Azide

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Polymer Journal, Vol. 13, No. 12, pp 1151-1154 (1981) SHORT COMMUNICATION Convenient Preparation of Poly(L-histidine) by the Direct Polymerization of L-Histidine or Nim_Benzyl-L-histidine with Diphenylphosphoryl Azide Takumi NARUSE, Bun-ichiro NAKAJIMA, Akihiro TSUTSUMI, and Norio NISHI Department of Polymer Science, Faculty of Science, Hokkaido University, Nishi 8-chome, Kita 10-jo, Kita-ku, Sapporo 060, Japan. (Received August 14, 1981) KEY WORDS Polymerization I Diphenylphosphoryl Azide (DPPA) I L- Histidine I N'm-Benzyl-L-histidine I Poly(L-histidine) I Poly(N'm-benzyl-L­ histidine) I IR Spectrum I 13C NMR Spectrum I Intrinsic Viscosity I Poly(L-histidine) is a very interesting poly(a­ histidine) by the polymerization of L-histidine with amino acid) as a synthetic functional polymer or as iodine-phosphonic acid esters was unsuccessful. The a model for the functional biopolymer such as simplification of the synthetic route for poly(L­ enzymes. It is known, however, that poly(L­ histidine) is still necessary. histidine) can not be prepared by the Fuchs­ Diphenylphosphoryl azide (DPPA) has been used Farthing method 1 which is very popular for prepar­ as a convenient reagent for racemization-free pep­ ing poly(a-amino acid)s. A synthetic route with tide synthesis, since it was synthesized by Shioiri et several steps involving the synthesis of NCA (a­ a!. in 1972.6 Recently, we reported that this reagent amino acid N-carboxyanhydride) by the rather can also be used successfully for the polymerization classical Leuchs method/ have been used for the of amino acids or peptides. 7 -to A polypeptide can preparation ofpoly(L-histidine) as shown in Scheme easily be prepared by simply stirring the solution or I-(A)? Among the many successful attempts for the the suspension of amino acid or peptide in a suitable direct polycondensation of amino acids,4 •5 that of solvent with DPPA and a tertiary amine such as Guilly et a/. 5 for the one-step preparation ofpoly(L- triethylamine. One of the merits ofDPPA in peptide Bzl-Cl, Na Z-Cl (A) H-His-OH H-His(Bzl)-OH ->Z-His(Bzl)-OH NH3 NaOH PCI5 Polymerization ->(-COCI) Poly[His(Bzl)) NH3 . DPPA p I (H. ) (B) H-Hts-OH o y ts Base H-His(Bzl)-OH DPPA Poly[His(Bzl)) Base NH3 Scheme I. Synthetic routes of poly(L-histidine) (A) with the NCA method proposed by Patchonl.ik et al./ and (B) with DPPA method: Bzl, benzyl; Z, benzyloxycarbonyl. 1151 T. NARUSE et a/. synthesis is that the protection of imidazole group is In the present study, the one-step preparation of not necessary for the preparation of histidine­ poly(L-histidine) by the polymerization of L­ containing peptide/ 1 since the reaction proceeds via histidine with DPPA was investigated to simplify acyl azide12 similarly as in the case of the well­ the preparative method for poly(L-histidine). The known azide coupling method. polymerization of N im_benzyl-L-histidine to give 4000 3000 Wave Number (cm-1) Figure 1. Infrared absorption spectra ofpoly(L-histidine)s prepared by (a) DPPA method, and (b) NCA method.3 (a) crJ. ct3 Dioxane (b) 200 150 100 50 0 ppm from TMS Figure 2. 13C NMR spectra of poly(L-histidine)s in aqueous solution (pD 3) measured at 15.04 MHz: repetition time, 2s; (a) DPPA method; (b) NCA method. 3 1152 Polymer J., Vol. 13, No. 12, 1981 Convenient Preparation of Poly(L-histidine) with DPPA poly(N im_benzyl-L-histidine) has also been reported. ular weight peptides by the thin-layer chromatog­ The synthetic routes proposed in the present study raphies carried out on the mother liquor. However, are shown in Scheme I-(B). this yield of poly(L-histidine) is no worse than the To stirred suspensions of L-histidine (500 mg) in overall yield by the NCA method, since the syn­ DMSO or some other solvent were added DPPA thetic route via NCA requires several reaction steps. and triethylamine or another base. These mixtures The polymerizations of N im_benzyl-L-histidine were stirred for I h at 5-8°C followed by stirring were also investigated. The polymers were pre­ under various reaction conditions. Variation in the cipitated with 5% aqueous citric acid saturated with reactions was made by changing the amounts of sodium chloride. The sirupy precipitates were col­ solvent or reagent, reaction time and other reaction lected and washed with 5% aqueous citric acid conditions. The polymers were precipitated by the ( x 3), water ( x 3), warm 5% aqueous sodium bicar­ addition of saturated aqueous sodium chloride