Results 21 to 30 of about 15,789 (137)
A search for mid-IR bands of amino acids in the Perseus Molecular Cloud [PDF]
arXiv, 2023 Amino acids are building-blocks of proteins, basic constituents of all organisms and essential to life on Earth. They are present in carbonaceous chondrite meteorites and comets, but their origin is still unknown. We present Spitzer spectroscopic observations in the star-forming region IC 348 of the Perseus Molecular Cloud showing the possible ...
arxiv
CPMD simulation of Cu2+ -- phenylalanine complex under micro-solvated environment [PDF]
arXiv, 2013 The study combines DFT calculations and CPMD simulations to investigate the structures of phenylalanine-copper (II) ([Phe-Cu]2+) complexes and the micro-solvation processes. ....It is found that the phenylalanine moiety appears to be in the neutral form in isolated and mono-hydrated complexes, but in the zwitterionic form in other hydrated complexes ...
arxiv
THz to far-infrared spectra of the known crystal polymorphs of Phenylalanine [PDF]
There is renewed interest in the structure of the essential amino acid Phenylalanine in the solid state. Three new polymorphs were found in the years 2012 to 2014. Here, we investigate the structure, stability, and energetical ordering of these phases using first-principles simulations at the level of Density Functional Theory incorporating van-der ...
arxiv +1 more source
Ultrafast Charge Migration in XUV Photoexcited Phenylalanine: a First-Principles Study Based on Real-Time Nonequilibrium Green's Functions [PDF]
Journal of Physical Chemistry Letters 9, 1353 (2018), 2018 The early stage density oscillations of the electronic charge in molecules irradiated by an attosecond XUV pulse takes place on femto- or subfemtosecond timescales. This ultrafast charge migration process is a central topic in attoscience as it dictates the relaxation pathways of the molecular structure.
arxiv
Effects of Ingestion of Excess Amounts of Phenylalanine on Phenylalanine Metabolism
The Japanese Journal of Nutrition and Dietetics, 1973 The effects of nutritional and hormonal treatments on the activities of rat liver phenylalanine hydroxylase (Phe H) were studied. When a non-protein diet was substituted for the high protein diet, Phe H activities fell rapidly and remained constant from Day 7, whereas when rats were starved for 10 days, Phe H activities were slightly decreased. In case
openaire +4 more sources
Effect of glucagon on phenylalanine metabolism and phenylalanine-degrading enzymes in the rat [PDF]
Biochemical Journal, 1974 Glucagon administered subcutaneously to rats for 10 days had no significant effect on liver phenylalanine hydroxylase activity, but induced liver dihydropteridine reductase more than twofold. In rats administered a phenylalanine load orally, glucagon treatment stimulated oxidation and depressed urinary phenylalanine excretion. These responses could not
Larry M. Brand, Alfred E. Harper
openaire +3 more sources
From building blocks of proteins to drugs: A quantum chemical study on structure-property relationships of phenylalanine, tyrosine and dopa [PDF]
arXiv, 2014 Density functional theory and ab initio methods have been employed to address the impacts of hydroxyl (OH) group substitutions on the physico-chemical properties of levodopa (or L-dopa) against the natural amino acids, phenylalanine and tyrosine. L-dopa, which is an important therapeutic drug for Parkinson's disease, shares structural homology with the
arxiv
A New DNA Sequences Vector Space on a Genetic Code Galois Field [PDF]
The final version of the paper is published in the journal: MATCH
Commun. Math. Comput. Chem. Volume 54 (2005), number 1 , pp. 3-28., 2004 A new n-dimensional vector space of the DNA sequences on the Galois field of the 64 codons (GF(64)) is proposed. In this vector space gene mutations can be considered linear transformations or translations of the wild type gene. In particular, the set of translations that preserve the chemical type of the third base position in the codon is a subgroup ...
arxiv
A Novel Lie Algebra of the Genetic Code over the Galois Field of Four DNA Bases [PDF]
arXiv, 2005 By starting from the four DNA bases order in the Boolean lattice, a novel Lie Algebra of the genetic code is proposed. Here, the principal partitions of the genetic code table were obtained as equivalent classes of quotient subspaces of the genetic code vector space over the Galois field of the four DNA bases.
arxiv
Biochemistry, 2014 Analytical ultracentrifugation has been used to analyze the oligomeric structure of the isolated regulatory domain of phenylalanine hydroxylase. The protein exhibits a monomer-dimer equilibrium with a dissociation constant of ~46 μM; this value is unaffected by the removal of the 24 N-terminal residues or by phosphorylation of Ser16.
Paul F. Fitzpatrick +2 more
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