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Three-dimensional solution structure of ascidian trypsin inhibitor exhibits an alpha-helical structure formed by the Cys-X1-X2-X3-Cys segment representing amino acid residues 37-41. Data indicate that the secondary structure and main chain overall folding is similar to those of Kazal-type inhibitors.

Research is presented describing the production of short RNA, incorporating the m7GpppA cap structure, by combining enzymatic synthesis with chemical synthesis. Three capped RNA molecules are synthesized.

Inteins can be used to ligate peptide segments that cannot be visualized by NMR to the ends of an NMR-visible segment. It is difficult to visualize peptides with more than 300 residues because of signal overlapping.

The heat shock sigma factor encoded by the rpoH gene suggests mRNA stability controls transcriptional regulator synthesis. Research with Escherichia coli has shown that heat shock proteins is caused by higher cellular levels of the heat shock sigma factor. It was discovered that partial melting of mRNA enhances ribosome entry without involving other cellular components.

A three-dimensional solution structure of thermostable cytochrome c-552 from Hydrogenobacter thermophilus was determined by proton nuclear magnetic resonance spectroscopy. Twenty structures were calculated and it was found that the main chain folding of the cytochrome c-552 was similar to that of Pseudomonas aeruginosa (PA) cytochrome c-551. The structures of HT c-552 and PA c-551 were compared and structural differences, which may lead to differences in the thermostability between the two proteins, were discovered.

Triple resonance NMR were performed to evaluate the effectiveness of exploiting the 1H(alpha)-13C(alpha) zero/double quantum coherence for assigning the backbone resonance of a large protein. The sample, which was selectively labeled with 1H(alpha) and uniformly labeled with 13C, 15N and 2H, was the C-terminal domain of the alpha subunit of the 98-amino acid RNA polymerase from Escherichia coli.

Anisotropy values of a certain range is shown to result in intense vibrational circular dichroism (VCD) bands for the azide antisymmetric stretching vibration in the azide complex of a C2-chiral strapped iron porphyrin, the first time that an extremely strong VCD band has been measured for the ligand vibration of iron porphyrin without an apo-protein. The generation of the intense VCD bands in hemoproteins can be attributed to a chiral environment produced by the peripheral substituents on the porphyrin ring.

Two DNA duplexes having a DNA.RNA hybrid region, d(GG)r(AGAU)d(GAC).d(GTCATCTCC) (DHD, where D is the DNA segment and H is the DNA.RNA hybrid segment) and d(GGAGA)r(UGAC).d(GTCATCTCC) (DDH) were subjected to nuclear magnetic resonance spectroscopy to show the junctional conformational attributes of D-H and H-D. Completely overlapped H2' and H2' signals of the deoxynucleotide and an increased ribose coupling constant were observed at the D-H junction. Dihedral angles and helical parameters were transformed at the H-D junction but not at the D-H junction.

Sonochemical and triethylborane-induced tin deuteride reduction of ribonucleoside derivative at -60 to -70 degrees celsius generates (2'R)-2'-deoxy(2'-2H)ribonucleoside derivatives with high diastereoselectivity. Reductive deuteration of 3',5'-di-O-benzoyl-2'-bromo-2'-deoxyuridine by Bu3Sn2H in the presence of ultrasound irradiation at -71 degrees celsius produces 3',5'-di-O-benzoyl-2'-deoxy(2'-2H)uridine. With Et3B as a substituted radical generator, (2'R)-2'-deoxy(2'-2H)cytidine derivatives are formed with high diastereoselectivity under similar conditions.

Extensive assignments of the 1H, 15N and 13C resonances of the N-terminal DNA-binding domain of the GAL4 transactivator protein were obtained from two- and three-dimensional heteronuclear NMR experiments and structural studies based on short-, medium- and long-range NOEs, which establish the global fold of the protein. The results indicate that the peptide consists of two short alpha helices. The obtained solution structure is similar to previously determined structures of GAL4.

The vibrational circular dichroism (VCD) enhancement process of the azide ligand was tested by an analysis of the VCD spectrum of azidometmyoglobin (metMbN3) and a reconstituted azidometmyoglobin with an iron-octaethylporphyrin (FeOEP), metMb-(OEP)N3 and different ligand of metMBL (L = SCN-, OCN-, CN- and CO). Antisymmetric stretching of the azide covalently bonded to iron exhibited no VCD band for the metMb(OEP)N3 reconstituted with Fe(OEP).

The disulfide variant of the ovomucoid third domain from silver pheasant, containing the Cys(sup)14-Cys(sup)39 bond, loses much of its inhibitory activity toward elastase but preserves its inhibitory action toward alpha-chymotrypsin and Streptomyces griseus proteases A and B. The inhibitory specificity of the disulfide variant ovomucoid protein is due to a conformational change in the reactive site loop brought about by the disulfide formation.

This article discusses a collaborative facility set-up in Japan for conducting genomics research on membrane proteins. The project envisages developing methodologies for protein structural studies and ligand-receptor interaction employing electron microscopy, X-ray crystallography, nuclear magnetic resonance spectroscopy, and computer simulation.

A study was conducted on a new method for the ligation of labeled and unlabeled peptide fragments using a peptide splicing element, intein. The findings suggest that this method can facilitate the application of NMR to proteins as large as 50 kDa. Although the NMR technique using deuterium labeling is applicable to such proteins, it is difficult because of signal overlap. Segmental labeling facilitates the unambiguous assignment of signals in a shorter time.