Jan 2, 1976

Pyrophosphatase and glucuronosyltransferase in microsomal UDPglucuronic-acid metabolism in the rat liver

European Journal of Biochemistry
E Puhakainen, O Hänninen

Abstract

1. A radiochemical method for the studies on the microsomal UDPglucuronic acid metabolism has been developed. 2. The rat liver microsomes caused a rapid hydrolysis of UDPglucuronic acid to D-glucuronic acid 1-phosphate and further although much slower to free D-glucuronic acid. In Tris-HCl buffer (pH 7.4) they were produced in ratio 72 : 1. No other metabolites were found in measurable amounts. The pyrophosphatase splitting UDPglucuronic acid showed a pH optimum at 8.9, but the liberation of D-glucuronic acid from UDPglucuronic acid had two pH maxima (pH 3.5 and 8.5). EDTA appeared to be less powerful inhibitor of pyrophosphatase than previously suggested. About 25 per cent of the UDPglucuronic acid hydrolyzing activity was still remaining in the presence of 10 mM EDTA. D-Glucaro-1,4-lactone was found to have a slight inhibitory action on the pyrophosphatase activity. Citrate inhibited powerfully the hydrolysis of UDPglucuronic acid and the liberation of free D-glucuronic acid. Phosphate was also inhibitory. 3. In the presence of an exogenous UDPglucuronosyltransferase substrate, 4-nitrophenol, the formation of D-glucuronic acid 1-phosphate and free D-glucuronic acid were slightly reduced, and D-glucuronic acid 1-phosphate, 4-n...Continue Reading

  • References9
  • Citations7

Mentioned in this Paper

4-nitrophenylglucuronide
Uridine Diphosphate Glucuronic Acid
Metabolic Process, Cellular
Pyrophosphatase
Conjugation
Glucuronosyltransferase
Ugt2b
Tromethamine
Beta-glucuronidase
Citrate Measurement

About this Paper

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Synthetic Genetic Array Analysis

Synthetic genetic arrays allow the systematic examination of genetic interactions. Here is the latest research focusing on synthetic genetic arrays and their analyses.

Autism: Motor Learning

A common feature of autism spectrum disorder (ASD) is the impairment of motor control and learning, consistent with perturbation in cerebellar function. Find the latest research on ASD and motor learning here.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

Sexual Dimorphism in Neurodegeneration

There exist sex differences in neurodevelopmental and neurodegenerative disorders. For instance, multiple sclerosis is more common in women, whereas Parkinson’s disease is more common in men. Here is the latest research on sexual dimorphism in neurodegeneration

Protein Localization in Disease & Therapy

Localization of proteins is critical for ensuring the correct location for physiological functioning. If an error occurs, diseases such as cardiovascular, neurodegenerative disorders and cancers can present. Therapies are being explored to target this mislocalization. Here is the latest research on protein localization in disease and therapy.

Genetic Screens in Bacteria

Genetic screens can provide important information on gene function as well as the molecular events that underlie a biological process or pathway. Here is the latest research on genetic screens in bacteria.

Head And Neck Squamous Cell Carcinoma

Squamous cell carcinomas account for >90% of all tumors in the head and neck region. Head and neck squamous cell carcinoma incidence has increased dramatically recently with little improvement in patient outcomes. Here is the latest research on this aggressive malignancy.

Artificial Intelligence in Cardiac Imaging

Artificial intelligence (ai) techniques are increasingly applied to cardiovascular (cv) medicine in cardiac imaging analysis. Here is the latest research.