These include (1) tetrahydrobiopterin (BH 4 ), synthesized by the GTP cyclohydrolase 1 (GCH1)6-pyruvoyl-tetrahydropterin synthase (PTS)sepiapterin reductase (SPR) metabolic pathway and regenerated by dihydrofolate reductase (DHFR) 11
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Media Attributions Figure 11.1.1 Steven Earle, CC BY SA 4.0, after Water Cycle by Ingwik, CC BY SA 3.0, via Wikimedia Commons, Figure 11.1.2 Steven Earle, CC BY 4.0 Figure 11.1.3 Modified by Steven Earle, from Mackenzie River with Heavy Sediment Load by Pierre Markuse, 2018, CC BY 2.0 via Flickr,
EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS), Mortensen A, Aguilar F, Crebelli R, Di Domenico A, Dusemund B, Frutos MJ, et al: Re-evaluation of glutamic acid (E 620), sodium glutamate (E 621), potassium glutamate (E 622), calcium glutamate (E 623), ammonium glutamate (E 624) and magnesium glutamate (E 625) as food additives