Zinc- and copper-binding proteins in the plasma of winter flounder (Pseudopleuronectes americanus)

1980 ◽  
Vol 58 (4) ◽  
pp. 609-613 ◽  
Author(s):  
P. E. Fletcher ◽  
G. L. Fletcher
Keyword(s):  
Molecular Weight ◽  
Binding Proteins ◽  
Binding Protein ◽  
Gel Filtration ◽  
Protein S ◽  
Egg Yolk ◽  
Winter Flounder ◽  
Zinc Binding ◽  
Copper Binding ◽  
Copper Binding Proteins

Zinc- and copper-binding proteins were isolated from the plasma of winter flounder using gel filtration chromatography. A single copper-binding protein fraction of molecular weight 170 000 was isolated from the plasma of both sexes.In male and female flounder over 95% of the plasma zinc was associated with a zinc-binding protein(s) with a molecular weight of 76 000. In male flounder the remaining zinc appeared to be bound to a protein(s) of molecular weight 186 000. In female flounder the remaining 5% of the zinc was associated with two zinc-binding fractions with apparent molecular weights of 186 000 and 340 000 – 370 000.Extracts of plasma vitellogenin and egg yolk proteins revealed significant quantities of zinc and copper. It is hypothesized that the female specific zinc-binding protein (340 000 – 370 000) was vitellogenin.

High molecular weight zinc- and copper-binding proteins in the liver of the rat; Effect of centrifugation

1987 ◽  
Vol 135 (2) ◽  
pp. 129-132
Author(s):  
J.B. Dielhof, ◽  
J.G. Van Der Enden, ◽  
TH.M.W. Stolk ◽  
C.J.A. Van Den Hamer,
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Binding Proteins ◽  
Copper Binding ◽  
Copper Binding Proteins

Isolation of copper-binding proteins from activated sludge culture

2001 ◽  
Vol 44 (2-3) ◽  
pp. 453-459 ◽  
Author(s):  
K. Fukushi ◽  
S. Kato ◽  
T. Antsuki ◽  
T. Omura
Keyword(s):  
Molecular Weight ◽  
Activated Sludge ◽  
Metal Uptake ◽  
Binding Proteins ◽  
Growth Media ◽  
Copper Binding ◽  
Molecular Weights ◽  
Binding Capability ◽  
Copper Binding Proteins

Six copper-binding microbial proteins were isolated from activated sludge cultures grown on media containing copper at various concentrations. Molecular weights among isolated proteins were ranged from 1.3k to 174k dalton. Isolated proteins were compared for their copper binding capabilities. Proteins isolated from cultures grown in the presence of copper in the growth media exhibited higher copper binding capabilities than those isolated from the culture grown in the absence of copper. The highest metal uptake of 61.23 (mol copper/mol protein) was observed by a protein isolated from a culture grown with copper at a concentration of 0.25 mM. This isolated protein (CBP2) had a molecular weight of 24k dalton. Other protein exhibited copper binding capability of 4.8-32.5 (mol copper/mol protein).

scholarly journals Physiological zinc-binding proteins of medium molecular weight in the rat gut

1986 ◽  
Vol 55 (2) ◽  
pp. 369-377 ◽  
Author(s):  
Malcolm J. Jackson ◽  
Daphne Holt ◽  
Michael Webb ◽  
Nicholas D. Carter
Keyword(s):  
Molecular Weight ◽  
Binding Proteins ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Exchange Chromatography ◽  
Zinc Binding ◽  
Intragastric Administration ◽  
Ileal Segment ◽  
Mucosal Cells ◽  
Rat Gut