bonate ( x 3), and then with water ( x 3) by de­ (I 00 ml). The sirupy precipitates were collected and cantation. The residues were treated with ether to washed with water ( x 3), 5%,aqueous sodium bicar­ give the powders which were centrifuged, washed bonate ( x 3), and with water ( x 3), by decantation. with ether and then dried in vacuo. The results were The residues were treated with acetone to give the compared with each other as in the case of the powders which were centrifuged and washed with polymerizations of L-histidine. Consequently, the acetone ( x 3), methanol ( x 3), and ether ( x 1), and optimum reaction conditions were determined as then dried in vacuo. follow: Reaction time of one day at room tempera­ The IR and 13C NMR spectra of poly(L­ ture employing 0.6 ml of DMSO, 1.3 equiv mol of histidine) thus obtained were found to show the DPPA and 2.3 equiv mol of triethylamine to 300 mg same patterns as those of poly(L-histidine)3 pre­ of Nim_benzyl-L-histidine, followed by the reaction pared by the NCA method shown in Figures I and for another one day with the additional same 2. amount of solvent and reagents, and final heating at The reaction conditions, such as a reaction time 90°C for one hour at the end of the polymerization. of two days at room temperature or a reaction time Poly(N im_benzyl-L-histidine), which shows an in­ of six days at 5-8°C using I ml of DMSO, 1.3 trinsic viscosity ([ry]) of 0.12 in DCA at 25°C, can equiv mol of DPPA and 2.3 equiv mol of tri­ be obtained in a 46% yield by these optimum ethylamine to 500 mg of L-histidine, were con­ conditions. sidered to be most suitable. Under these reaction TheIR spectrum of poly(Nim_benzyl-L-histidine) conditions, poly(L-histidine) of [ry]=0.16 (in DCA thus obtained showed the same pattern as that of at 25°C) can be obtained in 24-25% yield directly poly(Nim_benzyl-L-histidine)3 prepared by NCA from L-histidine. The cause of the low yield is method as shown in Figure 3. considered due to the removal of very low molec- The amino acid analyses and the silica-gel thin- 3500 3000 1700 1500 1000 500 Wave Number (cm-1) Figure 3. Infrared absorption spectra of poly(N'm-benzyl-L-histidine)s prepared by (a) DPPA method, and (b) NCA method.3 Polymer J., Vol. 13, No. 12, 1981 1153 T. NARUSE et ai. layer chromatographies, carried out on two dif­ ported by a. Grant-in-Aid for Scientific Research ferent solvent systems (upper layer of 1-butanol­ from the Ministry of Educations, Science and acetic acid-water=4: I: 5 and 1-butanol-pyridine­ Culture of Japan. acetic acid-water= IS: 10:3: 12), for the acid hy­ drolysates ofpoly(L-histidine) and poly(Nim_benzyl­ REFERENCES L-histidine) showed only starting amino acids. This, along with the IR and NMR spectra, suggest the I. A. C. Farthing and R. J. W. Reynolds, Nature, 165, absence of side reactions induced by the Curtius 647 (1950). rearrangement which sometimes accompanies azide 2. H. Leuchs, Bericht., 37, 857 (1906). 3. A. Patchornik, A. Berger, and E. Katchalski, J. Am. coupling. Chern. Soc., 79, 5227 (1957). It was found that poly(L-histidine) and poly(Nim_ 4. F. Higashi, K. Sano, and H. Kakinoki, J. Poiym. benzyl-L-histidine) could be prepared directly from Sci., Poiym. Chern. Ed., 18, 1841 (1980). L-histidine and N im_benzyl-L-histidine, respectively, 5. L. L. Guilly, A. Brack, and G. Spach, Macromoi. by the DPPA method. The procedures for the Chern., 179, 2829 (1978). polymerization reaction or working up are simple 6. T. Shioiri, K. Ninomiya, and S. Yamada, J. Am. and easy. This novel method may be recommended Chern. Soc., 94, 6203 (1972). 7. N. Nishi, B. Nakajima, N. Hasebe, and J. Noguchi, as a convenient synthetic method for poly(L­ Int. J. Bioi. Macromoi., 2, 53 (1980). histidine). 8. B. Nakajima and N. Nishi, Poiym. J., 13, 183 (1981). Further investigation will be made for obtaining 9. B. Nakajima, K. Hirata, N. Nishi, and J. Noguchi, poly(L-histidine) of higher molecular weight in Int. J. Bioi. Macromoi., 3, 46 (1981). higher yield. In particular, polymerization re­ 10. N. Nishi, Peptide Chemistry 1978, Protein Research actions using polymer matrices must be investi­ Foundation, Osaka, 1979, p 151. 11. T. Shioiri and S. Yamada, Chern. Pharm. Bull., 22, gated in further detail. 859 (1974). 12. T. Shioiri and S. Yamada, Chern. Pharm. Bull., 22, Acknowledgment. The present work was sup- 855 (1974). 1154 Polymer J., Vol. 13, No. 12, 1981 .
Recommended publications
  • Diphenhydramine Hydrochloride (CASRN 147-24-0) in F344/N Rats

