Bile acids provide feedback inhibition of CYP7A1 by at least two different pathways, both involving the farnesoid X receptor, FXR . In the liver, bile acids bound to FXR induce Small heterodimer partner, SHP which binds to LRH-1 and so inhibits the transcription of the enzyme.
42.
The inhibition of the enzyme by fructose-1, 6-bisphosphate is most likely a feedback inhibition due to the product of the enzyme ( glucose-1, 6-bisphosphate ) activation of PFK-1 ( the enzyme which produces fructose-1, 6-bisphophate ).
43.
GCL enzymatic activity is influenced by numerous factors, including cellular expression of the GCL subunit proteins, access to substrates ( cysteine is typically limiting in the production of ?-GC ), the degree of negative feedback inhibition by GSH, and functionally relevant post-translational modifications to specific sites on the GCL subunits.
44.
In " E . coli " citrate synthase, the enzyme involved in the condensation reaction initiating the Citric Acid Cycle is strongly inhibited by ?-ketoglutarate feedback inhibition and can be inhibited by DPNH as well high concentrations of ATP . This is one of the initial regulations of the ?-ketoglutarate family of amino acid synthesis.
45.
Taurine crosses the blood brain barrier and has been implicated in a wide array of physiological phenomena including inhibitory neurotransmission, long-term potentiation in the striatum / hippocampus, membrane stabilization, feedback inhibition of neutrophil / macrophage respiratory burst, adipose tissue regulation and possible prevention of obesity, calcium homeostasis, recovery from osmotic shock, protection against glutamate excitotoxicity and prevention of epileptic seizures.
46.
He was the first to detect feedback inhibition of penicillin production by the amino acid lysine . . . and originated the study on the effects of primary metabolites on the secondary metabolism of microorganisms . Demain has said that his work in Rahway showed that over 99 % of the penicillin formed appeared in the liquid portion of the broth and that penicillin was partially degraded during its production.