1. Gel filtration on Sephadex G 75 was used to separate the medium-molecular-weight zinc-binding proteins from the soluble fractions from the duodenal and jejuno-ileal segments of the rat gut at 30 min after the intragastric administration of a tracer dose of 65Zn. These proteins were resolved by ion-exchange chromatography on DEAE cellulose.2. In both the duodenum and jejuno-ileal segment an appreciable fraction of the total soluble Zn was bound in a protein fraction that resembled metallothionein [MT] in its behaviour on gel filtration. These fractions, however, were not homogeneous, but contained several medium-molecular-weight Zn-binding proteins. In the duodenum, but not in the jejuno-ileal segment, two ofthese proteins appeared to be the isometallothioneins, ZnMT-I and ZnMT-11.3. These results suggest a possible role for MT in the binding of newly-absorbed Zn in the duodenal mucosal cells. They also show that gel filtration alone is insufficient for the identification of MT in the intestine.

scholarly journals Relationship between biotin-binding proteins from chicken plasma and egg yolk

1978 ◽  
Vol 175 (2) ◽  
pp. 629-633 ◽  
Author(s):  
R D Mandella ◽  
H W Meslar ◽  
H B White
Keyword(s):  
Binding Proteins ◽  
Elevated Temperatures ◽  
Binding Protein ◽  
Gel Filtration ◽  
Egg Yolk ◽  
Egg White ◽  
Similar Molecular Weight ◽  
Precipitin Line ◽  
Ion Exchange Column ◽  
Biotin Binding

The plasma of laying hens contains a specific biotin-binding protein that appears to be identical with an egg-yolk biotin-binding protein. Both proteins are saturated with biotin and require elevated temperatures to effect the exchange of [14C]biotin for the protein-bound vitamin. The heat-exchange curve in each case is the same and differs sharply from that of avidin, the egg-white biotin-binding protein. On Sephadex G-100 gel filtration, plasma and yolk biotin-binding proteins were each eluted slightly ahead of avidin (mol.wt. 68,000), suggesting that they are of similar molecular weight. Plasma and yolk biotin-binding proteins required the same ionic strength to be eluted from a phosphocellulose ion-exchange column. Both the plasma and yolk biotin-binding proteins had a pI of 5; avidin has a pI of 10. Plasma biotin-binding protein cross-reacted with antiserum to yolk biotin-binding protein and showed a precipitin line of identity with purified yolk biotin-binding protein. It is suggested that biotin-binding plays an important role in mediating the transport of the vitamin from the bloodstream to the developing oocyte.

scholarly journals Studies on the appearance of a hepatic copper-binding protein in normal and zinc-deficient rats

1976 ◽  
Vol 36 (1) ◽  
pp. 101-112 ◽  
Author(s):  
I. Bremner ◽  
N. T. Davies
Keyword(s):  
Molecular Weight ◽  
Metal Binding ◽  
Binding Protein ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Low Molecular Weight ◽  
Copper Binding ◽  
Hepatic Copper ◽  
Copper Binding Protein ◽  
Molecular Weight Form

1. A study has been made by gel-filtration techniques of the soluble copper- and zinc-binding proteins in rat liver after both intraperitoneal injection of Cu and dietary Cu supplementation.2. Liver Cu and Zn concentrations increased after injection of Cu, both metals accumulating in the cytosol, mainly in a fraction with an apparent molecular weight of (about 12 000)3. When Zn-deficient rats were injected with Cu, there was little change in liver Zn concentration and the occurrence of Cu in the low-molecular-weight form (about 12 000) was more transient. At most periods after injection, Cu accumulated mainly in a fraction with a molecular weight greater than 65 000.4. When the rats were Cu-loaded by dietary supplementation, virtually no Cu or Zn was found in the low-molecular-weight form in Zn-deficient rats, although they were found in the Zn-supplemented animals.5. The results suggest that Zn is essential for the accumulation of Cu in this form, but not for Cu to stimulate production of the metal-binding protein by a process requiring active protein synthesis.

scholarly journals Apoceruloplasmin: Abundance, Detection, Formation, and Metabolism

