Question

Explain the formation of $B{H_4}^ -$ .

Answer 1

Hint : In order to this question, to know the explanation of the formation of $B{H_4}^ -$ , we should got through the whole concept or mechanism of $B{H_4}^ -$ or Tetrahydrobiopterin and also we will discuss more about it.

Complete Step By Step Answer:
$B{H_4}^ -$ is formed from the abundant, simple molecule GTP in a three-step process, each step catalyzed by a different enzyme; GTP cyclohydrolase I (encoded for by the gene GCH1), pyruvoyl tetrahydropterin synthase (PTS) and sepiapterin reductase (SPR).Pathological mutations in any of these genes can lead to $B{H_4}^ -$ deficiency, it is not yet clear if there are polymorphisms that result in milder reductions in function.
$B{H_4}^ -$ is an important cofactor for several enzymes including nitric oxide synthase $({\mathbf{NOS}})1 - 3$ which are responsible for converting arginine into nitric oxide.
$B{H_4}^ -$ is also the cofactor for tryptophan hydroxylase (TPH), which converts tryptophan into the neurotransmitter serotonin. You’ve very likely heard of serotonin, it plays an important role in regulating muscle movement and mood.

Note :
$B{H_4}^ -$ is the cofactor used by phenylalanine hydroxylase in the conversion of phenylalanine into tyrosine, and its subsequent conversion by tyrosine hydroxylase (TH) into DOPA, the dopamine precursor. Dopamine is an important neurotransmitter in its own right, but it can also be converted into norepinephrine and epinephrine, the enzymes which control these reactions both use $B{H_4}^ -$ as a cofactor.