Experiments were conducted to determine the tryptophan (Trp) requirement of 10- to 20-kg pigs. A Trp-deficient experimental diet (.11% total Trp, 18% CP, 3,320 kcal of ME/kg) was composed of corn, feather meal, corn gluten meal, soybean meal, and dried whey. True digestibility of Trp in the experimental diet was 70% (.077% digestible Trp) as established in a digestibility assay that involved ce...

This study was conducted to evaluate the effects of oral tryptophan (Trp) supplementation on exercise capacity and metabolic responses in horses. Three horses had to perform an exercise test: a 15-min warm-up followed by a 60-min walk (1.7 m/s, W1), a 10-min trot (3.1 m/s, T1), a second 60-min walk (1.7 m/s, W2), a second 10-min trot (3.1 m/s, T2) and a final 30-min walk (1.7 m/s, W3) until the...

Holzer and Holzer [7] proved that the TantrixTM rotation puzzle problem with four colors is NP-complete, and they showed that the infinite variant of this problem is undecidable. In this paper, we study the three-color and two-color TantrixTM rotation puzzle problems (3-TRP and 2-TRP) and their variants. Restricting the number of allowed colors to three (respectively, to two) reduces the set of...

Tryptophan (Trp) requirements in pregnancy are several-fold: (1) the need for increased protein synthesis by mother and for fetal growth and development; (2) serotonin (5-HT) for signalling pathways; (3) kynurenic acid (KA) for neuronal protection; (4) quinolinic acid (QA) for NAD(+) synthesis (5) other kynurenines (Ks) for suppressing fetal rejection. These goals could not be achieved if mater...

Synopsis Tryptophan (Trp) requirements in pregnancy are several-fold: (1) the need for increased protein synthesis by mother and for fetal growth and development; (2) serotonin for signaling pathways; (3) kynurenic acid for neuronal protection; (4) quinolinic acid for NAD synthesis (5) other kynurenines for suppressing fetal rejection. These goals could not be achieved if maternal plasma [Trp] ...

Indole-3-acetic acid (IAA) plays a critical role in regulating numerous aspects of plant growth and development. While there is much genetic support for tryptophan-dependent (Trp-D) IAA synthesis pathways, there is little genetic evidence for tryptophan-independent (Trp-I) IAA synthesis pathways. Using Arabidopsis, we identified two mutant alleles of ISS1 ( I: ndole S: evere S: ensitive) that d...

In the present study, modified nucleotides in the B. subtilis tRNA(Trp) cloned and hyperexpressed in E. coli have been identified by TLC and HPLC analyses. The modification patterns of the two isoacceptors of cloned B. subtilis tRNA(Trp) have been compared with those of native tRNA(Trp) from B. subtilis and from E. coli. The modifications of the A73 mutant of B. subtilis tRNA(Trp), which is ina...

We hypothesize that: (1) L-tryptophan (Trp) is greatly utilized and not depleted in pregnancy; (2) fetal tolerance is achieved in part through immunosuppressive kynurenine (Kyn) metabolites produced by the flux of plasma free (non-albumin-bound) Trp down the Kyn pathway; (3) the role of indoleamine 2,3-dioxygenase (IDO) in infection is not related to limitation of an essential amino acid, but i...

To test features of the current model of transcription attenuation in amino acid biosynthetic operons, alterations were introduced into the trp operon leader region and expression of the mutated operons was examined in miaA and miaA+ Escherichia coli strains that lacked the trp repressor. The miaA mutation prevents modification of the adenosine residue immediately 3' of the anticodon of tRNAs t...

Skin and hair colour mostly depend on the activity of melanogenic melanocytes. Numerous proteins involved in melanocyte function have been identified including pMel-17, Mitf-M, Sox10, tyrosinase, tyrosinase related proteins-1 (TRP-1) and -2 (TRP-2). In the hair, melanogenic activity occurs only during the anagen phase of the hair cycle. In order to evaluate the implications of some known melano...