scholarly journals Lipid intermediates in the biosynthesis of the wall teichoic acid in Staphylococcus lactis I3

1972 ◽  
Vol 127 (1) ◽  
pp. 39-50 ◽  
Author(s):  
Helen Hussey ◽  
J. Baddiley
Keyword(s):  
Teichoic Acid ◽  
The Other ◽  
Pulse Labelling ◽  
Wall Teichoic Acid ◽  
Simultaneous Formation ◽  
Unidentified Lipid ◽  
The Poor ◽  
Enzyme Systems ◽  
Derivatives Of ◽  
Particulate Systems

1. Particulate enzyme systems have been prepared from Staphylococcus lactis I3 which effect the synthesis of wall teichoic acid (a polymer containing a repeating unit in which d-glycerol 1-phosphate is attached to the 4-position on N-acetylglucosamine 1-phosphate) from the nucleotide precursors CDP-glycerol and UDP-N-acetylglucosamine. By using nucleotides labelled with 32P and 14C it has been shown that the synthesis proceeds via lipid intermediates. 2. Two intermediates have been found. In one of these N-acetylglucosamine 1-phosphate is present, whereas in the other the repeating unit of the teichoic acid occurs. 3. The simultaneous formation of the teichoic acid, a poly-(N-acetylglucosamine 1-phosphate) and an unidentified lipid, together with the poor ability of most particulate systems to synthesize polymer and the instability of the lipid intermediates themselves, have interfered with pulse-labelling experiments. Nevertheless, the biosynthetic sequence has been elucidated. It is concluded that the intermediates are derivatives of undecaprenol phosphate.

scholarly journals Teichoic acid and lipid metabolism during sporulation of Bacillus megaterium KM

1982 ◽  
Vol 202 (2) ◽  
pp. 459-467 ◽  
Author(s):  
K Johnstone ◽  
F A Simion ◽  
D J Ellar
Keyword(s):  
Lipid Metabolism ◽  
Bacillus Megaterium ◽  
Exponential Growth ◽  
Teichoic Acid ◽  
Pulse Labelling ◽  
Lipid Phosphorus ◽  
Phospholipid Synthesis ◽  
Wall Teichoic Acid ◽  
Virtual Absence ◽  
Phosphorus Requirement

The biochemistry of teichoic acid and lipid metabolism has been studied during sporulation of Bacillus megaterium KM. Measurements of cell-wall and membrane teichoic acid have shown that net synthesis of these polymers ceases at the onset of sporulation. Pulse-labelling studies show that the period of asymmetric septation and forespore engulfment is marked by an initiation of turnover of membrane teichoic acid but not of wall teichoic acid. This is reflected in the presence of inner-membrane teichoic acid and the virtual absence of wall teichoic acid in dormant spores. The total amount of lipid phosphorus in the sporulating cell increases by 70% as a result of asymmetric septation and subsequent engulfment of the forespore. The phosphorus requirement for this synthesis is derived from a pool formed during exponential growth, which is not exchangeable with extracellular Pi during sporulation. These results suggest that during sporulation a proportion of the glycerol 3-phosphate produced by preferential degradation of membrane teichoic acid formed during exponential growth is used for phospholipid synthesis during sporulation.

scholarly journals Biosynthesis of the wall teichoic acid in Bacillus licheniformis

1972 ◽  
Vol 127 (1) ◽  
pp. 27-37 ◽  
Author(s):  
I. C. Hancock ◽  
J. Baddiley
Keyword(s):  
Bacillus Licheniformis ◽  
Teichoic Acid ◽  
Chain Extension ◽  
Pulse Labelling ◽  
Glycerol Phosphate ◽  
Wall Teichoic Acid ◽  
Anomeric Configuration ◽  
Glucose Phosphate ◽  
Chemical Studies ◽  
Two Stages

1. The biosynthesis of the wall teichoic acid, poly(glycerol phosphate glucose), has been studied with a particulate membrane preparation from Bacillus licheniformis A.T.C.C. 9945. The precursor CDP-glycerol supplies glycerol phosphate residues, whereas UDP-glucose supplies only glucose to the repeating structure of the polymer. 2. Synthesis proceeds through polyprenol phosphate derivatives, and chemical studies and pulse-labelling techniques show that the first intermediate is the phosphodiester, glucose polyprenol monophosphate. CDP-glycerol donates a glycerol phosphate residue to this to give a second intermediate, (glycerol phosphate glucose phosphate) polyprenol. 3. The glucose residue in the lipid intermediates has the β configuration, and chain extension in the synthesis of polymer occurs by transglycosylation with inversion of anomeric configuration at two stages.