    Diphenhydramine Hydrochloride (CASRN 147-24-0) in F344/N Rats

    NATIONAL TOXICOLOGY PROGRAM Technical Report Series No. 355 TOXICOLOGY AND CARCINOGENESIS STUDIES OF DIPHENHYDRAMINE HYDROCHLORIDE (CAS NO. 147-24-0) IN F344/N RATS AND B6C3F1 MICE (FEED STUDIES) LJ.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service National Institutes of Health NTP ‘TECHNICAL REPORT ON THE TOXICOLOGY AND CARCINOGENESIS STUDIES OF DIPHENHYDRAMINE HYDROCHLORIDE (CAS NO. 147-24-0) IN F344/N RATS AND B6C3F1 MICE (FEED STUDIES) R. Melnick, Ph.D., Study Scientist NATIONAL TOXICOLOGY PROGRAM P.O. Box 12233 Research Triangle Park, NC 27709 September 1989 NTP TR 355 NIH Publication No. 89-2810 U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service National Institutes of Health CONTENTS PAGE ABSTRACT ................................................................ 3 EXPLANATION OF LEVELS OF EVIDENCE OF CARCINOGENIC ACTIVITY .................. 6 CONTRIBUTORS ............................................................ 7 PEERREVIEWPANEL ........................................................ 8 SUMMARY OF PEER REVIEW COMMENTS ......................................... 9 I. INTRODUCTION ........................................................ 11 I1. MATERIALS AND METHODS .............................................. 21 III. RESULTS ............................................................. 35 RATS ............................................................. 36 MICE ............................................................. 45 GENETIC TOXICOLOGY ............................................... 53 IV.
  • Role of Dietary Histidine in the Prevention of Obesity and Metabolic Syndrome

