Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A description of the efficient high-level expression of the monomer hemoglobin (GMG4) from Glycera dibranchiata is presented. The cDNA described by Simons and Satterlee [Simons, P.C., & Satterlee, J.D. (1989) Biochemistry 28, 8525-8530] was subcloned into an expression system, and conditions were found that led to the production of large amounts of soluble apoprotein (rec-gmg). These conditions included lowering the temperature during the induction period and growth in a rich medium with a higher ionic strength. Characterization of this reconstituted recombinant protein showed that it was not identical to the native GMH4 protein. Both UV-visible and 1H NMR data indicated differences within the holoprotein (rec-gmh) heme pocket compared to the native protein, the major difference being that two nonidentical heme orientations are significantly populated in rec-gmh. This phenomenon has been seen previously in other heme proteins, where these heme orientational isomers are described by a 180-deg rotation about the heme alpha-gamma meso axis. This work prompted the production of a complete chemical sequence for the native GMH4 [Alam S.L., Satterlee, J. D., & Edmonds, C. G. (1994) J. Protein Chem. 13, 151-164], which showed that the expressed rec-gmg protein differed at three primary sequence positions (41, 95, and 123) from the native component IV globin (GMG4). Subsequently, we have produced the triple-revertant mutations required to express the recombinant wild-type protein (recGMG4). The physical characteristics of the active site in the holoprotein (recGMH4) are identical to those of the native protein.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression of recombinant monomer hemoglobins (component IV) from the marine annelid Glycera dibranchiata: evidence for primary sequence positional regulation of heme rotational disorder. 806 70

Data are reported on the structural characterization of 3-methyl-4-oxo-2-phenyl-4H-1-benzopyran-8-carboxylic acid 1,1-dimethyl-2-(N-piperidinyl)ethyl ester hydrochloride (terflavoxate-HCl, Rec 15/2053, CAS 86433-39-8), a new antispasmodic for the lower urinary tract. UV, IR, NMR and MS spectra fully confirmed the structure. The X-ray crystal structure determination revealed that the molecular structure consists of a rigid platform, formed by the chromone system, with two arms, the phenyl group at C(2) and the ester chain at C(8). The ester chain conformation generates a small hollow where two oxygen atoms face.
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PMID:Structural characterization of terflavoxate. 848 68

The ligand behavior of di-2-pyridylketone 2-aminobenzoylhydrazone (Hdpa), and phenyl(2-pyridyl)ketone 2-aminobenzoylhydrazone (Hdba) towards organotin derivatives was investigated. The synthesis and the IR and 119Sn NMR spectroscopic characterization of the compounds is reported, together with the X-ray crystal structures of Hdpa and Sn(C6H5)3Cl(OH2).Hdpa, which are discussed and compared. The in vitro evaluation of antimicrobial properties revealed the strong activity of Sn(C6H5)2(Hdpa)Cl2 and Sn(C6H5)3Cl(OH2).Hdpa complexes. None of the compounds showed genotoxicity in the Bacillus subtilis rec-assay and in the Salmonella-microsome test.
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PMID:Synthesis, structure, and biological activity of organotin compounds with di-2-pyridylketone and phenyl(2-pyridyl) ketone 2-aminobenzoylhydrazones. 853 Sep 20

Mono- and bimetallic organotin complexes with pyrrole-2,5-dicarboxaldehyde bis(2-hydroxybenzoylhydrazone) (H5dfps) and pyrrole-2,5-dicarboxaldehyde bis(2-picolinoylhydrazone) (H3dfpp) were synthesized and characterized by IR, 1H and 119Sn NMR spectroscopy. X-ray analysis of the complex [Sn(H3dfps)(C6H5)2].(CH3)2SO revealed a pentacoordination around tin through a N,N,O terdentate ligand behaviour of the hydrazone. This complex is the most active compound, exhibiting MIC values of 3 and 12 micrograms/ml against Gram positive and Gram negative bacteria, respectively. None of the ligands or complexes produced DNA-damage in the Bacillus subtilis rec-assay or showed mutagenic activity in the Salmonella-microsome test.
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PMID:Organotin complexes with pyrrole-2,5-dicarboxaldehyde bis(acylhydrazones). Synthesis, structure, antimicrobial activity and genotoxicity. 960 41