Óscar Romero and the Politics of Sainthood

2011 ◽  
Vol 5 (3) ◽  
pp. 265-291
Author(s):  
Manuel A. Vasquez ◽  
Anna L. Peterson
Keyword(s):  
Human Rights ◽  
Civil War ◽  
El Salvador ◽  
The Other ◽  
Post Colonial ◽  
Holy See ◽  
The Poor ◽  
The Face ◽  
Crisis Of Modernity ◽  
The One

In this article, we explore the debates surrounding the proposed canonization of Archbishop Oscar Romero, an outspoken defender of human rights and the poor during the civil war in El Salvador, who was assassinated in March 1980 by paramilitary death squads while saying Mass. More specifically, we examine the tension between, on the one hand, local and popular understandings of Romero’s life and legacy and, on the other hand, transnational and institutional interpretations. We argue that the reluctance of the Vatican to advance Romero’s canonization process has to do with the need to domesticate and “privatize” his image. This depoliticization of Romero’s work and teachings is a part of a larger agenda of neo-Romanization, an attempt by the Holy See to redeploy a post-colonial and transnational Catholic regime in the face of the crisis of modernity and the advent of postmodern relativism. This redeployment is based on the control of local religious expressions, particularly those that advocate for a more participatory church, which have proliferated with contemporary globalization

Energy Approximation

2017 ◽  
Author(s):  
Philip Isett
Keyword(s):  
Main Lemma ◽  
The Other ◽  
Coarse Scale ◽  
Continuous Solutions ◽  
Material Derivative ◽  
Energy Variation ◽  
Energy Approximation ◽  
The Difference ◽  
Derivatives Of

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.

scholarly journals Depletion of Undecaprenyl Pyrophosphate Phosphatases Disrupts Cell Envelope Biogenesis in Bacillus subtilis

2016 ◽  
Vol 198 (21) ◽  
pp. 2925-2935 ◽  
Author(s):  
Heng Zhao ◽  
Yingjie Sun ◽  
Jason M. Peters ◽  
Carol A. Gross ◽  
Ethan C. Garner ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Transcriptional Repression ◽  
Cell Envelope ◽  
Turgor Pressure ◽  
Teichoic Acid ◽  
Lethal Gene ◽  
Genetic Redundancy ◽  
Wall Teichoic Acid ◽  
Content Type ◽  
Lipid Ii

ABSTRACTThe integrity of the bacterial cell envelope is essential to sustain life by countering the high turgor pressure of the cell and providing a barrier against chemical insults. InBacillus subtilis, synthesis of both peptidoglycan and wall teichoic acids requires a common C55lipid carrier, undecaprenyl-pyrophosphate (UPP), to ferry precursors across the cytoplasmic membrane. The synthesis and recycling of UPP requires a phosphatase to generate the monophosphate form Und-P, which is the substrate for peptidoglycan and wall teichoic acid synthases. Using an optimizedclusteredregularlyinterspacedshortpalindromicrepeat (CRISPR) system with catalytically inactive (“dead”)CRISPR-associated protein9(dCas9)-based transcriptional repression system (CRISPR interference [CRISPRi]), we demonstrate thatB. subtilisrequires either of two UPP phosphatases, UppP or BcrC, for viability. We show that a third predicted lipid phosphatase (YodM), with homology to diacylglycerol pyrophosphatases, can also support growth when overexpressed. Depletion of UPP phosphatase activity leads to morphological defects consistent with a failure of cell envelope synthesis and strongly activates the σM-dependent cell envelope stress response, includingbcrC, which encodes one of the two UPP phosphatases. These results highlight the utility of an optimized CRISPRi system for the investigation of synthetic lethal gene pairs, clarify the nature of theB. subtilisUPP-Pase enzymes, and provide further evidence linking the σMregulon to cell envelope homeostasis pathways.IMPORTANCEThe emergence of antibiotic resistance among bacterial pathogens is of critical concern and motivates efforts to develop new therapeutics and increase the utility of those already in use. The lipid II cycle is one of the most frequently targeted processes for antibiotics and has been intensively studied. Despite these efforts, some steps have remained poorly defined, partly due to genetic redundancy. CRISPRi provides a powerful tool to investigate the functions of essential genes and sets of genes. Here, we used an optimized CRISPRi system to demonstrate functional redundancy of two UPP phosphatases that are required for the conversion of the initially synthesized UPP lipid carrier to Und-P, the substrate for the synthesis of the initial lipid-linked precursors in peptidoglycan and wall teichoic acid synthesis.

scholarly journals On Professors and Poor People—A Jurisprudential Memoir

2007 ◽  
Vol 22 (2) ◽  
pp. 527-543
Author(s):  
Robert E. Rodes
Keyword(s):  
The Other ◽  
Poor People ◽  
Public Agency ◽  
The Public ◽  
The Poor ◽  
Low Degree ◽  
Preferential Option ◽  
The Subject ◽  
The Rich ◽  
Security Deposits

