INHIBITION OF IN VITRO ACETOACETATE FORMATION: AN ACID PHOSPHOHYDROLASE

1965 ◽  
Vol 43 (6) ◽  
pp. 731-745 ◽  
Author(s):  
Ian C. Caldwell ◽  
George I. Drummond
Keyword(s):  
Metal Binding ◽  
Protein Concentration ◽  
Coenzyme A ◽  
Chicken Liver ◽  
Phosphate Esters ◽  
Acetyl Phosphate ◽  
Tissue Extracts ◽  
Binding Agents ◽  
Enzymatic Inactivation

The rate of formation of acetoacetate in vitro by tissue extracts from acetyl phosphate and coenzyme A in the presence of phosphate transacetylase and β-ketothiolase is proportional to protein concentration with extracts of most tissues. However, studies with chicken liver extracts are complicated by the presence in these extracts of a factor which interferes with acetoacetate formation. This factor has been identified as an acid phosphohydrolase which hydrolyzes the phosphate monoester bond of coenzyme A, forming the inactive 3′-dephosphocoenzyme A. This enzyme has been purified 300-fold from chicken liver extracts, and some of its properties have been examined. The rate of inactivation of coenzyme A by the enzyme is neither enhanced by divalent cation nor inhibited by metal-binding agents. Enzymatic inactivation of coenzyme A is optimal at pH 3.6, with half-maximal rates observed at pH 5.5 and below pH 2.5. The most highly purified enzyme fraction exhibited phosphohydrolase activity against a wide variety of phosphate esters. Some evidence was obtained to suggest that the coenzyme A phosphohydrolase could be separated from nonspecific acid phosphohydrolase.

Zinc Enzymes in Crassostrea virginica

1970 ◽  
Vol 27 (1) ◽  
pp. 59-69 ◽  
Author(s):  
Douglas A. Wolfe
Keyword(s):  
Alkaline Phosphatase ◽  
Metal Binding ◽  
Zinc Enzymes ◽  
Tissue Extracts ◽  
Metabolic Functions ◽  
Binding Agents ◽  
High Molecular Weight Proteins ◽  
Cellular Components ◽  
Inhibition Studies

Nearly all the zinc in oysters is bound, either to soluble high-molecular weight proteins or to structural cellular components such as cell membranes. Oyster alkaline phosphatase is a zinc metalloenzyme, as indicated by in vitro inhibition studies with various metal-binding agents. Dialysis of soluble tissue extracts at pH 7–9 removes up to 96% of the total zinc without effect on alkaline phosphatase. If alkaline phosphatase is considered representative of the metabolic functions of zinc in oysters, most of the zinc accumulated by oysters must be superfluous to the animal's requirements.

Dithiol metal binding agents — Efficacies and properties in vivo and in vitro

1983 ◽  
Vol 18 ◽  
pp. 161
Author(s):  
R. Maiorino ◽  
C.A. Hsu ◽  
E.R. Stine ◽  
T.D. Hoover ◽  
H.V. Aposhian
Keyword(s):  
Metal Binding ◽  
Binding Agents

In Vitro Immunodetection of Prothymosin Alpha in Normal and Pathological Conditions

2020 ◽  
Vol 27 (29) ◽  
pp. 4840-4854 ◽  
Author(s):  
Chrysoula-Evangelia Karachaliou ◽  
Hubert Kalbacher ◽  
Wolfgang Voelter ◽  
Ourania E. Tsitsilonis ◽  
Evangelia Livaniou
Keyword(s):  
Mammalian Cells ◽  
Therapeutic Potential ◽  
Prothymosin Alpha ◽  
Disease States ◽  
Leading Role ◽  
Tissue Extracts ◽  
Biologic Response ◽  
Health And Disease ◽  
Almost All

Prothymosin alpha (ProTα) is a highly acidic polypeptide, ubiquitously expressed in almost all mammalian cells and tissues and consisting of 109 amino acids in humans. ProTα is known to act both, intracellularly, as an anti-apoptotic and proliferation mediator, and extracellularly, as a biologic response modifier mediating immune responses similar to molecules termed as “alarmins”. Antibodies and immunochemical techniques for ProTα have played a leading role in the investigation of the biological role of ProTα, several aspects of which still remain unknown and contributed to unraveling the diagnostic and therapeutic potential of the polypeptide. This review deals with the so far reported antibodies along with the related immunodetection methodology for ProTα (immunoassays as well as immunohistochemical, immunocytological, immunoblotting, and immunoprecipitation techniques) and its application to biological samples of interest (tissue extracts and sections, cells, cell lysates and cell culture supernatants, body fluids), in health and disease states. In this context, literature information is critically discussed, and some concluding remarks are presented.

scholarly journals Chromatography-Independent Fractionation and Newly Identified Molecular Features of the Adzuki Bean (Vigna angularis Willd.) β-vignin Protein

2021 ◽  
Vol 22 (6) ◽  
pp. 3018
Author(s):  
Biane Philadelpho ◽  
Victória Souza ◽  
Fabiani Souza ◽  
Johnnie Santos ◽  
Fabiana Batista ◽  
...  
Keyword(s):  
Metal Binding ◽  
Cardiovascular Health ◽  
Binding Capacity ◽  
Biological Activities ◽  
Electrophoretic Analysis ◽  
Adzuki Bean ◽  
Molecular Features ◽  
Health Promoting ◽  
High Degree

Adzuki seed β-vignin, a vicilin-like globulin, has proven to exert various health-promoting biological activities, notably in cardiovascular health. A simple scalable enrichment procedure of this protein for further nutritional and functional studies is crucial. In this study, a simplified chromatography-independent protein fractionation procedure has been optimized and described. The electrophoretic analysis showed a high degree of homogeneity of β-vignin isolate. Furthermore, the molecular features of the purified protein were investigated. The adzuki bean β-vignin was found to have a native size of 146 kDa, and the molecular weight determined was consistent with a trimeric structure. These were identified in two main polypeptide chains (masses of 56–54 kDa) that are glycosylated polypeptides with metal binding capacity, and one minor polypeptide chain with a mass 37 kDa, wherein these features are absent. The in vitro analysis showed a high degree of digestibility of the protein (92%) and potential anti-inflammatory capacity. The results lay the basis not only for further investigation of the health-promoting properties of the adzuki bean β-vignin protein, but also for a possible application as nutraceutical molecule.

Role of calcium and calcium-binding agents on the lipase digestibility of emulsified lipids using an in vitro digestion model

2010 ◽  
Vol 24 (8) ◽  
pp. 719-725 ◽  
Author(s):  
Min Hu ◽  
Yan Li ◽  
Eric Andrew Decker ◽  
David Julian McClements
Keyword(s):  
Calcium Binding ◽  
In Vitro Digestion ◽  
Binding Agents
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