Homology to region X from staphylococcal protein A is not unique to cell surface proteins

1987 ◽  
Vol 127 (3) ◽  
pp. 373-376 ◽  
Author(s):  
Gunnar von Heijne ◽  
Mathias Uhlén
Keyword(s):  
Cell Surface ◽  
Protein A ◽  
Surface Proteins ◽  
Staphylococcal Protein A ◽  
Cell Surface Proteins ◽  
Staphylococcal Protein

scholarly journals Regulation of agr-Dependent Virulence Genes in Staphylococcus aureus by RNAIII from Coagulase-Negative Staphylococci

1998 ◽  
Vol 180 (12) ◽  
pp. 3181-3186 ◽  
Author(s):  
Karin Tegmark ◽  
Eva Morfeldt ◽  
Staffan Arvidson
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Surface ◽  
Serine Protease ◽  
Protein A ◽  
Surface Proteins ◽  
Open Reading Frames ◽  
Alpha Toxin ◽  
Coagulase Negative Staphylococci ◽  
Cell Surface Proteins ◽  
Genes Encoding

ABSTRACT Many of the genes coding for extracellular toxins, enzymes, and cell surface proteins in Staphylococcus aureus are regulated by a 510-nucleotide (nt) RNA molecule, RNAIII. Transcription of genes encoding secreted toxins and enzymes, includinghla (alpha-toxin), saeB (enterotoxin B),tst (toxic shock syndrome toxin 1), and ssp(serine protease), is stimulated, while transcription of genes encoding cell surface proteins, like spa (protein A) andfnb (fibronectin binding proteins), is repressed. Besides being a regulator, RNAIII is also an mRNA coding for staphylococcal delta-lysin. We have identified RNAIII homologs in three different coagulase-negative staphylococci (CoNS), i.e., Staphylococcus epidermidis, Staphylococcus simulans, andStaphylococcus warneri. RNAIII from these CoNS turned out to be very similar to that of S. aureus and contained open reading frames encoding delta-lysin homologs. Though a number of big insertions and/or deletions have occurred, mainly in the 5′ half of the molecules, the sequences show a high degree of identity, especially in the first 50 and last 150 nt. The CoNS RNAIII had the ability to completely repress transcription of protein A in an RNAIII-deficientS. aureus mutant and the ability to stimulate transcription of the alpha-toxin and serine protease genes. However, the stimulatory effect was impaired compared to that of S. aureus RNAIII, suggesting that these regulatory functions are independent. By creating S. epidermidis-S. aureus RNAIII hybrids, we could also show that both the 5′ and 3′ halves of the RNAIII molecule are involved in the transcriptional regulation of alpha-toxin and serine protease mRNAs in S. aureus.

scholarly journals Endocytosis of liposomes bound to cell surface proteins measured by flow cytofluorometry

1983 ◽  
Vol 214 (1) ◽  
pp. 189-194 ◽  
Author(s):  
A Truneh ◽  
Z Mishal ◽  
J Barbet ◽  
P Machy ◽  
L D Leserman
Keyword(s):  
Flow Cytometry ◽  
Cell Surface ◽  
Membrane Surface ◽  
Protein A ◽  
Surface Proteins ◽  
Cellular Receptor ◽  
Cell Surface Proteins ◽  
Flow Cytofluorometry ◽  
High Concentrations ◽  
A New Technique

A new technique for the quantification of cellular receptor-mediated endocytosis has been developed based on the analysis by flow cytometry of ligand-bearing liposomes containing the fluorochrome carboxyfluorescein. Carboxyfluorescein encapsulated at high concentrations in protein A-bearing liposomes is self-quenched. Binding and internalization of such liposomes by cells via antibodies directed towards membrane surface determinants results in the release of the liposome-encapsulated carboxyfluorescein into the cytoplasm causing an increase in cell-associated fluorescence. This increase can be quantified on a flow cytofluorometer.

