Serine proteinase of Renibacterium salmoninarum digests a major autologous extracellular and cell-surface protein

1991 ◽  
Vol 37 (10) ◽  
pp. 758-763 ◽  
Author(s):  
D. D. Rockey ◽  
P. S. D Turaga ◽  
G. D. Wiens ◽  
B. A. Cook ◽  
S. L. Kaattari
Keyword(s):  
Cell Surface ◽  
Proteolytic Activity ◽  
Elevated Temperatures ◽  
Surface Protein ◽  
Major Constituent ◽  
Lauryl Sulfate ◽  
Cell Surface Protein ◽  
Renibacterium Salmoninarum ◽  
Native Form

Renibacterium salmoninarum is a pathogen of salmonid fish that produces large amounts of extracellular protein (ECP) during growth. A proteolytic activity present in ECP at elevated temperatures digested the majority of the proteins in ECP. This digestion was also associated with the loss of ECP immunosuppressive function. In vitro activity of the proteinase in ECP was temperature dependent: it was not detected in an 18-h digest at 4 and 17 °C but became readily apparent at 37 °C. Proteinase activity was detected at bacterial physiological temperatures (17 °C) in reactions incubated for several days. Under these conditions, digestion of partially purified p57, a major constituent of ECP and a major cell-surface protein, yielded a spectrum of breakdown products similar in molecular weight and antigenicity to those in ECP. This pattern of digestion suggests that most of the immunologically related constituents of ECP are p57 and its breakdown products. The proteolytic activity was sensitive to phenylmethylsulfonyl fluoride, methanol, and ethanol and to 10-min incubation at temperatures above 65 °C. Electrophoretic analysis of the proteinase on polyacrylamide gels containing proteinase substrates indicated the native form to be 100 kDa or greater. The enzyme was active against selected unrelated substrates only when coincubated with a denaturant (0.1% lauryl sulfate) and (or) a reducing agent (20 mM dithiothreitol). Key words: Renibacterium salmoninarum, proteinase, hemagglutinin, antigen F, bacterial kidney disease.

scholarly journals A high-molecular-mass cell-surface protein from Lactobacillus reuteri 1063 adheres to mucus components The GenBank accession number for the sequence reported in this paper is AF120104.

Microbiology ◽  
2002 ◽  
Vol 148 (2) ◽  
pp. 433-442 ◽  
Author(s):  
Stefan Roos ◽  
Hans Jonsson
Keyword(s):  
Cell Surface ◽  
Lactobacillus Reuteri ◽  
Surface Protein ◽  
Surface Proteins ◽  
Cell Surface Protein ◽  
Intestinal Mucus ◽  
A Cell ◽  
Molecular Masses ◽  
Ph Range

A gene from Lactobacillus reuteri 1063 encoding a cell-surface protein, designated Mub, that adheres to mucus components in vitro has been cloned and sequenced. The deduced amino acid sequence of Mub (358 kDa) shows the presence of 14 approximately 200 aa repeats and features typical for other cell-surface proteins of Gram-positive bacteria. Fusion proteins consisting of different repeats of Mub and the maltose-binding protein (MBP) were produced. These proteins adhered to pig mucus components, with molecular masses ranging from <0·1 to >2 MDa, to pig gastric mucin and to hen intestinal mucus. The binding of Mub to mucus components occurred in the pH range 3–7·4, with maximum binding at pH 4–5 and could be partly inhibited by the glycoprotein fetuin. Affinity-purified antibodies against recombinant Mub were used in immunofluorescence microscopy to demonstrate the presence of Mub on the cell surface of strain 1063. By using the antibodies in a Western blot analysis, Mub could also be detected in the growth medium. The results implicate Mub as a cell-surface protein that is involved in Lactobacillus interactions with mucin and in colonization of the digestive tract.

scholarly journals Function of Candida albicans Adhesin Hwp1 in Biofilm Formation

2006 ◽  
Vol 5 (10) ◽  
pp. 1604-1610 ◽  
Author(s):  
Clarissa J. Nobile ◽  
Jeniel E. Nett ◽  
David R. Andes ◽  
Aaron P. Mitchell
Keyword(s):  
Candida Albicans ◽  
Cell Surface ◽  
Biofilm Formation ◽  
Tight Binding ◽  
Surface Protein ◽  
Venous Catheter ◽  
Cell Surface Protein ◽  
Additional Support

