Cell Surface-associated Proteins of Gastrointestinal Strains of Lactobacilli

1992 ◽  
Vol 5 (3) ◽  
Author(s):  
P. Chagnaud ◽  
H. F. Jenkinson ◽  
G. W. Tannock
1984 ◽  
Vol 259 (9) ◽  
pp. 5915-5922 ◽  
Author(s):  
M Kurkinen ◽  
A Taylor ◽  
J I Garrels ◽  
B L Hogan

Yeast ◽  
2007 ◽  
Vol 24 (4) ◽  
pp. 253-258 ◽  
Author(s):  
Frans M. Klis ◽  
Marian de Jong ◽  
Stanley Brul ◽  
Piet W. J. de Groot

1993 ◽  
Vol 41 (9) ◽  
pp. 1367-1372 ◽  
Author(s):  
T J Cain ◽  
Y Liu ◽  
T Kobayashi ◽  
J M Robinson

Alkaline phosphatase (APase) belongs to a growing family of membrane-associated proteins tethered to the lipid bilayer via a glycosyl-phosphatidylinositol (GPI) anchor. Human neutrophils contain an intracellular pool of APase associated with a novel membrane-bound compartment. Stimulation of neutrophils with the chemotactic peptide formyl-Met-Leu-Phe (fMLP) leads to rapid up-regulation of essentially all of the APase to sites in continuity with the extracellular medium. Pre-treatment of neutrophils with cytochalasin B (cyto B) followed by fMLP likewise leads to expression of the enzyme on the cell surface and a dramatic alteration in cell morphology, but subsequent internalization of the plasmalemma is minimized. Pre-treatment with cyto B and fMLP has been used for isolation and purification of neutrophil APase. Specifically, neutrophils were treated with phosphatidylinositol-specific phospholipase C to release GPI-anchored proteins from the cell surface. APase was purified from supernatants of these preparations by electrophoresis in a non-denaturing gel system and subsequent electroelution. With this approach we rapidly purified neutrophil APase to homogeneity; this protein was then used for immunization. Immunoblotting, ELISA, and immunocytochemical localization were used to characterize the resulting antibodies.


1992 ◽  
Vol 5 (3) ◽  
pp. 121-131 ◽  
Author(s):  
P. Chagnaud ◽  
H. F. Jenkinson ◽  
G. W. Tannock

2009 ◽  
Vol 55 (8) ◽  
pp. 967-974 ◽  
Author(s):  
Abdellah Benachour ◽  
Thierry Morin ◽  
Laurent Hébert ◽  
Aurélie Budin-Verneuil ◽  
André Le Jeune ◽  
...  

Secreted and surface proteins of bacteria are key molecules that interface the cell with the environment. Some of them, corresponding to virulence factors, have already been described for Enterococcus faecalis , the predominant species involved in enterococcal nosocomial infections. In a global proteomic approach, the identification of the most abundant secreted and surface-associated proteins of E. faecalis JH2-2 strain was carried out. These proteins were separated by gel electrophoresis or directly subjected to in vivo trypsinolysis and then analyzed by liquid chromatography – electrospray ion trap tandem mass spectrometry. Putative functions were assigned by homology to the translated genomic database of E. faecalis. A total of 44 proteins were identified, eight secreted proteins from the supernatant culture and 38 cell surface proteins from two-dimensional gel electrophoresis and in vivo trypsinolysis among which two are common to the two groups. Their sequences analysis revealed that 35 of the 44 proteins harbour characteristic features (signal peptide or transmembrane domains) consistent with an extracellular localization. This study may be considered as an important step to encourage proteomic-based investigations of E. faecalis cell surface associated proteins that could lead to the discovery of virulence factors and to the development of new therapeutic tools.


