Separation of Two Dissolved Reactive Phosphorus Fractions in Lakewater

1978 ◽  
Vol 35 (12) ◽  
pp. 1636-1639 ◽  
Author(s):  
Malcolm T. Downes ◽  
Hans W. Paerl
Keyword(s):  
Molecular Weight ◽  
Key Words ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Molybdenum Blue ◽  
Dissolved Reactive Phosphorus ◽  
P Fraction ◽  
Analytical Reagents ◽  
Reactive Phosphorus ◽  
Hydrolysis Of

A method for the separation of two dissolved reactive phosphorus (DRP) fractions in unconcentrated lakewater is described. A reactive high molecular weight phosphorus (RHMW-P) fraction has been found in all waters studied and a second fraction, corresponding to orthophosphate (PO4-P) is frequently detected. The hydrolysis of RHMW-P to PO4-P by acid in the analytical reagents is shown to be the most likely reason for its determination as DRP. Key words: freshwater analysis, reactive phosphorus, orthophosphate, molybdenum blue method, gel filtration

Biological Availability of Low Versus High Molecular Weight Reactive Phosphorus

1978 ◽  
Vol 35 (12) ◽  
pp. 1639-1643 ◽  
Author(s):  
Hans W. Paerl ◽  
Malcolm T. Downes
Keyword(s):  
Molecular Weight ◽  
New Zealand ◽  
Key Words ◽  
High Molecular Weight ◽  
Growth Response ◽  
Growth Yields ◽  
Good Growth ◽  
Biological Availability ◽  
Culture Filtrates ◽  
Reactive Phosphorus

When equivalent concentrations of reactive high molecular weight phosphorus (RHMW-P > 5000) and free orthophosphate (PO4-P) from Lake Tutaeinanga, New Zealand, were added to P-starved Chlorella cultures, free PO4 showed a faster growth response within 48 h than RHMW-P. Algal preference for PO4 over RHMW-P could also be shown by (32P)PO4 turnover experiments. After 96 h both fractions showed good growth yields. Analyses on culture filtrates indicated that all forms of reactive P had been removed. This demonstrates that RHMW-P, which reacts with "reactive P" reagents, can eventually be utilized. Key words: reactive phosphorus, orthophosphate, algae, Chlorella, growth, bioassay

"Colloidal" Phosphorus Errors in Gel Chromatography

1983 ◽  
Vol 40 (10) ◽  
pp. 1614-1621 ◽  
Author(s):  
B. Kent Burnison
Keyword(s):  
Molecular Weight ◽  
Acid Hydrolysis ◽  
High Molecular Weight ◽  
Gel Chromatography ◽  
Chemical Analyses ◽  
Molybdophosphoric Acid ◽  
Molybdenum Blue ◽  
Soluble Reactive Phosphate ◽  
Colloidal Phosphorus ◽  
Hydrolysis Of

Gel chromatography has been used for the separation of 32PO4 and a high molecular weight "colloidal" 32P-labeled fraction from 32PO4-labeled lakewater. When the labeled filtrate is treated with reagents required for the molybdenum blue method for orthophosphate analysis, only a small fraction of the "colloidal" peak is hydrolyzed to orthophosphate. As the reduced molybdophosphoric acid is strongly adsorbed to the dextran gel, quantitative elution of 32PO4 can be achieved with 0.05 mol∙L−1 NaOH and 0.3% NaCl. In hardwater lakes, care must be taken to eliminate the possibility of orthophosphate precipitation at higher pH. In these lakes, it is unlikely that the discrepancy between 32PO4 bioassays and chemical analyses can be solely attributed to acid hydrolysis of "colloidal" phosphorus. Microparticulate apatite also has the potential to release soluble reactive phosphate when the acidic molybdenum blue method is used.

Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

1982 ◽  
Vol 47 (03) ◽  
pp. 197-202 ◽  
Author(s):  
Kurt Huber ◽  
Johannes Kirchheimer ◽  
Bernd R Binder
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Human Urine ◽  
Gel Filtration ◽  
Chain Structure ◽  
The Other ◽  
Single Chain ◽  
Apparent Homogeneity ◽  
Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

scholarly journals Characterization of glycoconjugates of human gastrointestinal mucosa by lectins. II. Lectin binding to the isolated glycoproteins of normal and malignant gastric mucosa.