This study coupled proton magnetic resonance spectroscopy (1H-NMR) and in situ hybridization plus autoradiography in a novel examination of different phenotypes of adult myogenesis that arise from genetic disruptions in mice. Study of muscle extracts from normal and dystrophin-deficient mdx limb and diaphragm muscles confirmed our previous findings linking taurine and muscle regeneration at the peak of damage and repair. 1H-NMR distinguished biochemical differences in regenerating muscles that were consistent with the extent of repair in three strains: mdx dystrophic mice; MyoD(-/-) mice that lack expression of the early myogenic regulatory gene MyoD; and a double-mutant mdx:MyoD(-/-) strain lacking expression of both MyoD and dystrophin. We tested the hypothesis that differences in spectra according to genotype and the regeneration phenotype are related specifically to proliferation by committed myogenic precursor cells. 1H-NMR distinguished the three mutant strains: Taurine was highest in mdx muscles, with the phenotype of most effective regeneration; lowest in MyoD(-/-) muscles, with the least effective formation of new muscle in repair, as reported previously; and intermediate in double-mutant muscles, now reported to show an intermediate repair phenotype. The early and late muscle precursors (mpcs) expressing myf5 and myogenin were examined for proliferation. Eighteen percent of mdx myf5-positive mpcs were proliferative, whereas myf5-positive mpcs did not proliferate in regenerating muscles that lacked MyoD expression. By contrast, whereas 30% of myogenin-positive mpcs were proliferative in mdx muscles, almost none were proliferative in MyoD(-/-) muscles, and 12% were proliferative in double-mutant muscles. Therefore, the extent of accumulated structural regeneration, taurine levels, and proliferation of late mpc (expressing myogenin) were congruent across genotypes. Proliferation by early mpc (expressing myf5) was inhibited by the lack of MyoD expression during muscle regeneration. These studies indicate the potential for 1H-NMR monitoring of muscle status in disease, regeneration, and treatment.
Anat Rec 1998 10
PMID:Regeneration and myogenic cell proliferation correlate with taurine levels in dystrophin- and MyoD-deficient muscles. 977 86

Magnetic resonance (MR; synonymous with NMR = nuclear magnetic resonance) is a universal physical technique best known for non-invasive detection and anatomical mapping of water protons (H). MR-spectroscopy (MRS) records protons from tissue chemicals other than water, intrinsic phosphorus containing metabolites, sodium, potassium, carbon, nitrogen, and fluorine. MRS is therefore an imaging technique with the potential to record human and animal biochemistry in vivo. As a result of wide availability of MRI equipment in research laboratories and hospitals, MRS is a serious competitor with PET to define normal body composition and its perturbation by pharmacological and pathological events. This article describes practical aspects of in vivo MRS with particular emphasis on the brain, where novel metabolites have been described. A survey of these new aspects of neurochemistry emphasize their practical utility as neuronal and axonal markers, measures of energy status, membrane constituents, and osmolytes, as well as some xenobiotics, such as alcohol. The concept of multinuclear in vivo MRS is illustrated by diagnosis and therapeutic monitoring of several human brain disorders. Although these methods are currently most frequently encountered in human studies, as well as with transgenic and knockout mouse models, MRS adds a new dimension to anatomic and histopathologic descriptions.
Anat Rec 2001 04
PMID:Magnetic resonance spectroscopy of the human brain. 1132 70