1981 ◽  
Vol 1 (2) ◽  
pp. 128-135 ◽  
Author(s):  
P L Williamson ◽  
W A Massey ◽  
B M Phelps ◽  
R A Schlegel

Transformed murine hematopoietic cells of several lineages bound the fluorescent membrane probe merocyanine 540, whereas their normal counterparts did not. Similar selective binding was reproduced in artificial liposomes which bound this probe above their phase transition temperature, but not below it. The regions of the membrane to which merocyanine 540 binds along with the receptors for the lectin concanavalin A, but not the receptors for the lectin wheat germ agglutinin, were rearranged during the course of induced differentiation of erythroleukemia cells. Based on these findings, we propose a model of hematopoietic cell surface differentiation in which proteins such as concanavalin A receptors, which are destined for removal from the plasma membrane, are specifically associated with disordered, liquid-like lipid domains which can be visualized with merocyanine 540. For the specific case of erythroid differentiation, these domains and their associated proteins are collected at the region of the membrane where nuclear extrusion occurs and are eliminated from the reticulocyte plasma membrane by the enucleation event.


2004 ◽  
Vol 165 (5) ◽  
pp. 735-746 ◽  
Author(s):  
Anne K. Kenworthy ◽  
Benjamin J. Nichols ◽  
Catha L. Remmert ◽  
Glenn M. Hendrix ◽  
Mukesh Kumar ◽  
...  

Lipid rafts are conceptualized as membrane microdomains enriched in cholesterol and glycosphingolipid that serve as platforms for protein segregation and signaling. The properties of these domains in vivo are unclear. Here, we use fluorescence recovery after photobleaching to test if raft association affects a protein's ability to laterally diffuse large distances across the cell surface. The diffusion coefficients (D) of several types of putative raft and nonraft proteins were systematically measured under steady-state conditions and in response to raft perturbations. Raft proteins diffused freely over large distances (>4 μm), exhibiting Ds that varied 10-fold. This finding indicates that raft proteins do not undergo long-range diffusion as part of discrete, stable raft domains. Perturbations reported to affect lipid rafts in model membrane systems or by biochemical fractionation (cholesterol depletion, decreased temperature, and cholesterol loading) had similar effects on the diffusional mobility of raft and nonraft proteins. Thus, raft association is not the dominant factor in determining long-range protein mobility at the cell surface.


1991 ◽  
Vol 278 (1) ◽  
pp. 57-62 ◽  
Author(s):  
R Kannan ◽  
J Yuan ◽  
P S Low

In previous studies we have described a process whereby an erythrocyte in biochemical distress can initiate its own removal by macrophages of the reticuloendothelial system. This process involves the clustering of the integral membrane protein band 3 by denatured haemoglobin and the subsequent recognition of the exofacial poles of clustered band 3 and associated proteins by autologous antibodies. To determine whether this clearance pathway might mediate normal cell turnover, the fraction of normal erythrocytes containing the 0.5% densest cells, which are known to be destined for immediate removal, was isolated and characterized biochemically. This densest fraction was found to contain 6 times more membrane-bound globin (haemichromes) and 10 times more surface-bound autologous IgG than the other fractions containing cells of lower density. To determine whether the autologous IgG was physically associated with the haemichrome-stabilized membrane protein clusters, a procedure was developed for isolation and characterization of the microscopic aggregates. The isolated aggregates were found to contain a disulphide-cross-linked mixture of several membrane proteins, predominantly haemichromes, spectrin and band 3. Although the aggregates constituted only 0.09% of the total membrane protein, they still contained approximately 55% of the total cell-surface IgG. Since in control studies anti-(blood group A) antibodies, which are distributed randomly over the surface of type A cells, could not be recovered in the aggregate, we conclude that the autologous cell-surface IgGs were physically associated with the membrane protein clusters when they were co-isolated with them in our procedure. Thus the 640-fold enrichment of autologous IgG in the aggregates compared with regions of the membrane devoid of tightly clustered protein suggests that sites of integral protein clustering either are non-specifically sticky to IgG or are viewed as foreign or ‘non-self’ by the immune system and aggressively opsonized with IgG.


Sign in / Sign up

Export Citation Format

Share Document