    Role of Dietary Histidine in the Prevention of Obesity and Metabolic Syndrome

    Open access Editorial Open Heart: first published as 10.1136/openhrt-2017-000676 on 1 July 2018. Downloaded from Role of dietary histidine in the prevention of obesity and metabolic syndrome James J DiNicolantonio,1 Mark F McCarty,2 James H OKeefe 1 To cite: DiNicolantonio JJ, HISTIDINE SUPPLEMENTATION AMELIORATES histidine dose dependently increases hypo- McCarty MF, OKeefe JH. Role of METABOLIC SYNDROME thalamic levels of histamine as well as hypo- dietary histidine in the prevention of obesity and A recent Chinese supplementation study, in thalamic activity of histidine decarboxylase, metabolic syndrome. Open Heart which obese middle-aged women diagnosed the enzyme which converts histidine to hista- 10 2018;5:e000676. doi:10.1136/ with metabolic syndrome received 12 weeks mine. Such administration also inhibits food openhrt-2017-000676 of supplemental histidine (2 g, twice daily) or consumption—an effect that is blocked in matching placebo, achieved remarkable find- animals pretreated with an irreversible inhib- 1 Accepted 24 April 2018 ings. Insulin sensitivity improved significantly itor of histidine decarboxylase. in the histidine-supplemented subjects, and Neuronal histamine release in the hypo- this may have been partially attributable to thalamus is subject to feedback regulation loss of body fat. Body mass index (BMI), waist by presynaptic H3 receptors. In rodent circumference and body fat declined in the studies, antagonists and inverse agonists for histidine-supplemented group relative to the these receptors have been shown to mark- placebo group; the average fat loss in the histi- edly amplify hypothalamic histamine levels, dine group was a robust 2.71 kg. Markers of suppress feeding, decrease body weight and systemic inflammation such as serum tumour enhance metabolic rate.11–15 Such agents may necrosis factor-alpha (TNF-α) and inter- have clinical potential for managing obesity.
  • Amino Acid Recognition by Aminoacyl-Trna Synthetases

    Amino Acid Recognition by Aminoacyl-Trna Synthetases

    www.nature.com/scientificreports OPEN The structural basis of the genetic code: amino acid recognition by aminoacyl‑tRNA synthetases Florian Kaiser1,2,4*, Sarah Krautwurst3,4, Sebastian Salentin1, V. Joachim Haupt1,2, Christoph Leberecht3, Sebastian Bittrich3, Dirk Labudde3 & Michael Schroeder1 Storage and directed transfer of information is the key requirement for the development of life. Yet any information stored on our genes is useless without its correct interpretation. The genetic code defnes the rule set to decode this information. Aminoacyl-tRNA synthetases are at the heart of this process. We extensively characterize how these enzymes distinguish all natural amino acids based on the computational analysis of crystallographic structure data. The results of this meta-analysis show that the correct read-out of genetic information is a delicate interplay between the composition of the binding site, non-covalent interactions, error correction mechanisms, and steric efects. One of the most profound open questions in biology is how the genetic code was established. While proteins are encoded by nucleic acid blueprints, decoding this information in turn requires proteins. Te emergence of this self-referencing system poses a chicken-or-egg dilemma and its origin is still heavily debated 1,2. Aminoacyl-tRNA synthetases (aaRSs) implement the correct assignment of amino acids to their codons and are thus inherently connected to the emergence of genetic coding. Tese enzymes link tRNA molecules with their amino acid cargo and are consequently vital for protein biosynthesis. Beside the correct recognition of tRNA features3, highly specifc non-covalent interactions in the binding sites of aaRSs are required to correctly detect the designated amino acid4–7 and to prevent errors in biosynthesis5,8.
  • Solutions to 7.012 Problem Set 1

    Solutions to 7.012 Problem Set 1

    MIT Biology Department 7.012: Introductory Biology - Fall 2004 Instructors: Professor Eric Lander, Professor Robert A. Weinberg, Dr. Claudette Gardel Solutions to 7.012 Problem Set 1 Question 1 Bob, a student taking 7.012, looks at a long-standing puddle outside his dorm window. Curious as to what was growing in the cloudy water, he takes a sample to his TA, Brad Student. He wanted to know whether the organisms in the sample were prokaryotic or eukaryotic. a) Give an example of a prokaryotic and a eukaryotic organism. Prokaryotic: Eukaryotic: All bacteria Yeast, fungi, any animial or plant b) Using a light microscope, how could he tell the difference between a prokaryotic organism and a eukaryotic one? The resolution of the light microscope would allow you to see if the cell had a true nucleus or organelles. A cell with a true nucleus and organelles would be eukaryotic. You could also determine size, but that may not be sufficient to establish whether a cell is prokaryotic or eukaryotic. c) What additional differences exist between prokaryotic and eukaryotic organisms? Any answer from above also fine here. In addition, prokaryotic and eukaryotic organisms differ at the DNA level. Eukaryotes have more complex genomes than prokaryotes do. Question 2 A new startup company hires you to help with their product development. Your task is to find a protein that interacts with a polysaccharide. a) You find a large protein that has a single binding site for the polysaccharide cellulose. Which amino acids might you expect to find in the binding pocket of the protein? What is the strongest type of interaction possible between these amino acids and the cellulose? Cellulose is a polymer of glucose and as such has many free hydroxyl groups.
  • Title Structure of the Human Histamine H1 Receptor Complex With