Asymmetric addition of dialkylzincs to aldehydes in the presence of (2S)-3-exo-(dimethylamino)isoborneol [(S)-DAIB] exhibits various nonclassical phenomena. The enantiomeric excess (ee) of the alkylation product, obtained with partially resolved DAIB, is much higher than that of the chiral amino alcohol, while the rate decreases considerably as the ee of DAIB is lowered. The asymmetric amplification effects reflect the relative turnover numbers of two enantiomorphic catalytic cycles, where an essential feature is the reversible homochiral and heterochiral dimerization of the coexisting enantiomeric DAIB-based Zn catalysts. The interplay between the thermodynamics of the monomer/dimer equilibration and the kinetics of alkylation reaction strongly affect the overall profile of asymmetric catalysis. The self and nonself recognition of the chiral Zn catalysts is a general phenomenon when (S)-DAIB is mixed with its enantiomer, diastereomer, or even an achiral beta-amino alcohol. The degree of nonlinearity is highly affected not only by the structures and purity of catalysts but also by various reaction parameters. The salient features have been clarified on the basis of molecular weight measurements, NMR and X-ray crystallographic studies of organozinc complexes, and kinetic experiments, as well as computer-aided quantitative analysis.
Chem Rec 2001
PMID:Self and nonself recognition of chiral catalysts: the origin of nonlinear effects in the amino-alcohol catalyzed asymmetric addition of diorganozincs to aldehydes. 1189 67

The structural designation A originally made by Sharma and Alam to sclerophytin A was considered to be ambiguous and so notably strained relative to B that the latter was targeted for de novo synthesis (Scheme 1). Our two successful routes began with (5S)-(d-menthyloxy)-2(5H)-furanone and involved the application of cycloaddition, Claisen ring expansion, transannular oxymercuration, and 1,2-carbonyl transposition tactics to arrive at B. It was immediately apparent from polarity considerations and spectroscopic data that the antileukemic marine metabolite in question was in need of more deep-seated structural revision. Following close re-examination of an acquired authentic sample by advanced NMR techniques, the strong inference was made that sclerophytin A actually lacked a second oxygen bridge and was in reality the triol C. This conclusion was unequivocally confirmed by diverting an advanced intermediate generated earlier into a short sequence beginning with regiocontrolled dihydroxylation and terminating with configurational inversion at the secondary carbinol center. The status of other members of this series is also presented.
Chem Rec 2001
PMID:The sclerophytin A adventure. 1189 71

Studies on ciguatera fish poisoning led to clarification of the absolute stereochemistry of ciguatoxin, gambierol, gambieric acids, and maitotoxin. Anisotropic NMR reagents and fluorometric chiral HPLC reagents were effectively used together with synthesis of partial structures. Structures of 16 ciguatoxin congeners were successfully elucidated by FAB/MS/MS using samples of 5 microg or less. Stereochemical assignments were also achieved on dinophysistoxin-1, pectenotoxins, yessotoxins, polycavernoside-A, azaspiracid, and prymnesins. The toxins possessed poly-cyclic-ether structures and originated from unicellular algae. Biological functions are briefly described.
Chem Rec 2001
PMID:The chemistry and biological function of natural marine toxins. 1189 21

Recent studies of the synthesis, structures, spectroscopic properties, and reactions of a series of isolable metallylenes (R2E:, E = Si (1), Ge (2), and Sn (3); R2 = 1,1,4,4-tetrakis(trimethylsilyl)butane-1,4-diyl) are summarized. Because these group-14 metallylenes bear the same helmet-like ligand, a straightforward discussion of the element-dependence of the intrinsic properties of the group-14 element divalent compounds is possible. All these metallylenes were monomeric both in solution and in the solid state, indicating the effective steric protection by the ligand against dimerization. A small sigma-pi conjugation between C-Si(substituent) sigma orbitals and the vacant npz orbitals of divalent atoms in R2E: exists and the extent decreases in the order E = Si > Ge > Sn, as evidenced by UV-vis and NMR spectroscopies and X-ray crystallography. However, the extent of the sigma-pi conjugation in metallylenes 1-3 was much smaller than the electron-donating effects of neighboring nitrogen atoms in known stable cyclic diamino-substituted metallylenes, and hence metallylenes 1-3 are regarded as the least electronically perturbed. Comparative studies of the unique reactions among these metallylenes are also discussed.
Chem Rec 2004
PMID:Comparative chemistry of isolable divalent compounds of silicon, germanium, and tin. 1534 Sep 9


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