Index Catalog // Scholar@UC

Apolipoprotein A-II-mediated Conformational Changes of Apolipoprotein A-I in Discoidal High Density Lipoproteins

Type:: Article
Description/Abstract:: Background: Role of apolipoprotein (apo) A-II on metabolism of high density lipoproteins (HDLs) is unknown. Results: Conformational changes of apoA-I, the major apolipoprotein of HDL, caused by apoA-II in discoidal HDL are confined to two regions of apoA-I. Conclusion: Interactions between the two major apolipoproteins in discoidal HDL are site specific. Significance: Functional implications of HDL complexes will significantly benefit from such structural information.
Creator/Author:: Gauthamadasa, Kekulawalage; Vaitinadin, Nataraja Sarma; Homan, Reyn; Macha, Stephen; Dresman, James L.; D. Silva, R. A. Gangani, and Greis, Kenneth D.
Submitter:: Kenneth Greis
Date Uploaded:: 03/01/2017
Date Modified:: 04/07/2017
Date Created:: 2012-03
License:: All rights reserved

Refined Structure of the Lipophosphoglycan of Leishmania donovani

Type:: Article
Description/Abstract:: The primary structure of the major surface glycoconjugate of Leishmania donovani parasites, a lipophosphoglycan, has been further characterized. The repeating PO4-6Galp beta 1-4Man disaccharide units, which are a salient feature of the molecule, are shown to terminate with one of several neutral structures, the most abundant of which is the branched trisaccharide Galp beta 1-4(Manp alpha 1-2)Man. The phosphosaccharide core of lipophosphoglycan, which links the disaccharide repeats to a lipid anchor, contains 2 phosphate residues. One of the core phosphates has previously been localized on O-6 of the galactosyl residue distal to the lipid anchor; the second phosphate is now shown to be on O-6 of the mannosyl residue distal to the anchor and to bear an alpha-linked glucopyranosyl residue. Also, the anomeric configuration of the unusual 3-substituted Galf residue in the phosphosaccharide core is established as beta. The complete structure of the core is thus PO4-6Galp alpha 1-6Galp alpha 1-3Galf beta 1-3[Glcp alpha 1-PO4-6]Manp alpha 1-3Manp alpha 1-4GlcN alpha 1-. This further clarification of the structure of lipophosphoglycan may prove beneficial in determining the structure-function relationships of this highly unusual glycoconjugate.
Creator/Author:: Ferguson, Michael A. J.; Turco, Salvatore J.; Thomas, Jerry R.; Gorin, Philip A. J.; Homans, Steven W.; McConville, Malcom J.; Greis, Kenneth D., and Thomas-Oates, Jane E.
Submitter:: Kenneth Greis
Date Uploaded:: 03/01/2017
Date Modified:: 04/07/2017
Date Created:: 1992-05
License:: All rights reserved

Purification and Characterization an Extracellular Phosphoglycan from Leishmania donovani

Type:: Article
Description/Abstract:: An extracellular phosphoglycan (exPG), present in the culturem edium of the promastigote form L oefi shmania donovani, was purified and structurally characterized. The purification scheme included ethanol precipitation of the culture medium, anion exchange chromatography, hydrophobic chromatography on phenyl-Sepharose, and preparative polyacrylamgeild e electrophoresis. Structural analysis by ‘H-’H NMR, methylation linkage analysis, and glycosidase digestion revealed that the exPG consisted of thfoel lowing structure: (CAP)+[P04-6Galp@1-4Manpal]lo-11-POr6GalpB1-4Man. The capw as found to be ones eovf eral small, neutral oligosaccharides, the most abundant of which was the trisaccharide Galp@l-4(Manpal-2)Man. The results indicated structural analogy to the cellular-derived lipophosphoglycan (LPG) from L. donovani. The important exceptions are a lacko f the lipid anchor, the entire phosphosaccharide core, and several of the repeating disaccharide units. Although the function of exPGis presently unknowni,t may play a protective role for the promastigote in the insect vector or during infection of a mammalian host
Creator/Author:: Turco, Salvatore J.; Thomas, Jerry R.; Homans, Steven W.; Ferguson, Michael A.; McConville, Malcolm J., and Greis, Kenneth D.
Submitter:: Kenneth Greis
Date Uploaded:: 03/01/2017
Date Modified:: 04/07/2017
Date Created:: 1992-04
License:: All rights reserved

An effective skeletal muscle prefractionation method to remove abundant structural proteins for optimized two-dimensional gel electrophoresis

$Article thumbnail: An effective skeletal muscle prefractionation method to remove abundant structural proteins for optimized two-dimensional gel electrophoresis$

Type:: Article
Description/Abstract:: Proteomic analysis of biological samples in disease models or therapeutic intervention studies requires the ability to detect and identify biologically relevant proteins present in relatively low concentrations. The detection and analysis of these low-level proteins is hindered by the presence of a few proteins that are expressed in relatively high concentrations. In the case of muscle tissue, highly abundant structural proteins, such as actin, myosin, and tropomyosin, compromise the detection and analysis of more biologically relevant proteins. We have developed a practical protocol which exploits high-pH extraction to reduce or remove abundant structural proteins from skeletal muscle crude membrane preparations in a manner suitable for two dimensional gel electrophoresis. An initial whole-cell muscle lysate is generated by homogenization of powdered tissue in Tris-base. This lysate is subsequently partitioned into a supernatant and pellet containing the majority of structural proteins. Treatment of the pellet with high-pH conditions effectively releases structural proteins from membrane compartments which are then removed through ultracentrifugation. Mass spectrometric identification shows that the majority of protein spots reduced or removed by high-pH treatment were contractile proteins or contractile-related proteins. Removal of these proteins enabled successful detection and identification of minor proteins. Structural protein removal also results in significant improvement of gel quality and the ability to load higher amounts of total protein for the detection of lower abundant protein classes.
Creator/Author:: Wang, Feng; Jarrold, Bradley; Burt, Thomas; DeMuth, Jeffrey, and Greis, Kenneth D.
Submitter:: Kenneth Greis
Date Uploaded:: 03/01/2017
Date Modified:: 04/07/2017
Date Created:: 2005-06
License:: All rights reserved

Lamprometra palmata - 1

Type:: Image
Description/Abstract:: Lamprometra palmata, at top, with arms of Capillaster sp cf C. multiradiatus below it, at night
Creator/Author:: Meyer, David L.
Submitter:: David L. Meyer
Date Uploaded:: 02/21/2017
Date Modified:: 02/21/2017
Date Created:: 2017-02-21
License:: Attribution-NonCommercial 4.0 International

Phanogenia gracilis - 3

Type:: Image
Description/Abstract:: Phanogenia gracilis, showing calyx and proximal arms; stellate centrodorsal is non-cirrate
Creator/Author:: Meyer, David L.
Submitter:: David L. Meyer
Date Uploaded:: 02/21/2017
Date Modified:: 02/21/2017
Date Created:: 2017-02-21
License:: Attribution-NonCommercial 4.0 International

Phanogenia gracilis - 2

Type:: Image
Description/Abstract:: Phanogenia gracilis, at upper left, with Stephanometra sp. at center
Creator/Author:: Meyer, David L.
Submitter:: David L. Meyer
Date Uploaded:: 02/21/2017
Date Modified:: 02/21/2017
Date Created:: 2017-02-21
License:: Attribution-NonCommercial 4.0 International