    Title Structure of the Human Histamine H1 Receptor Complex With

    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Kyoto University Research Information Repository Structure of the human histamine H1 receptor complex with Title doxepin. Shimamura, Tatsuro; Shiroishi, Mitsunori; Weyand, Simone; Tsujimoto, Hirokazu; Winter, Graeme; Katritch, Vsevolod; Author(s) Abagyan, Ruben; Cherezov, Vadim; Liu, Wei; Han, Gye Won; Kobayashi, Takuya; Stevens, Raymond C; Iwata, So Citation Nature (2011), 475(7354): 65-70 Issue Date 2011-07-07 URL http://hdl.handle.net/2433/156845 © 2011 Nature Publishing Group, a division of Macmillan Right Publishers Limited. Type Journal Article Textversion author Kyoto University Title: Structure of the human histamine H1 receptor in complex with doxepin. Authors Tatsuro Shimamura 1,2,3*, Mitsunori Shiroishi 1,2,4*, Simone Weyand 1,5,6, Hirokazu Tsujimoto 1,2, Graeme Winter 6, Vsevolod Katritch7, Ruben Abagyan7, Vadim Cherezov3, Wei Liu3, Gye Won Han3, Takuya Kobayashi 1,2‡, Raymond C. Stevens3‡and So Iwata1,2,5,6,8‡ 1. Human Receptor Crystallography Project, ERATO, Japan Science and Technology Agency, Yoshidakonoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. 2. Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-Ku, Kyoto 606-8501, Japan. 3. Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA. 4. Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. 5. Division of Molecular Biosciences, Membrane Protein Crystallography Group, Imperial College, London SW7 2AZ, UK. 6. Diamond Light Source, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE, UK.
  • Impaired Amino Acid and TCA Metabolism and Cardiovascular Autonomic Neuropathy Progression in Type 1 Diabetes

    Impaired Amino Acid and TCA Metabolism and Cardiovascular Autonomic Neuropathy Progression in Type 1 Diabetes

    Diabetes Volume 68, October 2019 2035 Impaired Amino Acid and TCA Metabolism and Cardiovascular Autonomic Neuropathy Progression in Type 1 Diabetes Anna V. Mathew,1 Mamta Jaiswal,2 Lynn Ang,2 George Michailidis,3 Subramaniam Pennathur,1,4 and Rodica Pop-Busui2 Diabetes 2019;68:2035–2044 | https://doi.org/10.2337/db19-0145 GENETICS/GENOMES/PROTEOMICS/METABOLOMICS While diabetes is characterized by hyperglycemia, nutri- Cardiovascular autonomic neuropathy (CAN) is a widely ent metabolic pathways like amino acid and tricarboxylic prevalent chronic diabetes complication that is character- acid (TCA) cycle are also profoundly perturbed. As gly- ized by impaired autonomic control of the cardiovascular cemic control alone does not prevent complications, we system (1). Although the initial prevalence of CAN in hypothesized that these metabolic disruptions are re- patients newly diagnosed with type 1 diabetes is low, later sponsible for the development and progression of di- prevalence after 15 years of diabetes increases to 35% in abetic cardiovascular autonomic neuropathy (CAN). We patients with type 1 diabetes and 60% in patients with performed standardized cardiovascular autonomic re- type 2 diabetes (1–4). CAN is an independent predictor of fl ex tests and targeted fasting plasma metabolomic chronic kidney disease progression and of cardiovascular analysis of amino acids and TCA cycle intermediates disease morbidity and mortality in patients with diabetes in subjects with type 1 diabetes and healthy control (5–8). CAN is also associated with an increased risk of subjects followed for 3 years. Forty-seven participants cardiac arrhythmias, silent myocardial ischemia, myocar- with type 1 diabetes (60% female and mean 6 SD age dial dysfunction, and sudden death (1,2,4,5,8).
  • Differential Pulse Polarographic Study of Simple and Mixed Complexes of Copper Ions with the Antidepressant Drug Imipramine and Glutamic Acid Or Histidine

