Bifidobacterial enolase, a cell surface receptor for human plasminogen involved in the interaction with the host

The interaction with the host plasminogen/plasmin system represents a novel component in the molecular cross-talk between bifidobacteria and human host. Here, we demonstrated that the plasminogen-binding bifidobacterial species B. longum, B. bifidum, B. breve and B. lactis share the key glycolytic enzyme enolase as a surface receptor for human plasminogen. Enolase was visualized on the cell surface of the model strain B. lactis BI07. The His-tagged recombinant protein showed a high affinity for human plasminogen, with an equilibrium dissociation constant in the nanomolar range. By site-directed mutagenesis we demonstrated that the interaction between the B. lactis BI07 enolase and human plasminogen involves an internal plasminogen-binding site homologous to that of pneumococcal enolase. According to our data, the positively charged residues Lys-251 and Lys-255, as well as the negatively charged Glu-252, of the B. lactis BI07 enolase are crucial for plasminogen binding. Acting as a human plasminogen receptor, the bifidobacterial surface enolase is suggested to play an important role in the interaction process with the host.

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Faculty Opinions recommendation of A cell surface receptor mediates extracellular Ca(2+) sensing in guard cells.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1005494.201494 ◽

2004 ◽

Author(s):

Ramón Serrano

Keyword(s):

Cell Surface ◽

Guard Cells ◽

Cell Surface Receptor ◽

Surface Receptor ◽

A Cell

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Residues in domain III of the dengue virus envelope glycoprotein involved in cell-surface glycosaminoglycan binding

Journal of General Virology ◽

10.1099/vir.0.037317-0 ◽

2012 ◽

Vol 93 (1) ◽

pp. 72-82 ◽

Cited By ~ 61

Author(s):

Daniel Watterson ◽

Bostjan Kobe ◽

Paul R. Young

Keyword(s):

Cell Surface ◽

Dengue Virus ◽

Site Directed Mutagenesis ◽

Cell Surface Receptor ◽

Protein Fusion ◽

Virus Envelope ◽

Putative Receptor ◽

E Protein ◽

Surface Receptor ◽

Domain Iii

The dengue virus (DENV) envelope (E) protein mediates virus entry into cells via interaction with a range of cell-surface receptor molecules. Cell-surface glycosaminoglycans (GAGs) have been shown to play an early role in this interaction, and charged oligosaccharides such as heparin bind to the E protein. We have examined this interaction using site-directed mutagenesis of a recombinant form of the putative receptor-binding domain III of the DENV-2E protein expressed as an MBP (maltose-binding protein)-fusion protein. Using an ELISA-based GAG-binding assay, cell-based binding analysis and antiviral-activity assays, we have identified two critical residues, K291 and K295, that are involved in GAG interactions. These studies have also demonstrated differential binding between mosquito and human cells.

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P4-054: KLOTHO ENHANCES NEURONAL ACTIVITY THROUGH INTERACTION WITH A CELL-SURFACE RECEPTOR

Alzheimer s & Dementia ◽

10.1016/j.jalz.2018.06.2457 ◽

2006 ◽

Vol 14 (7S_Part_27) ◽

pp. P1453-P1454

Author(s):

Nicola J. Corbett ◽

Kate Fisher ◽

Helen A. Rowland ◽

Alys C. Jones ◽

Nigel M. Hooper

Keyword(s):

Cell Surface ◽

Neuronal Activity ◽

Cell Surface Receptor ◽

Surface Receptor ◽

A Cell

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STRA6, a Cell-Surface Receptor for Retinol-Binding Protein: The Plot Thickens

Cell Metabolism ◽

10.1016/j.cmet.2007.02.006 ◽

2007 ◽

Vol 5 (3) ◽

pp. 164-166 ◽

Cited By ~ 49

Author(s):

William S. Blaner

Keyword(s):

Cell Surface ◽

Binding Protein ◽

Retinol Binding Protein ◽

Cell Surface Receptor ◽

Surface Receptor ◽

A Cell

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230. Megalin, RAP and Nkx3.1 expression in the developing reproductive tract of a marsupial, the tammar wallaby

Reproduction Fertility and Development ◽

10.1071/srb08abs230 ◽

2008 ◽

Vol 20 (9) ◽

pp. 30

Author(s):

M. Gamat ◽

M. B. Renfree ◽

A. J. Pask ◽

G. Shaw

Keyword(s):

Cell Surface ◽

Reproductive Tract ◽

Tammar Wallaby ◽

Cell Surface Receptor ◽

Urogenital Sinus ◽

Receptor Associated Protein ◽

Wide Range ◽

Surface Receptor ◽

A Cell ◽

Strong Staining

Androgens induce the differentiation of the urogenital sinus (UGS) to form a prostate. An early marker of this response is upregulation of the transcription factor Nkx3.1 in the urogenital epithelium in the precursors of prostatic buds. In tammars, prostate differentiation begins ~3 weeks after birth and after the time the testis starts to secrete androgens, and 2 weeks after androgen stimulated Wolffian duct differentiation. The reason for this delay in prostate differentiation is unexplained. Androgen receptors are present in the UGS, and the potent androgen, androstanediol, induces prostatic development in females. Whilst androgens may diffuse into cells by across the cell membrane, there is increasing evidence that steroids are also internalised actively via the cell-surface transport molecule Megalin. We are exploring the possibility that the delay may be related to the establishment of a Megalin-mediated pathway. Megalin is a cell surface receptor expressed on epithelia and mediates the endocytosis of a wide range of ligands, including SHBG-bound sex steroids. Megalin action is regulated by Receptor Associated Protein (RAP), which acts as an antagonist to Megalin action. This study cloned partial sequences of Megalin, RAP and Nkx3.1 and examined their expression in the developing urogenital sinus of the tammar wallaby using RT–PCR. The cellular distribution of Megalin protein in the developing UGS was examined using immunohistochemistry. Megalin, RAP and Nkx3.1 in the tammar were all highly conserved with eutherian orthologueues. Megalin and Nkx3.1 transcripts were detected in the liver, kidney, ovary, testis and developing urogenital sinus of male and female tammars. In the developing UGS of the tammar, there was strong staining for Megalin protein in the urogenital epithelium with some diffuse staining in the surrounding mesenchyme. Together, these results suggest that Megalin could be a key gene in the mediation of androgen action in prostatic development in the tammar wallaby.

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