Biomedicines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 233
Author(s):  
Maria C. Linder
Keyword(s):  
Blood Plasma ◽  
Binding Proteins ◽  
Binding Protein ◽  
Free Form ◽  
Copper Binding ◽  
Disease States ◽  
Copper Binding Protein ◽  
Copper Binding Proteins

Ceruloplasmin, the main copper-binding protein in blood and some other fluids, is well known for its copper-dependent enzymatic functions and as a source of copper for cells. What is generally unknown or ignored is that, at least in the case of blood plasma and serum, about half of ceruloplasmin is in the apo (copper-free) form. This has led to some misconceptions about the amounts and variations of other copper-binding proteins and so-called “free copper” in the blood that might be indicators of disease states. What is known about the levels, sources, and metabolism of apo versus holo ceruloplasmin and the problems associated with measurements of the two forms is reviewed here.

scholarly journals Hepatic copper–and zinc-binding proteins in ruminants

1974 ◽  
Vol 32 (2) ◽  
pp. 293-300 ◽  
Author(s):  
I Bremner ◽  
R. B Marshall
Keyword(s):  
Molecular Weight ◽  
Binding Proteins ◽  
Gel Filtration ◽  
Weight Fraction ◽  
Zinc Binding ◽  
Molecular Weights ◽  
Hepatic Copper ◽  
Copper And Zinc ◽  
Zn Status ◽  
Cu And Zn

1. A study has been made by gel-filtration techniques of the soluble copper- and zinc-binding proteins in livers from calves and sheep of widely differing Cu and Zn status.2. Cu and Zn generally occurred together in three main fractions, with approximate molecular weights of > 75000, 35000 and 12000, and Zn also in one other fraction with molecular weight about 65000. The distribution of the metals between these fractions was variable and dependent on both the Cu and Zn status of the animals.3. Zn was usually absent from the low-molecular-weight fraction in Zn-deficient or high-Cu livers, with Cu also being absent in the former instance.4. The fraction with molecular weight of 35000 was tentatively identified as hepatocuprein. It generally accounted for only 4% of the total hepatic Cu except in Cu-deficient livers.5. The possible relationship of these findings to the mutual antagonism between Cu and Zn is discussed.

Rap1b Association with the Platelet Cytoskeleton Occurs in the Absence of Glycoproteins IIb/IIIa

1998 ◽  
Vol 79 (04) ◽  
pp. 832-836 ◽  
Author(s):  
Thomas Fischer ◽  
Christina Duffy ◽  
Gilbert White
Keyword(s):  
Molecular Weight ◽  
Divalent Cation ◽  
Binding Proteins ◽  
Binding Protein ◽  
Platelet Membrane ◽  
Low Molecular Weight ◽  
Membrane Glycoproteins ◽  
Gtp Binding Protein ◽  
Gtp Binding Proteins ◽  
Gtp Binding

SummaryPlatelet membrane glycoproteins (GP) IIb/IIIa and rap1b, a 21 kDa GTP binding protein, associate with the triton-insoluble, activation-dependent platelet cytoskeleton with similar rates and divalent cation requirement. To examine the possibility that GPIIb/IIIa was required for rap1b association with the cytoskeleton, experiments were performed to determine if the two proteins were linked under various conditions. Chromatography of lysates from resting platelets on Sephacryl S-300 showed that GPIIb/IIIa and rap1b were well separated and distinct proteins. Immunoprecipitation of GPIIb/IIIa from lysates of resting platelets did not produce rap1b or other low molecular weight GTP binding proteins and immunoprecipitation of rap1b from lysates of resting platelets did not produce GPIIb/IIIa. Finally, rap1b was associated with the activation-dependent cytoskeleton of platelets from a patient with Glanzmann’s thrombasthenia who lacks surface expressed glycoproteins IIb and IIIa. Based on these findings, we conclude that no association between GPIIb/IIIa and rap1b is found in resting platelets and that rap1b association with the activation-dependent cytoskeleton is at least partly independent of GPIIb/IIIa.

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