    Differential Pulse Polarographic Study of Simple and Mixed Complexes of Copper Ions with the Antidepressant Drug Imipramine and Glutamic Acid Or Histidine

    Differential Pulse Polarographic Study of Simple and Mixed Complexes of Copper Ions with the Antidepressant Drug Imipramine and Glutamic Acid or Histidine M. KHODARI Department of Chemistry, Faculty of Science, South Valley University, Qena, Egypt Received 12 May 1997 The formation of binary and ternary complexes of glutamic acid or histidine and imipramine with Cu(II) has been examined using differential pulse Polarographie technique. The reduction of both simple and mixed systems is reversible and controlled by diffusion. The obtained results reveal the formation of mixed complexes. For the system Cu—Glu—Imip, one mixed complex was formed: Cu(Glu)(Imip)2 with stability constant log{/3i2} = 10.51, while the system Cu—His— Imip forms two complexes Cu(His)(Imip) and Cu(His)(Imip)2 with stabilities log{/?n} = 6.25 and log{/?i2} = 8.77, respectively. These experimental values were compared with the statistical ones. Mixed complexes are usually formed when the Histidine and other amino acids are involved in metal ion is present in a mixture of two or more com- copper(II) transport in blood and exchange interac­ plexing species in solution [1—3]. Different electro­ tions with serum albumin [13]. Imipramine is one of chemical techniques were applied to study such sys­ the most widely used drugs for the treatment of de­ tems [4—6]. The method of DeFord and Hume [7] as pression [14]. Hence their binary and ternary com­ extended by Schaap and McMasters [1] was used to plexes are of great interest. So the present work is calculate the formation constants of the mixed system aimed to study the expected formed complexes be­ using direct current Polarographie technique.
  • Identification of Histidine at the Catalytic Site of the Photosynthetic

    Identification of Histidine at the Catalytic Site of the Photosynthetic

    Proc. Natl. Acad. Sci. USA Vol. 91, pp. 704-708, January 1994 Biophysics Identification of histidine at the catalytic site of the photosynthetic oxygen-evolving complex (histidine labeling/pulsed electron paramagnetic resonance/manganese/photosystem II) XIAO-SONG TANG*, BRUCE A. DINER*, BARBARA S. LARSEN*, M. LANE GILCHRIST, JR.t, GARY A. LORIGANt, AND R. DAVID BRITTt *Central Research and Development Department, Experimental Station, P.O. Box 80173, E.I. DuPont de Nemours and Company, Wilmington, DE 19880; and tDepartment of Chemistry, University of California, Davis, CA 95616 Communicated by Pierre Joliot, October 26, 1993 (received for review September 13, 1993). ABSTRACT The molecular oxygen in our atmosphere is a nitrogen site. Electron-nuclear double resonance (ENDOR) product of a water-splitting reaction that occurs in the oxygen- studies of a thermophilic cyanobacterium grown on 15NO3 evolving complex ofphotosystem II ofoxygenic photosynthesis. showed 15N ENDOR transitions in the range 1-4 MHz (14). The catalytic core of the oxygen-evolving complex Is an ensem- These 15N ENDOR transitions most likely arise from the ble of four manganese atoms arranged in a cluster of undeter- same nitrogen class or classes that give rise to the 14N mined structure. The pulsed electron paramagnetic resonance ESEEM peaks. Neither the ESEEM nor the ENDOR exper- (EPR) technique of electron spin-echo envelope modulation iments provide a definitive chemical assignment to the origin (ESEEM) can be used to measure nuclear spin transitions of of the nitrogen spin transitions. To assign the origin of these nuclei magnetically coupled to paramagnetic metal centers of nitrogen spin transitions, we have incorporated into the PSII enzymes.
  • Amino Acid Requirements of the Free-Living Nematode Caenorhabditis Briggsae