1984 ◽  
Vol 32 (7) ◽  
pp. 690-696 ◽  
Author(s):  
J Fischer ◽  
G Uhlenbruck ◽  
P J Klein ◽  
M Vierbuchen ◽  
R Fischer
Keyword(s):  
Molecular Weight ◽  
Gastric Mucosa ◽  
High Molecular Weight ◽  
Lectin Binding ◽  
Gel Filtration ◽  
Molar Ratio ◽  
Gastric Cancer Cells ◽  
Tissue Sections ◽  
Gradient Gel Electrophoresis ◽  
Triton X

Using affinity chromatography on HPA-, PNA-, Con A, and WGA-agarose columns only a part (10-30%) of the high molecular weight mucous glycoproteins could be isolated from the Triton X-100 solubilized components of normal as well as carcinomatous gastric mucosa. The main part of the mucus was not bound by the lectins, which corresponds to our earlier lectin histochemical observations on paraffin-embedded tissue sections. The lectin-bound mucous glycoproteins had a relatively lower molecular weight, ranging from about 250-1,000 kilodaltons, as indicated by polyacrylamide gradient gel electrophoresis and by gel filtration on Biogel A 1.5 m column. In gas chromatographic analysis the molar ratio of aminohexoses to galactose was found to be much higher (3:1) in the lectin-bound mucous substances than in the whole high molecular weight mucus (1:1). This finding indicates that lectins have a higher affinity to the hexosamine rich components of mucus, which may be special forms of mucous glycoprotein molecules or the incompletely glycosylated core and backbone regions of the oligosaccharide chains of mucus. Extremely high hexosamine values (10:1) were found in the PNA isolated mucus of gastric adenocarcinoma. Since it is known that PNA binds to the terminal disaccharide, beta-galactose-(1-3)-N-acetylgalactosamine, which is localized at the reducing end of the oligosaccharide chains of mucus, it is highly probable that the elongation of the oligosaccharide side chains is disturbed in gastric cancer cells.

Interaction of high molecular weight kininogen binding proteins on endothelial cells

2004 ◽  
Vol 91 (01) ◽  
pp. 61-70 ◽  
Author(s):  
Baby Tholanikunnel ◽  
Berhane Ghebrehiwet ◽  
Allen Kaplan ◽  
Kusumam Joseph
Keyword(s):  
Molecular Weight ◽  
Endothelial Cell ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Surface Proteins ◽  
Factor Xii ◽  
High Molecular Weight Kininogen ◽  
Dot Blot ◽  
Cell Plasma ◽  
Molecular Weight Peak

SummaryCell surface proteins reported to participate in the binding and activation of the plasma kinin-forming cascade includes gC1qR, cytokeratin 1 and u-PAR. Each of these proteins binds high molecular weight kininogen (HK) as well as Factor XII. The studies on the interaction of these proteins, using dot-blot analysis, revealed that cytokeratin 1 binds to both gC1qR and u-PAR while gC1qR and u-PAR do not bind to each other. The binding properties of these proteins were further analyzed by gel filtration. When biotinylated cytokeratin 1 was incubated with either gC1qR or u-PAR and gel filtered, a new, higher molecular weight peak containing biotin was observed indicating complex formation. The protein shift was also similar to the biotin shift. Further, immunoprecipitation of solubilized endothelial cell plasma membrane proteins with anti-gC1qR recovered both gC1qR and cytokeratin 1, but not u-PAR. Immunoprecipitation with anti-u-PAR recovered only u-PAR and cytokeratin 1. By competitive ELISA, gC1qR inhibits u-PAR from binding to cytokeratin 1; u-PAR inhibits gC1qR binding to a lesser extent and requires a 10-fold molar excess. Our data suggest that formation of HK (and Factor XII) binding sites along endothelial cell membranes consists of bimolecular complexes of gC1qR-cytokeratin 1 and u-PAR-cytokeratin 1, with gC1qR binding being favored.

scholarly journals High Molecular Weight Factor VIII Coagulant Activity in Cryoprecipitate and Polyethylene Glycol Precipitates

