What type of inhibitor is L-phenylalanine?
L-Phenylalanine is recognised to be a stereo- specific inhibitor for alkaline phosphatase from a wide variety of mammalian sources [I]. In several instances it has been established that the inhibition is uncompetitive [2-51 and in the absence of contrary evidence we assume the same holds for other tissue isoenzymes.
What kind of inhibitor is Na2HPO4?
The results show that Na2HPO4, Na2HAsO4 and Na2WO4 are competitive inhibitors, L-phenylalanine is an uncompetitive inhibitor, while L-cysteine is a mixed-type inhibitor.
What type of inhibitor is phosphate to alkaline phosphatase?
In the alkaline phosphatase reaction, in which hydrolysis of a wide variety of organic monophosphate esters into the corresponding alcohols (or phenols) and inorganic phosphates occurs, the inorganic phosphate acts as a competitive inhibitor.
How can you reduce alkaline phosphatase?
The alkaline phosphatases have pH optima of about 9.0 and are not generally sensitive to fluoride ion but are inhibited by divalent cation-chelating agents like EDTA (ethylene diamine tetraacetic acid, disodium salt).
Is L-phenylalanine a noncompetitive inhibitor?
l-Phenylalanine is a non-competitive inhibitor of both types of activity of the intestinal preparation, but inhibits neither activity of the liver enzyme. Arsenate is a competitive inhibitor of both activities of both preparations.
Does phosphate inhibit phosphatase?
Phosphate inhibited the enzyme competitively, which demonstrates that inhibition due to phosphate is one of the regulatory factors for enzyme activity. Keywords: Vigna aconitifolia; acid phosphatase; fluoride; inhibition; molybdate; phosphate.
What type of enzyme is alkaline phosphatase?
homodimeric protein enzyme
Alkaline phosphatase (ALP, ALKP, ALPase, Alk Phos) (EC 3.1. 3.1), or basic phosphatase, is a homodimeric protein enzyme of 86 kilodaltons. Each monomer contains five cysteine residues, two zinc atoms and one magnesium atom crucial to its catalytic function, and it is optimally active at alkaline pH environments.
How does EDTA inhibit alkaline phosphatase?
Ethylenediaminetetraacetic acid is a potent metal ion chelator able to sequester metal cations. EDTA can form coordination complexes with these ions, inhibiting their catalytic activity. The goal of this experiment was to empirically determine the concentration and time dependence of EDTA- mediated inactivation of AP.
What are the symptoms of high alkaline phosphatase?
High levels of ALP in your blood may indicate liver disease or certain bone disorders….Signs and symptoms of bone disorders include:
- Bone pain and/or joint pain.
- Enlarged and/or abnormally shaped bones.
- Increased frequency of bone fractures.
Can high alkaline phosphatase be treated?
A reduction in serum ALP was also seen in the euparathyroid subjects (2.4 +/- 0.77 to 2.2 +/- 0.64 mu kat/l, p = 0.03). This study indicates that treatment with active vitamin D is effective in reducing the increased bone turnover seen in subjects with both primary and secondary HPT.
Which isoenzyme of ALP is inhibited by L-phenylalanine?
However, we found that at pH 10.0, with p-nitrophenyl phosphate as the substrate, L-phenylalanine obviously inhibits the alkaline phosphatase isoenzyme from human placenta, whereas there is little if any inhibition of the isoenzyme from human intestine.
What are phosphodiesterase-5 enzymatic inhibitors?
Phosphodiesterase-5 enzyme inhibitors are medications used to treat erectile dysfunction, enlarged prostate ( benign prostate hyperplasia ), and pulmonary arterial hypertension ( PAH ), a condition of high blood pressure in the arteries that carry deoxygenated blood from the heart to the lungs.
How do phosphodiesterase inhibitors work?
Phosphodiesterase inhibitors work by inhibiting the phosphodiesterase enzymes, thus preventing them from breaking down cAMP and cGMP molecules in the cell. The production of cAMP and cGMP are regulated by a molecule called nitric oxide, and their function is to help regulate physiological processes by decreasing the levels of calcium in the cell.
Is caffeine a phosphodiesterase inhibitor?
Caffeine is a phosphodiesterase inhibitor that has been shown to increase the levels of cAMP in the cell thus leading to smooth muscle relaxation. Caffeine is a weak inhibitor, but variations of caffeine including theophylline have been introduced as treatments for pulmonary disease.
What are the possible side effects of phosphodiesterase-5 (P5) inhibitors?
Side effects of phosphodiesterase-5 enzyme inhibitors may include the following: Conjunctival hyperemia (dilation and redness of blood vessels in the conjunctiva, the membrane on the whites of the eyes, and the inner surface of eyelids)