    Amino Acid Requirements of the Free-Living Nematode Caenorhabditis Briggsae

    AMINO ACID REQUIREMENTS OF THE FREE-LIVING NEMATODE CAENORHABDITIS BRIGGSAE BY J. R. VANFLETEREN Instituut voor Dierkunde, Laboratoria voor Morfologie en Systematiek, RijksuniversiteitGent, Belgium Washed yeast ribosomes promote growth and reproduction of C. briggsae, even when supple- mented to the basal medium at dosages too low to provide the organisms with sufficient amounts of essential amino acids. Hence, a re-investigation of the amino acid requirements of C. briggsae by single and multiple omission of amino acids from the basal medium revealed unambiguously that arginine, histidine, lysine, tryptophan, phenylalanine, methionine, threonine, leucine, isoleucine and valine are not synthetized at levels to permit reproduction; they are called essential amino acids. The requirement for arginine and isoleucinehowever appears to be less clear-cut. On the contrary, evidence is presented that alanine, asparagine, cysteine, glutamate, glutamine, glycine, proline, serine and tryosine can be synthetized at adequate levels; they are called non- essential amino acids. In addition it was shown that multiple omission of the non-essential amino acids is not deleterious. This is believed to be an important step towards the development of a minimum essential medium (MEM) for growth and reproduction of C. briggsae. Sustained growth of the free-living nematode Caenorhabditis brigg.rae can be obtained on a chemically defined medium, supplemented with adequate levels of a proteinaceous growth factor. The most satisfactory, chemically defined medium hitherto reported (Buecher, Hansen & Yarwood, 1966), has been called C. brigg.iae Maintenance Medium (CbMM) and is now commercially available. CbMM is an extremely rich medium, being composed of 53 components, all present at high concentrations.
  • Amino Acid Catabolism: Urea Cycle the Urea Bi-Cycle Two Issues

    Amino Acid Catabolism: Urea Cycle the Urea Bi-Cycle Two Issues

    BI/CH 422/622 OUTLINE: OUTLINE: Protein Degradation (Catabolism) Digestion Amino-Acid Degradation Inside of cells Urea Cycle – dealing with the nitrogen Protein turnover Ubiquitin Feeding the Urea Cycle Activation-E1 Glucose-Alanine Cycle Conjugation-E2 Free Ammonia Ligation-E3 Proteosome Glutamine Amino-Acid Degradation Glutamate dehydrogenase Ammonia Overall energetics free Dealing with the carbon transamination-mechanism to know Seven Families Urea Cycle – dealing with the nitrogen 1. ADENQ 5 Steps 2. RPH Carbamoyl-phosphate synthetase oxidase Ornithine transcarbamylase one-carbon metabolism Arginino-succinate synthetase THF Arginino-succinase SAM Arginase 3. GSC Energetics PLP uses Urea Bi-cycle 4. MT – one carbon metabolism 5. FY – oxidases Amino Acid Catabolism: Urea Cycle The Urea Bi-Cycle Two issues: 1) What to do with the fumarate? 2) What are the sources of the free ammonia? a-ketoglutarate a-amino acid Aspartate transaminase transaminase a-keto acid Glutamate 1 Amino Acid Catabolism: Urea Cycle The Glucose-Alanine Cycle • Vigorously working muscles operate nearly anaerobically and rely on glycolysis for energy. a-Keto acids • Glycolysis yields pyruvate. – If not eliminated (converted to acetyl- CoA), lactic acid will build up. • If amino acids have become a fuel source, this lactate is converted back to pyruvate, then converted to alanine for transport into the liver. Excess Glutamate is Metabolized in the Mitochondria of Hepatocytes Amino Acid Catabolism: Urea Cycle Excess glutamine is processed in the intestines, kidneys, and liver. (deaminating) (N,Q,H,S,T,G,M,W) OAA à Asp Glutamine Synthetase This costs another ATP, bringing it closer to 5 (N,Q,H,S,T,G,M,W) 29 N 2 Amino Acid Catabolism: Urea Cycle Excess glutamine is processed in the intestines, kidneys, and liver.
  • A Study of the Renal Tubular Absorption and Glycine and Histidine in Dogs Following the Intravenous Infusion of Concetrated Solutions of These Amino Acids Daniel M