1977 ◽  
Author(s):  
K. A. Rickard ◽  
T. Exner ◽  
H. Kronenberg
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Factor Viii ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Lower Molecular Weight ◽  
Human Antibody ◽  
High Molecular Weight Material ◽  
Coagulant Activity ◽  
Molecular Weight Form

Gel filtration of human plasma cryoprecipitate on Sepharose 2B indicated the molecular weight of factor VIII coagulant activity (VIIIc) to be significantly greater than that found in antihaemophilic concentrate. Polyethylene glycol at 3% concentration precipitated approximately half of the VIIIc from cryoprecipitate. This activity eluted as high molecular weight material on gel filtration. The addition of more polyethylene glycol to a concentration of 8% precipitated most of the remaining VIIIc from cryoprecipitate. This activity appeared to be of significantly lower molecular weight, approximately corresponding in elution volume to that observed for antihaemophilic concentrate. The possibility that an antibody to VIIIc generated in a patient treated with cryoprecipitate might be directed against the higher molecular weight form of factor VIII was investigated. However, no significant differences between the higher and lower molecular weight forms of factor VIII either in stability or in reactivity with human antibody to factor VIII were found.

Human High Molecular Weight Kininogen - A Secreted Platelet Coagulant Protein

1981 ◽  
Author(s):  
A H Schmaier ◽  
J Kuchibhotla ◽  
R W Colman
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Human Platelets ◽  
Metabolic Inhibitors ◽  
Ionophore A23187 ◽  
High Molecular Weight Kininogen ◽  
Contact Phase ◽  
Platelet Factor ◽  
Coagulant Activity

Platelets have been shown to contain a number of secret- able coagulant proteins, which participate as substrates or cofactors in plasma coagulation reactions. Since we have previously demonstrated that high molecular weight kininogen (HMWK) is immunochemically present in platelet extracts, we posited that HMWK is secreted during activation of platelets. Fresh normal platelets were washed by a combination of albumin-gradient and gel-filtration procedures. In 11 experiments the supernates of freeze-thaw lysates of normal human platelets contained a mean of 5.7 Units (range 3.16 to 8.14) of HMWK coagulant activity/3 × 1011 platelets. This coagulant activity was neutralized by a goat antiki- ninogen antibody. Using a 125I-HMWK tracer in PRP, the supernate of washed activated platelets contained 0.082% radioactivity as the starting PRP, suggesting that 14% of the total HMWK coagulant activity could be accounted for by plasma contamination. In four experiments, ionophore A23187 (15μM) induced a net secretion of 39% of the total platelet HMWK (range 16 to 49%). Platelet HMWK secretion by A23187 was concentration dependent (1 to 15 μM) . At A23187 (15μM) platelets released 75% 14C-5HT (range 61 to 99%) and 81% low affinity platelet Factor 4 (range 60 to 99%). Ninety-five percent of A23187-induced secretion of HMWK could be blocked by platelet pretreatment with metabolic inhibitors. LDH determinations indicated that only 5% (range 0 to 10%) of total secreted platelet HMWK could be attributed to lysis. Collagen and PGH2 also caused secretion of platelet HMWK coagulant activity. This study indicates that human platelets contain functional HMWK which may be secreted locally to modulate the reactions of the contact phase of plasma proteolysis.

scholarly journals Biodegradation of low molecular weight polyacrylamide under aerobic and anaerobic conditions: effect of the molecular weight

2020 ◽  
Vol 81 (2) ◽  
pp. 301-308 ◽  
Author(s):  
Wenzhe Song ◽  
Yu Zhang ◽  
Amir Hossein Hamidian ◽  
Min Yang
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Carbon Chain ◽  
Anaerobic Treatment ◽  
Low Molecular Weight ◽  
Amino Groups ◽  
Molecular Weights ◽  
Weight One ◽  
Hydrolysis Of ◽  
Aerobic And Anaerobic