But let the brother of low degree glory in his high estate: and the rich, in that he is made low.—James 1:9-10I am starting this paper after looking at the latest of a series of e-mails regarding people who cannot scrape up the security deposits required by the local gas company to turn their heat back on. They keep shivering in the corners of their bedrooms or burning their houses down with defective space heaters. The public agency that is supposed to relieve the poor refuses to pay security deposits, and the private charities that pay deposits are out of money. A bill that might improve matters has passed one House of the Legislature, and is about to die in a committee of the other House. I have a card on my desk from a former student I ran into the other day. She works in the field of utility regulation, and has promised to send me more e-mails on the subject. I also have a pile of student papers on whether a lawyer can encourage a client illegally in the country to marry her boyfriend in order not to be deported.What I am trying to do with all this material is exercise a preferential option for the poor. I am working at it in a large, comfortable chair in a large, comfortable office filled with large, comfortable books, and a large—but not so comfortable—collection of loose papers. At the end of the day, I will take some of the papers home with me to my large, comfortable, and well heated house.

scholarly journals II. Compounds isomeric with the sulphocyanic ethers.—I. On the mustard oil of the ethyl series

1868 ◽  
Vol 16 ◽  
pp. 254-258
Keyword(s):  
Royal Society ◽  
The Other ◽  
Mustard Oil ◽  
Other Hand ◽  
Derivatives Of

The results of my researches on the chloroform-derivatives of the primary monamines, which, as I have shown, are isomeric with the nitriles, could not fail to direct my attention to allied groups of bodies, with the view of discovering similar isomerisms. In a note communicated to the Royal Society some months ago, I expressed the expectations which even then appeared to be justified in the following manner:—“In conclusion, I may be permitted to announce as everv probable the existence of a series of bodies isomeric with the sulphocyanides. Already M. Cloëz has shown that the action of chloride of cyanogen on ethylate of potassium gives rise to the formation of an ethylic cyanate possessing properties absolutely different from those belonging to the cyanate discovered by M. Wurtz. On comparing, on the other hand the properties of the methylic and ethylic sulphocyamdes with those of the sulphocyanides of allyl and phenyl, it can scarcely be doubted that we have here the representatives of two groups entirely different, and that the terms of the methyl- and ethyl-series which correspond to oil of mustard, and to the sulphocyanide of phenyl, still remain to be discovered. Experiments with which I am now engaged will show whether these bodies cannot be obtained by the action of the iodides of methyl and ethyl on sulphocyanide of silver."

The synthesis of the isomeric N-methyl derivatives of murexine

1981 ◽  
Vol 34 (8) ◽  
pp. 1739 ◽  
Author(s):  
CC Duke ◽  
JV Eichholzer ◽  
JK Macleod
Keyword(s):  
Imidazole Ring ◽  
The Other ◽  
Pharmacological Activities ◽  
Tautomeric Forms ◽  
Methyl Derivatives ◽  
Paramagnetic Ions ◽  
Nucella Emarginata ◽  
Derivatives Of

The two isomeric N-methyl derivatives of murexine have been synthesised by independent routes and shown to be different from an 'N- methylmurexine' reportedly isolated from the mollusc Nucella emarginata. 1H n.m.r. studies have shown a marked difference in the extent of binding to paramagnetic ions of the two N-methyl derivatives of murexine in water while pharmacological results show substantially different pharmacological activities of the two isomers. Both results can be rationalized in terms of the observed activities being associated with the presence of one or the other of the tautomeric forms of the imidazole ring.

Cleavage Reactions of 5-Arylazo Derivatives of 1-Methyl-2-benzyl-2-imidazolin-4-ones

1975 ◽  
Vol 30 (7-8) ◽  
pp. 603-605 ◽  
Author(s):  
Nazmi Abdel Latif Kassab ◽  
Abdel Hamid Harhash ◽  
Sanna Osman Abd Allah
Keyword(s):  
Sodium Hydroxide Solution ◽  
Aqueous Sodium Hydroxide ◽  
The Other ◽  
Ring Cleavage ◽  
Prolonged Heating ◽  
Aqueous Sodium Hydroxide Solution ◽  
Aqueous Sodium ◽  
Triazine Derivatives ◽  
Cleavage Reactions ◽  
Derivatives Of

The 5-arylazo-1-methyl-2-benzyl-2-imidazolin-4-ones (1 a-c) undergo ring cleavage with 1% aqueous sodium hydroxide solution affording α-arylhydrazono-phenacetyl-sarcosine amide (2). Prolonged heating of 1 and 2 with the same reagent yields the cyanamide (3). On the other hand, when 1 a-c were refluxed with acetic acid the triazinones (4) were obtained. The latter adds one mole of Grignards reagent to yield the 5-hydroxy-1,2,4-triazine derivatives (5).

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