    A Study of the Renal Tubular Absorption and Glycine and Histidine in Dogs Following the Intravenous Infusion of Concetrated Solutions of These Amino Acids Daniel M

    Yale University EliScholar – A Digital Platform for Scholarly Publishing at Yale Yale Medicine Thesis Digital Library School of Medicine 1960 A study of the renal tubular absorption and glycine and histidine in dogs following the intravenous infusion of concetrated solutions of these amino acids Daniel M. Jones Yale University Follow this and additional works at: http://elischolar.library.yale.edu/ymtdl Recommended Citation Jones, Daniel M., "A study of the renal tubular absorption and glycine and histidine in dogs following the intravenous infusion of concetrated solutions of these amino acids" (1960). Yale Medicine Thesis Digital Library. 2755. http://elischolar.library.yale.edu/ymtdl/2755 This Open Access Thesis is brought to you for free and open access by the School of Medicine at EliScholar – A Digital Platform for Scholarly Publishing at Yale. It has been accepted for inclusion in Yale Medicine Thesis Digital Library by an authorized administrator of EliScholar – A Digital Platform for Scholarly Publishing at Yale. For more information, please contact [email protected]. YALE MEDICAL LIBRARY Manuscript Theses Unpublished theses submitted for the Master's and Doctor's degrees and deposited in the Yale Medical Library are to be used only with due regard to the rights of the authors. Bibliographical references may be noted, but passages must not be copied without permission of the authors, and without proper credit being given in subsequent written or published work. This thesis by has been used by the following persons, whose signatures attest their acceptance of the above restrictions. NAME AND ADDRESS DATE Digitized by the Internet Archive in 2017 with funding from The National Endowment for the Humanities and the Arcadia Fund https://archive.org/details/studyofrenaltubuOOjone A STUDY OF THE RENAL TUBULAR ABSORPTION AND EXCRETION OF GLYCINE AND HISTIDINE IN DOGS FOLLOWING THE INTRAVENOUS INFUSION OF CONCENTRATED SOLUTIONS OF THESE AMINO ACIDS DANIEL M.
  • Substitution of a Single Amino Acid (Aspartic Acid for Histidine)

    Substitution of a Single Amino Acid (Aspartic Acid for Histidine)

    Proc. Nail. Acad. Sci. USA Vol. 87, pp. 6868-6872, September 1990 Immunology Substitution of a single amino acid (aspartic acid for histidine) converts the functional activity of human complement C4B to C4A (thioester/immune complexes/C4 polymorphism) MICHAEL C. CARROLL*t, DEHMANHI M. FATHALLAH*t, LUIGI BERGAMASCHINI*§, ELIZABETH M. ALICOT*, AND DAVID E. ISENMAN¶ *Department of Pathology, Harvard Medical School and Children's Hospital, Boston, MA 02115; and $1Department of Biochemistry, University of Toronto, Toronto, ON, M5S 1A8 Canada Communicated by Elkan Blout, June 15, 1990 ABSTRACT The C4B isotype of the fourth component of ative or simply serves as a marker for a linked disease human complement (C4) displays 3- to 4-fold greater hemolytic susceptibility gene is not known. Nevertheless, C4 polymor- activity than does its other isotype C4A. This correlates with phism in general, and coexpression of the C4A and C4B differences in their covalent binding efficiencies to erythrocytes isotypes in particular, may ensure interaction with a wide coated with antibody and complement C1. C4A binds to a range of surfaces, similar to what has been proposed for class greater extent when C1 is on IgG immune aggregates. The I and II major histocompatibility molecules (19). differences in covalent binding properties correlate only with C4 protein is synthesized as a single polypeptide of 1706 amino acid changes between residues 1101 and 1106 (pro-C4 amino acids (13), which is processed (20) into three subunits numbering)-namely, Pro-1101, Cys-1102, Leu-1105, and (a, 95 kDa; ,3, 75 kDa; and y, 30 kDa) (21) before secretion.