scholarly journals Staphylococcus aureusProtein A Mediates Interspecies Interactions at the Cell Surface ofPseudomonas aeruginosa

mBio ◽  
2016 ◽  
Vol 7 (3) ◽  
Author(s):  
Catherine R. Armbruster ◽  
Daniel J. Wolter ◽  
Meenu Mishra ◽  
Hillary S. Hayden ◽  
Matthew C. Radey ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Microbial Community ◽  
Cell Surface ◽  
Biofilm Formation ◽  
Protein A ◽  
Staphylococcal Protein A ◽  
Interspecies Interactions ◽  
Community Interactions ◽  
Staphylococcal Protein

ABSTRACTWhile considerable research has focused on the properties of individual bacteria, relatively little is known about how microbial interspecies interactions alter bacterial behaviors and pathogenesis.Staphylococcus aureusfrequently coinfects with other pathogens in a range of different infectious diseases. For example, coinfection byS. aureuswithPseudomonas aeruginosaoccurs commonly in people with cystic fibrosis and is associated with higher lung disease morbidity and mortality.S. aureussecretes numerous exoproducts that are known to interact with host tissues, influencing inflammatory responses. The abundantly secretedS. aureusstaphylococcal protein A (SpA) binds a range of human glycoproteins, immunoglobulins, and other molecules, with diverse effects on the host, including inhibition of phagocytosis ofS. aureuscells. However, the potential effects of SpA and otherS. aureusexoproducts on coinfecting bacteria have not been explored. Here, we show thatS. aureus-secreted products, including SpA, significantly alter two behaviors associated with persistent infection. We found that SpA inhibited biofilm formation by specificP. aeruginosaclinical isolates, and it also inhibited phagocytosis by neutrophils of all isolates tested. Our results indicate that these effects were mediated by binding to at least twoP. aeruginosacell surface structures—type IV pili and the exopolysaccharide Psl—that confer attachment to surfaces and to other bacterial cells. Thus, we found that the role of a well-studiedS. aureusexoproduct, SpA, extends well beyond interactions with the host immune system. Secreted SpA alters multiple persistence-associated behaviors of another common microbial community member, likely influencing cocolonization and coinfection with other microbes.IMPORTANCEBacteria rarely exist in isolation, whether on human tissues or in the environment, and they frequently coinfect with other microbes. However, relatively little is known about how microbial interspecies interactions alter bacterial behaviors and pathogenesis. We identified a novel interaction between two bacterial species that frequently infect together—Staphylococcus aureusandPseudomonas aeruginosa. We show that theS. aureus-secreted protein staphylococcal protein A (SpA), which is well-known for interacting with host targets, also binds to specificP. aeruginosacell surface molecules and alters two persistence-associatedP. aeruginosabehaviors: biofilm formation and uptake by host immune cells. BecauseS. aureusfrequently precedesP. aeruginosain chronic infections, these findings reveal how microbial community interactions can impact persistence and host interactions during coinfections.

scholarly journals Ligatin from embryonic chick neural retina.

1979 ◽  
Vol 80 (3) ◽  
pp. 642-650 ◽  
Author(s):  
E R Jakoi ◽  
R B Marchase
Keyword(s):  
Cell Surface ◽  
Plasma Membranes ◽  
Protein A ◽  
Neural Retina ◽  
Surface Proteins ◽  
Embryonic Chick ◽  
Cell Surface Proteins ◽  
Rat Ileum ◽  
Discrete Band

Ligatin, a filamentous protein previously found in suckling rat ileum, has been purified from plasma membranes of embryonic chick neural retina. The isolated plasma membranes are covered in part by 4.5-nm filaments that can be released from the membranes by treatment with Ca++. Subsequent dialysis against EGTA followed by sieve chromatography results in purification of the 10,000-dalton ligatin monomer. When labeled either with radioisotopes or with fluorescamine, the monomer is shown to electrophorese as a single discrete band in polyacrylamide gels. However, during standard fixing and staining procedures it diffuses from the gels and thus is not visualized. Ligatin's amino acid composition is distinguished by its high content of polar residues, especially Glx and Asx, and by the presence of phosphorylated serine. Upon re-addition of Ca++, purified ligatin monomers polymerize to form filaments 3 nm in Diam, identical to those formed by purified ileal ligatin. However, in both retina and ileum, the filaments observed on plasma membranes are greater than 3 nm in Diam. In ileum, this enlargement results from ligatin's function as a baseplate for the attachment of another protein, a beta-N-acetylhexosaminidase, to the cell surface. In retina, a corresponding difference in diameter between filaments seen in vivo and those formed from repolymerized ligatin alone and the co-solubilization of other proteins with ligatin suggest that ligatin may also function there as a baseplate for other cell surface proteins. The proteins associated with ligatin in retina differ morphologically from beta-N-acetylhexosaminidase and do not possess this enzymatic activity.