ABSTRACT Hwp1 is a well-characterized Candida albicans cell surface protein, expressed only on hyphae, that mediates tight binding to oral epithelial cells. Prior studies indicate that HWP1 expression is dependent upon Bcr1, a key regulator of biofilm formation. Here we test the hypothesis that Hwp1 is required for biofilm formation. In an in vitro model, the hwp1/hwp1 mutant produces a thin biofilm that lacks much of the hyphal mass found in the hwp1/HWP1 reconstituted strain. In a biofilm cell retention assay, we find that the hwp1/hwp1 mutant is defective in retention of nonadherent bcr1/bcr1 mutant cells. In an in vivo rat venous catheter model, the hwp1/hwp1 mutant has a severe biofilm defect, yielding only yeast microcolonies in the catheter lumen. These properties of the hwp1/hwp1 mutant are consistent with its role as a hypha-specific adhesin and indicate that it is required for normal biofilm formation. Overexpression of HWP1 in a bcr1/bcr1 mutant background improves adherence in the in vivo catheter model. This finding provides additional support for the model that Hwp1 is critical for biofilm adhesion. Hwp1 is the first cell surface protein known to be required for C. albicans biofilm formation in vivo and is thus an excellent therapeutic target.

scholarly journals Identification and Characterization of a Novel Heme-Associated Cell Surface Protein Made by Streptococcus pyogenes

2002 ◽  
Vol 70 (8) ◽  
pp. 4494-4500 ◽  
Author(s):  
Benfang Lei ◽  
Laura M. Smoot ◽  
Heather M. Menning ◽  
Jovanka M. Voyich ◽  
Subbarao V. Kala ◽  
...  
Keyword(s):  
Recombinant Protein ◽  
Cell Surface ◽  
Surface Protein ◽  
Cell Surface Protein ◽  
Gene Encoding ◽  
Invasive Infections ◽  
Group A

ABSTRACT Analysis of the genome sequence of a serotype M1 group A Streptococcus (GAS) strain identified a gene encoding a previously undescribed putative cell surface protein. The gene was cloned from a serotype M1 strain, and the recombinant protein was overexpressed in Escherichia coli and purified to homogeneity. The purified protein was associated with heme in a 1:1 stoichiometry. This streptococcal heme-associated protein, designated Shp, was produced in vitro by GAS, located on the bacterial cell surface, and accessible to specific antibody raised against the purified recombinant protein. Mice inoculated subcutaneously with GAS and humans with invasive infections and pharyngitis caused by GAS seroconverted to Shp, indicating that Shp was produced in vivo. The blood of mice actively immunized with Shp had significantly higher bactericidal activity than the blood of unimmunized mice. The shp gene was cotranscribed with eight contiguous genes, including homologues of an ABC transporter involved in iron uptake in gram-negative bacteria. Our results indicate that Shp is a novel cell surface heme-associated protein.

The influence of an adhesive cell surface protein on chondrogenic expression in vitro

1979 ◽  
Vol 121 (2) ◽  
pp. 411-415 ◽  
Author(s):  
John P. Pennypacker ◽  
John R. Hassell ◽  
Kenneth M. Yamada ◽  
Robert M. Pratt
Keyword(s):  
Cell Surface ◽  
Surface Protein ◽  
Cell Surface Protein

scholarly journals Identification of tumorigenic cells and therapeutic targets in pancreatic neuroendocrine tumors

2016 ◽  
Vol 113 (16) ◽  
pp. 4464-4469 ◽  
Author(s):  
Geoffrey Wayne Krampitz ◽  
Benson M. George ◽  
Stephen B. Willingham ◽  
Jens-Peter Volkmer ◽  
Kipp Weiskopf ◽  
...  
Keyword(s):  
Cell Surface ◽  
Tumor Growth ◽  
Neuroendocrine Tumors ◽  
Surface Protein ◽  
Current Evidence ◽  
Cell Surface Protein ◽  
Pancreatic Neuroendocrine Tumors ◽  
Tumor Initiating Cells

Pancreatic neuroendocrine tumors (PanNETs) are a type of pancreatic cancer with limited therapeutic options. Consequently, most patients with advanced disease die from tumor progression. Current evidence indicates that a subset of cancer cells is responsible for tumor development, metastasis, and recurrence, and targeting these tumor-initiating cells is necessary to eradicate tumors. However, tumor-initiating cells and the biological processes that promote pathogenesis remain largely uncharacterized in PanNETs. Here we profile primary and metastatic tumors from an index patient and demonstrate that MET proto-oncogene activation is important for tumor growth in PanNET xenograft models. We identify a highly tumorigenic cell population within several independent surgically acquired PanNETs characterized by increased cell-surface protein CD90 expression and aldehyde dehydrogenase A1 (ALDHA1) activity, and provide in vitro and in vivo evidence for their stem-like properties. We performed proteomic profiling of 332 antigens in two cell lines and four primary tumors, and showed that CD47, a cell-surface protein that acts as a “don’t eat me” signal co-opted by cancers to evade innate immune surveillance, is ubiquitously expressed. Moreover, CD47 coexpresses with MET and is enriched in CD90hi cells. Furthermore, blocking CD47 signaling promotes engulfment of tumor cells by macrophages in vitro and inhibits xenograft tumor growth, prevents metastases, and prolongs survival in vivo.

