Binding of adenosine derivatives to carrier proteins may reduce their antiplatelet activity

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.

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Increased Serum Concentration of Free L-Triiodothyronine in Patients Treated with L-Thyroxine

Nuklearmedizin ◽

10.1055/s-0038-1624142 ◽

1983 ◽

Vol 22 (05) ◽

pp. 251-254

Author(s):

R. Schmitz ◽

H. Bongers ◽

A. Löw ◽

J. Mahlstedt ◽

K. Joseph ◽

...

Keyword(s):

Oral Dose ◽

Serum Concentration ◽

Normal Level ◽

Binding Sites ◽

Carrier Proteins ◽

Normal Range ◽

Free T4 ◽

Normal Concentration ◽

Free T3 ◽

High Doses

This study demonstrates that in spite of measured normal concentrations of carrier proteins one cannot deduce in all cases a normal fT3 from a normal level of TT3 when 1-thyroxine given for diagnostic or therapeutic purposes is present in excess. The displacement of 1-triiodothyronine from its binding sites is shown in 35 patients with non-toxic goitre who received an oral dose of 200 μg 1-thyroxine/die for two weeks. Apart from a significant increase of TT4 (from 7.85 to 14.21 μg/dl ≙ + 81 %) and of fT4 (from 1.58 to 3.7 ng/dl ≙ + 134%) there is only a slight increase in TT3 from 148 to 158 ng/dl (≙ + 10%) after 14 days of treatment. By contrast fT3 rises clearly from 4.97 to 8.07 pg/ml ≙ + 63% (normal range: 2.8-5.6 pg/ml). Compared with the increase of TT3 (+ 10%) the free T3 rises by a factor of 6.3 (63 %/10%). On account of higher affinity of 1-thyroxine to binding proteins the free T4 is influenced to a lesser degree. Compared with the increase of TT4 (+ 81 %) free T4 rises by a factor of 1.6 (134%/81 %). It is supposed that the serum concentration of free T3 can be increased despite a normal concentration of TT3 when 1-thyroxine is present in excess. Therefore, for laboratory work fT3 should be assigned a higher validity than TT3 when patients are treated with comparatively high doses of 1-thyroxine.

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Faculty Opinions recommendation of Co-opting sulphur-carrier proteins from primary metabolic pathways for 2-thiosugar biosynthesis.

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

10.3410/f.718382446.793528208 ◽

2017 ◽

Author(s):

Gong-Li Tang

Keyword(s):

Metabolic Pathways ◽

Carrier Proteins

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Expression of solute carrier proteins SLC35E1 and SLC35E2B in skin lesions of patients with Mycobacterium infection

Chinese Journal of Dermatology ◽

10.35541/cjd.20200429 ◽

2021 ◽

Keyword(s):

Skin Lesions ◽

Carrier Proteins ◽

Mycobacterium Infection ◽

Solute Carrier

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Structure, function and dynamics in acyl carrier proteins

PLoS ONE ◽

10.1371/journal.pone.0219435 ◽

2019 ◽

Vol 14 (7) ◽

pp. e0219435 ◽

Cited By ~ 3

Author(s):

Rohit Farmer ◽

Christopher Morton Thomas ◽

Peter James Winn

Keyword(s):

Structure Function ◽

Carrier Proteins ◽

Acyl Carrier Proteins

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Functional heterogeneity of ubiquitin carrier proteins.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)89632-6 ◽

1985 ◽

Vol 260 (3) ◽

pp. 1573-1581 ◽

Cited By ~ 16

Author(s):

C M Pickart ◽

I A Rose

Keyword(s):

Carrier Proteins ◽

Functional Heterogeneity

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The identification of novel immunogenic antigens as potential Shigella vaccine components

Genome Medicine ◽

10.1186/s13073-020-00824-4 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Ruklanthi de Alwis ◽

Li Liang ◽

Omid Taghavian ◽

Emma Werner ◽

Hao Chung The ◽

...

Keyword(s):

Core Genome ◽

Genomic Analysis ◽

Carrier Proteins ◽

Vaccine Candidates ◽

Vaccine Antigens ◽

Bactericidal Antibody ◽

In Vivo Testing ◽

Species Specific ◽

Selection Of

Abstract Background Shigella is a major diarrheal pathogen for which there is presently no vaccine. Whole genome sequencing provides the ability to predict and derive novel antigens for use as vaccines. Here, we aimed to identify novel immunogenic Shigella antigens that could serve as Shigella vaccine candidates, either alone, or when conjugated to Shigella O-antigen. Methods Using a reverse vaccinology approach, where genomic analysis informed the Shigella immunome via an antigen microarray, we aimed to identify novel immunogenic Shigella antigens. A core genome analysis of Shigella species, pathogenic and non-pathogenic Escherichia coli, led to the selection of 234 predicted immunogenic Shigella antigens. These antigens were expressed and probed with acute and convalescent serum from microbiologically confirmed Shigella infections. Results Several Shigella antigens displayed IgG and IgA seroconversion, with no difference in sero-reactivity across by sex or age. IgG sero-reactivity to key Shigella antigens was observed at birth, indicating transplacental antibody transfer. Six antigens (FepA, EmrK, FhuA, MdtA, NlpB, and CjrA) were identified in in vivo testing as capable of producing binding IgG and complement-mediated bactericidal antibody. Conclusions These findings provide six novel immunogenic Shigella proteins that could serve as candidate vaccine antigens, species-specific carrier proteins, or targeted adjuvants.