scholarly journals The YSIRK-G/S Motif of Staphylococcal Protein A and Its Role in Efficiency of Signal Peptide Processing

2003 ◽  
Vol 185 (9) ◽  
pp. 2910-2919 ◽  
Author(s):  
Taeok Bae ◽  
Olaf Schneewind
Keyword(s):  
Cell Wall ◽  
Signal Peptide ◽  
Protein A ◽  
Surface Proteins ◽  
Signal Peptides ◽  
Staphylococcal Protein A ◽  
Gram Positive ◽  
Peptide Processing ◽  
Staphylococcal Protein ◽  
Sorting Signal

ABSTRACT Many surface proteins of pathogenic gram-positive bacteria are linked to the cell wall envelope by a mechanism requiring a C-terminal sorting signal with an LPXTG motif. Surface proteins of Streptococcus pneumoniae harbor another motif, YSIRK-G/S, which is positioned within signal peptides. The signal peptides of some, but not all, of the 20 surface proteins of Staphylococcus aureus carry a YSIRK-G/S motif, whereas those of surface proteins of Listeria monocytogenes and Bacillus anthracis do not. To determine whether the YSIRK-G/S motif is required for the secretion or cell wall anchoring of surface proteins, we analyzed variants of staphylococcal protein A, an immunoglobulin binding protein with an LPXTG sorting signal. Deletion of the YSIR sequence or replacement of G or S significantly reduced the rate of signal peptide processing of protein A precursors. In contrast, cell wall anchoring or the functional display of protein A was not affected. The fusion of cell wall sorting signals to reporter proteins bearing N-terminal signal peptides with or without the YSIRK-G/S motif resulted in hybrid proteins that were anchored in a manner similar to that of wild-type protein A. The requirement of the YSIRK-G/S motif for efficient secretion implies the existence of a specialized mode of substrate recognition by the secretion pathway of gram-positive cocci. It seems, however, that this mechanism is not essential for surface protein anchoring to the cell wall envelope.

What do nanometer molecular trajectories tell us about heterogeneous cell surface domaines?

1995 ◽  
Vol 53 ◽  
pp. 786-787
Author(s):  
Watt W. Webb
Keyword(s):  
Cell Surface ◽  
Lipid Membranes ◽  
Surface Proteins ◽  
Protein Diffusion ◽  
Coated Pits ◽  
Cell Surface Proteins ◽  
Membrane Heterogeneity ◽  
Fluorescence Photobleaching Recovery ◽  
Photobleaching Recovery ◽  
Plasma Membrane Heterogeneity

Plasma membrane heterogeneity is implicit in the existence of specialized cell surface organelles which are necessary for cellular function; coated pits, post and pre-synaptic terminals, microvillae, caveolae, tight junctions, focal contacts and endothelial polarization are examples. The persistence of these discrete molecular aggregates depends on localized restraint of the constituent molecules within specific domaines in the cell surface by strong intermolecular bonds and/or anchorage to extended cytoskeleton. The observed plasticity of many of organelles and the dynamical modulation of domaines induced by cellular signaling evidence evanescent intermolecular interactions even in conspicuous aggregates. There is also strong evidence that universal restraints on the mobility of cell surface proteins persist virtually everywhere in cell surfaces, not only in the discrete organelles. Diffusion of cell surface proteins is slowed by several orders of magnitude relative to corresponding protein diffusion coefficients in isolated lipid membranes as has been determined by various ensemble average methods of measurement such as fluorescence photobleaching recovery(FPR).

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