DPP4 inhibitors as novel agents in improving survival in patients with prostate cancer: A SEER-Medicare study.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e16532-e16532
Author(s):  
Chintan Shah ◽  
Young-Rock Hong ◽  
Rohit Bishnoi ◽  
azka ali ◽  
William Paul Skelton ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cell Surface ◽  
Tumor Biology ◽  
Prospective Trial ◽  
Surface Protein ◽  
Cell Surface Protein ◽  
Cellular Mechanisms ◽  
Dpp4 Inhibitors ◽  
The Impact

e16532 Background: Dipeptidyl peptidase-4 (DPP4) is a cell surface protein expressed in variable amounts on different tissues and plays a vital role in tumor biology as well as regulation of the immune system. In-vitro studies have shown that the DPP4 biochemical activity is twice as high in prostate cancer cells compared to benign prostate tissues. Furthermore, blocking of DPP4 activity in-vitro was demonstrated to inhibit tumor angiogenesis and tumor invasiveness through a number of cellular mechanisms. Meanwhile, DPP4 expression is modest in normal as well as cancerous pancreatic cells. Methods: Using linked SEER and MEDICARE database, we identified patients with prostate cancer (PRC) or pancreatic cancer (PC) with coexisting type II diabetes mellitus. Furthermore, we analyzed the impact of DPP4 inhibition in the overall survival (OS) in these patients between 2001 and 2013. Analyses were performed using SAS, version 9.4. We excluded patients taking metformin. Results: We identified 7229 patients with PRC and 2401 patients with PC. OS was significantly better in PRC patients taking DPP4 inhibitors (262 patients) with HR 0.75 (95% CI: 0.59-0.97; P = 0.02) compared to those not on DPP4 inhibitors. Meanwhile, for patients with PC, OS was not significantly different between patients taking DPP4 inhibitors (177 patients) compared to those who were not (HR 1.03; 95% CI: 0.88-1.21; P = 0.7). Subgroup analyses of PRC patients demonstrated a trend toward a beneficial effect of DPP4 inhibitors, irrespective of stage (stage I, NR; stage II, HR 0.81; stage III, NR; stage IV, 0.76),use of chemotherapy (HR 0.83 with chemotherapy and HR 0.70 without chemotherapy) or hormonal use (ADT) (HR 0.87 with ADT and HR 0.71 without ADT), prostatectomy (HR 0.50 with prostatectomy and HR 0.77 with no prostatectomy) or radiation (HR 0.89 with radiation and HR 0.64 without radiation). Conclusions: This is the first population-based analysis showing the OS benefit of DPP4 inhibitors in PRC patients. On the other hand, OS was not improved in PC patients taking DPP4 inhibitors likely due to low levels of expression of DPP4 cell surface protein on pancreatic tissues. A prospective trial would help confirm our findings.

Immunogold and immunoblot studies on a cell surface protein found in primary mesenchyme cells and in the cortical secretory vesicles of the sea urchin egg

1987 ◽  
Vol 45 ◽  
pp. 832-833
Author(s):  
G.L. Decker ◽  
M.C. Valdizan
Keyword(s):  
Cell Surface ◽  
Sea Urchin ◽  
Surface Protein ◽  
Egg Cell ◽  
Secretory Vesicles ◽  
Cell Surface Protein ◽  
Surface Complexes ◽  
Mesenchyme Cells ◽  
Lowicryl K4m ◽  
Primary Mesenchyme Cells

A monoclonal antibody designated MAb 1223 has been used to show that primary mesenchyme cells of the sea urchin embryo express a 130-kDa cell surface protein that may be directly involved in Ca2+ uptake required for growth of skeletal spicules. Other studies from this laboratory have shown that the 1223 antigen, although in relatively low abundance, is also expressed on the cell surfaces of unfertilized eggs and on the majority of blastomeres formed prior to differentiation of the primary mesenchyme cells.We have studied the distribution of 1223 antigen in S. purpuratus eggs and embryos and in isolated egg cell surface complexes that contain the cortical secretory vesicles. Specimens were fixed in 1.0% paraformaldehyde and 1.0% glutaraldehyde and embedded in Lowicryl K4M as previously reported. Colloidal gold (8nm diameter) was prepared by the method of Mulpfordt.

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