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Random and combinatorial mutagenesis for improved total production of secretory target protein in Escherichia coli

Scientific Reports ◽

10.1038/s41598-021-84859-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

David Gonzalez-Perez ◽

James Ratcliffe ◽

Shu Khan Tan ◽

Mary Chen May Wong ◽

Yi Pei Yee ◽

...

Keyword(s):

Escherichia Coli ◽

Protein Secretion ◽

Protein Production ◽

Secretory Protein ◽

Target Protein ◽

Carrier Protein ◽

Signal Peptides ◽

Carrier Proteins ◽

E Coli ◽

Combinatorial Mutagenesis

AbstractSignal peptides and secretory carrier proteins are commonly used to secrete heterologous recombinant protein in Gram-negative bacteria. The Escherichia coli osmotically-inducible protein Y (OsmY) is a carrier protein that secretes a target protein extracellularly, and we have previously applied it in the Bacterial Extracellular Protein Secretion System (BENNY) to accelerate directed evolution. In this study, we reported the first application of random and combinatorial mutagenesis on a carrier protein to enhance total secretory target protein production. After one round of random mutagenesis followed by combining the mutations found, OsmY(M3) (L6P, V43A, S154R, V191E) was identified as the best carrier protein. OsmY(M3) produced 3.1 ± 0.3 fold and 2.9 ± 0.8 fold more secretory Tfu0937 β-glucosidase than its wildtype counterpart in E. coli strains BL21(DE3) and C41(DE3), respectively. OsmY(M3) also produced more secretory Tfu0937 at different cultivation temperatures (37 °C, 30 °C and 25 °C) compared to the wildtype. Subcellular fractionation of the expressed protein confirmed the essential role of OsmY in protein secretion. Up to 80.8 ± 12.2% of total soluble protein was secreted after 15 h of cultivation. When fused to a red fluorescent protein or a lipase from Bacillus subtillis, OsmY(M3) also produced more secretory protein compared to the wildtype. In this study, OsmY(M3) variant improved the extracellular production of three proteins originating from diverse organisms and with diverse properties, clearly demonstrating its wide-ranging applications. The use of random and combinatorial mutagenesis on the carrier protein demonstrated in this work can also be further extended to evolve other signal peptides or carrier proteins for secretory protein production in E. coli.

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Endogenous digoxin-like immunoreactive factors: impact on digoxin measurements and potential physiological implications.

Clinical Chemistry ◽

10.1093/clinchem/31.9.1525 ◽

1985 ◽

Vol 31 (9) ◽

pp. 1525-1532 ◽

Cited By ~ 75

Author(s):

R Valdes

Keyword(s):

Renal Failure ◽

Liver Failure ◽

Pregnant Women ◽

Serum Proteins ◽

Newborn Infants ◽

Normal Subjects ◽

Carrier Proteins ◽

Third Trimester ◽

Weakly Bound ◽

Urine And Serum

Abstract Various laboratories have reported endogenous digoxin-like immunoreactive factor(s) (DLIF) in blood from patients in renal failure or liver failure, from newborn infants, and from third-trimester pregnant women. Similar immunoreactivity has been detected in amniotic fluid, in cord blood, and in urine and serum from normal subjects. The factor(s) giving rise to this immunoreactivity cross react with antibodies used in many currently available immunoassays for digoxin, sometimes causing apparent digoxin concentrations exceeding the therapeutic range obtained for exogenous digoxin, with consequent errors in measurement and in subsequent clinical interpretation of digoxin results. Here, I summarize findings in our laboratory and those of others. DLIF evidently exist in three states in serum: tightly protein-bound, weakly protein-bound, and unbound (free). In normal subjects, greater than 90% of the total DLIF in serum is tightly but reversibly bound to serum proteins and is not readily detectable by direct measurement of digoxin in serum with conventional immunoassays. However, there seems to be a redistribution of the more weakly bound and unbound components in patients with renal failure, pregnant women, and newborns. The increased values detected in these groups are ascribable to increased amounts of weakly bound and unbound DLIF rather than to increased total DLIF. Carrier proteins may play a prominent role in the transport of these factors in blood. I discuss the potential physiological and pharmacological implications of detecting endogenous immunoreactive factors that cross react with antibodies to drugs.

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