Abstract The biodegradation of polyacrylamide (PAM) includes the hydrolysis of amino groups and cleavage of the carbon chain; however, the effect of molecular weight on the biodegradation needs further investigations. In this study, biodegradation of low molecular weight PAM (1.6 × 106 Da) was evaluated in two aerobic (25 °C and 40 °C) and two anaerobic (35 °C and 55 °C) reactors over 100 days. The removal of the low molecular weight PAM (52.0–52.6%) through the hydrolysis of amino groups by anaerobic treatment (35 °C and 55 °C) was much higher than that of the high molecular weight (2.2 × 107 Da, 11.2–17.0%) observed under the same conditions. The molecular weight was reduced from 1.6 × 106 to 6.45–7.42 × 105 Da for the low molecular weight PAM, while the high molecular weight PAM declined from 2.2 × 107 to 3.76–5.87 × 106 Da. The results showed that the amino hydrolysis of low molecular weight PAM is easier than that of the high molecular weight one, while the cleavage of its carbon chain is still difficult. The molecular weights of PAM in the effluents from the two aerobic reactors (25 °C and 40 °C) were further reduced to 4.31 × 105 and 5.68 × 105 Da by the biofilm treatment, respectively. The results would be useful for the management of wastewater containing PAM.

scholarly journals Complex Formation of Covalently Crosslinked Fibrin Oligomers with Agarose Coupled Fibrinogen and Fibrin

1977 ◽  
Author(s):  
R. von Hugo ◽  
R. Hafter ◽  
A. Stemberger ◽  
H. Graeff
Keyword(s):  
Molecular Weight ◽  
Complex Formation ◽  
Affinity Chromatography ◽  
High Molecular Weight ◽  
Calcium Chloride ◽  
Gel Filtration ◽  
Void Volume ◽  
Soluble Fibrin ◽  
Derivatives Of

Crosslinked high molecular weight derivatives of fibrin (fibrinoligomers) were observed during intravascular coagulation. It was the purpose of this study to investigate the complex formation of fibrin oligomers with fibrinogen and fibrinmonomer. Fibrinogen coupled to agarose (Fg-ag) as well as fi-brinmonomer coupled to agarose (Fm-ag) was used as substrate. Soluble oligomers of fibrin were produced by incubating fibrinogen with thrombin, calcium-chloride, cystein and F XIII. They were separated from fibrinogen by gel filtration. Γ-dimers were demonstrated in fractions from the void volume and the shoulder prior to the fibrinogen peak. These fractions were subjected to affinity chromatography. Crosslinked oligomers of fibrin were not adsorbed on Fg-ag, yet adsorption occured on Fm-ag. This indicates that fibrin oligomers have no affinity to fibrinogen, yet readily form complexes with fibrin. This could mean that in vivo they compete with fibrinogen for the fibrinmonomer part of soluble fibrin monomer complexes, and hence have a tendency to increase in size.

Gel Filtration of Plasma from Rabbits Injected with Honomeric DES-AB 125I-Fibrin and 131I–Fibrinogen

1979 ◽  
Author(s):  
I. Kröhnke ◽  
I. Hahn ◽  
W. Krell ◽  
G. Müller-Berghaus
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Void Volume ◽  
Molecular Configuration ◽  
Chromatographic Behaviour ◽  
Fibrin Monomer ◽  
Deutsche Forschungsgemeinschaft

We intended to study the chromatographic behaviour of soluble des-AB fibrin prepared in vitro and injected into rabbits. To prepare des-AB 1251-fibrin, purified rabbit 125I-fibrinogen was clotted by thrombin and the formed clot dissolved in Tris-buffered 3 M urea. Gel filtration of des-AB fibrin in urea through sepharose-CL 6B columns equilibrated with buffered 3 M. urea revealed monomeric fibrin. Rabbits received 131I-fibrinogen and 5 min later monomeric des-AB 125I-fibrin in urea. 30 min after injection blood was drawn and the plasma obtained filtered through sepharose-CL 6B columns eguilibrated with buffered plasma. At 20°C as well as at 37°C des-AB 125I-fibrin was eluted in the void volume in front of the 131I-fibrinogen peak. The data demonstrate that monomeric des-AB 125I-fibrin in urea injected into rabbits remains soluble in plasma. Possibly, monomerJ fibrin is converted to circulating soluble high-molecular weight fibrin aggregates or fibrin monomer changes its molecular configuration, thus showing a different gel filtration behaviour.(Supported by the Deutsche Forschungsgemeinschaft).

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