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PLoS One ; 15(9): e0238179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881902


Carotenoid cleavage dioxygenase (CCD), a key enzyme in carotenoid metabolism, cleaves carotenoids to form apo-carotenoids, which play a major role in plant growth and stress responses. CCD genes had not previously been systematically characterized in Brassica napus (rapeseed), an important oil crop worldwide. In this study, we identified 30 BnCCD genes and classified them into nine subgroups based on a phylogenetic analysis. We identified the chromosomal locations, gene structures, and cis-promoter elements of each of these genes and performed a selection pressure analysis to identify residues under selection. Furthermore, we determined the subcellular localization, physicochemical properties, and conserved protein motifs of the encoded proteins. All the CCD proteins contained a retinal pigment epithelial membrane protein (RPE65) domain. qRT-PCR analysis of expression of 20 representative BnCCD genes in 16 tissues of the B. napus cultivar Zhong Shuang 11 ('ZS11') revealed that members of the BnCCD gene family possess a broad range of expression patterns. This work lays the foundation for functional studies of the BnCCD gene family.

Brassica napus/enzimologia , Dioxigenases/genética , Genoma de Planta , Proteínas de Plantas/genética , Arabidopsis/enzimologia , Brassica napus/genética , Carotenoides/metabolismo , Mapeamento Cromossômico , Dioxigenases/classificação , Dioxigenases/metabolismo , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 7): o1695-6, 2009 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-21582950


The crystal of the title Schiff base compound, C(20)H(18)ClN(3)O(3)·H(2)O, was twinned by a twofold rotation about (100). The asymmetric unit contains two crystallographically independent mol-ecules with similar conformations, and two water mol-ecules. The C=N-N angles of 115.7 (6) and 116.2 (6)° are significantly smaller than the ideal value of 120° expected for sp(2)-hybridized N atoms and the dihedral angles between the benzene ring and quinoline ring system in the two mol-ecules are 52.5 (7) and 53.9 (7)°. The mol-ecules aggregate via C-Cl⋯π and π-π inter-actions [centroid-centroid distances = 3.696 (5)-3.892 (5) Å] and weak C-H⋯O inter-actions as parallel sheets, which are further linked by water mol-ecules through N-H⋯O and O-H⋯O hydrogen bonds into a supra-molecular two-dimensional network.

Anal Biochem ; 380(2): 223-8, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18598667


In sodium acetate-acetic acid buffer solution, Au, Ag, Pt, Pd, Fe3O4, and Cu2O nanoparticles have catalytic enhancement effect on the reduction of Cu2+ by ascorbic acid to form large copper particles that exhibit a strong resonance scattering peak at 610 nm. Those nanocatalytic reactions were studied by the resonance scattering spectral technique, and smaller nanogold exhibited stronger catalytic enhancement effect in pH 4.2 sodium acetate-acetic acid buffer solution. The resonance scattering intensity at 610 nm increased linearly with the concentrations of 0.02 to 1.60, 0.040 to 1.20, and 0.12 to 4.70 nM nanogold in sizes of 5, 10, and 15 nm with detection limits of 0.010, 0.030, and 0.10 nM, respectively. An immunonanogold-catalytic resonance scattering bioassay was established, combining the immunonanogold-catalytic effect on CuSO4-ascorbic acid reaction with the resonance scattering detection technique. As a model, 0.03 to 7.5 ng ml(-1) immunoglobulin G can be assayed by this immunonanogold-catalytic resonance scattering bioassay with a detection limit of 0.015 ng ml(-1).

Ácido Ascórbico/química , Cobre/química , Imunoglobulina G/análise , Imuno-Histoquímica/métodos , Nanopartículas Metálicas/química , Catálise , Cátions Bivalentes/química , Sulfato de Cobre/química , Fluorometria/métodos , Ouro/química , Humanos , Espectroscopia de Ressonância Magnética/métodos , Oxirredução , Fenantrolinas/química
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(12): 2935-8, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19248517


Gold nanoparticles the size of about 10 nm were prepared by improved trisodium citrate reduction procedure, and were used to label goat anti-human IgG to obtain a sensitive spectral probe for IgG in the condition of pH 6.5. The immune reaction of nanogold-labeled IgG antibody (anti-IgG) with the antigen IgG took place to form the nanogold immune complex in pH 7.O Na2HPO4-C6H8O7 buffer solution and in the presence of polyethylene (PEG). The optimal immunoreaction conditions were pH 7.0, 10.76 microg x mL(-1) nanogold-labeled anti-IgG, 8.0% PEG 6000 and incubation time of 30 min under the ultrasonic irradiation. After centrifuging for 15 min at 16000 rpm, the excess nanogold-labeled anti-IgG in the upper solutions was obtained, and was used to catalyze the colored particle reaction of HAuCl4 with NH2 OH x HCl to produce gold particles with bigger size. The influence of pH value, HAuCl4 and NH2OH x HCl concentration, and reaction temperature and time on the immunonanogold catalytic reaction was considered spectrophotometrically. A pH 2.27 Na3C6H5O7-HCl buffer solution, 0.094 mmol x L HAuCl4, 1.92 mmol x L NH22OH x HCl, and reaction time of 6 min at 30 degrees C water bath were chosen for use. Results demonstrated that with increasing IgG, the concentration of gold labeled anti-IgG in the upper solution decreased, and the absorbance decreased linearly. Linear relationships between the decreased absorbance at 700 nm and the IgG concentration CIgG in the range of 0.10-10 ng x mL(-1) were obtained. Its regress equation was deltaA(760 nm) = 0.0144c(IgG) + 0.0042, the related coefficient was 0.9926, and the detection limit reached 0.06 ng x mL(-1) IgG. The influence of foreign substances on the determination of 3 ng x mL(-1) IgG was examined, with the relative error +/-10%. Results showed that the following coexistent substances had no impact on the assay: 6000 ng x mL(-1) HSA, 6000 ng x mL(-1) gluocose, 6000 ng x ml(-1) Zn(II), 3000 ng x mL(-1) IgA, 3000 ng x mL(-1) Ca(II), 3000 ng x mL(-1) L-arginine, 3000 ng x mL(-1) beta-phenylalanine, 2400 ng x mL(-1) Cu(II), 2400 ng x mL(-1) EDTA, 2400 ng x mL(-1) L-cystinol etc. This showed that the assay has high selectivity. The sensitive, rapid and highly specific assay was applied to the quantification of IgG in human sera, with satisfactory results.

Ouro/química , Imunoglobulina G/química , Nanopartículas Metálicas/química , Espectrofotometria/métodos , Animais , Anticorpos Anti-Idiotípicos/imunologia , Catálise , Humanos , Imunoglobulina G/imunologia
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): o194-5, 2008 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21581649


The title compound, C(16)H(12)N(2)O(6)·2C(3)H(7)NO, lies across a crystallographic inversion centre which is situated at the midpoint of the central N-N bond. The substitution at the C=N bond adopts a trans configuration and it is essentially coplanar with the benzene ring [N-C-C-C torsion angles = -173.9 (4) and 6.4 (6)°]. All torsion angles involving non-H atoms are close to 180°. Intra-molecular O-H⋯O and weak C-H⋯O hydrogen bonds form S(6) and S(5) ring motifs, respectively, while inter-molecular O-H⋯O and weak C-H⋯O hydrogen bonds connect the Schiff base mol-ecule to solvent dimethyl-formamide mol-ecules.