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The jet-cooled ultraviolet direct absorption spectrum of the amino acid tryptophan is reported. The spectrum measured by cavity ring-down laser absorption spectroscopy covers the region where the origin bands of the S(1) <-- S(0) transitions of six conformers (A to F) are located. Tryptophan was
Melatonin has been shown to regulate several immune functions, and some authors showed that leukocytes are also able to produce the indolamine. In fact, it seems to take part in some immunoregulatory axis, including that related to interferon (IFN) production. So, we evaluated the rate of tryptophan
Human α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (hACMSD) is a zinc containing amidohydrolase which is a vital enzyme of the kynurenine pathway in tryptophan metabolism. It prevents the accumulation of quinolinic acid (QA) and helps in the maintenance of basal Trp-niacin ratio. To assess
Inteins mediate protein splicing, which has found extensive applications in protein science and biotechnology. In the Mycobacterium tuberculosis RecA mini-mini intein (ΔΔIhh), a single valine to leucine substitution at position 67 (V67L) dramatically increases intein stability and activity. However,
HIV-1-infected cells presenting envelope glycoproteins (Env) in the CD4-bound conformation on their surface are preferentially targeted by antibody-dependent cellular-mediated cytotoxicity (ADCC). HIV-1 has evolved sophisticated mechanisms to avoid the exposure of Env ADCC epitopes by downregulating
As an extension of our studies on the interaction of detergents with membranes and membrane proteins, we have investigated their binding to water-soluble proteins. Anionic aliphatic compounds (dodecanoate and dodecylsulfate) were bound to serum albumin with high affinity at nine sites; related
In order to elucidate the thermo-stabilization mechanism of the tryptophan synthase alpha-subunit from the extreme thermophile Thermus thermophilus HB8 (Tt-alpha-subunit), its crystal structure was determined and its stability was examined using DSC. The results were compared to those of other
Targeting protein-protein interacting sites for potential therapeutic applications is a challenge in the development of inhibitors, and this becomes more difficult when these interfaces are relatively planar, as in the eukaryotic translation initiation factor 4E (eIF4E) protein. eIF4E is an oncogene
To investigate the molecular basis of cold adaptation of enzymes, we determined the crystal structure of the tryptophan synthase α subunit (SfTSA) from the psychrophile Shewanella frigidimarina K14-2 by X-ray analysis at 2.6-Å resolution and also examined its physicochemical properties. SfTSA was
The M2 proton channel of the influenza A virus has been the subject of extensive studies because of its critical role in viral replication. As such, we now know a great deal about its mechanism of action, especially how it selects and conducts protons in an asymmetric fashion. The conductance of
Vertebrate odorant-binding proteins (OBPs) are small extracellular proteins belonging to the lipocalin superfamily. They have been supposed to play a role in events of odorant molecules detection by carrying, deactivating, and/or selecting odorant molecules. The OBPs share a conserved folding
An activation study of mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms I-XIV with D- and L-tryptophan has been performed both by means of kinetic and X-ray crystallographic techniques. These compounds show a time dependent activity against isozyme CA II, with activation constants of 1.13
Foxp3+ regulatory T (Treg) cells contribute to the local dysfunctional immune environment in endometriosis, an estrogen-dependent gynecological disease, which affects the function of ectopic endometrial tissue clearance by the immune system. The reason for the high percentage of peritoneal Treg in