From the lifetimes of the individual RNAP DNA complexes, two distinct types of RPc were discovered: a short-lived RPc with a lifetime of 2.3 ± 0.5 s that is a precursor of a longer lived RPc, which has a lifetime of 79 ± 13 s.
Folate plays an essential role in one-carbon metabolism involving remethylation of homocysteine to methionine, which is a precursor of S-adenosylmethionine, the primary methyl group donor for most biological methylations, including DNA methylation.
Barrett's esophagus is a precursor of esophageal adenocarcinoma, both of which are associated with GERD.
At about 70,000 years ago a blade-based industry called Howieson's Poort begins; this industry is a precursor of Upper Paleolithic technology.
But Ed Stansfield of the consultancy Capital Economics thinks February's price fall is a precursor of worse to come: "The correction we saw in 2008 and the beginning of 2009 is probably not over yet," he said.
If last week's fighting in Baghdad is a precursor of a more violent stand-off to come, then the US may find its smooth exit from the country rudely interrupted.
Furthermore, blood levels of DHEA-S, a precursor of androgen and estrogen, exhibited mouse-specific elevation, which may also contribute to endocrine system disruption.
Homocysteine is biosynthesized by the MHM in a process involving the donation of a methyl group by S-adenosylmethionine (SAM), which in turn gets converted into S-adenosylhomocysteine (SAH), a precursor of homocysteine.
(S -α-acetolactate, a precurS -α-acetolactate leucine, can be made from two moleculeS -α-acetolactatea biosynthetic-typrecursorse (Pcar_1910) with a regulatofy subunit (Pcar_1909), but a fermentativalinehwandrequires an additionaleucineolicanype (S)-α-acetolactate synthase.
GSH can also conjugate L-dopaquinone in the presence of glutathione S-transferase and yield glutathionyldopa, a precursor of cysteinyldopa.
Methionine functions as a precursor of S-adenosyl methionine (SAM) and a main methyl donor that is important for a variety of methyltransferase reactions [ 4].
