| 1. |
- Ding, HT, et al.
(författare)
-
Parallel cloning, expression, purification and crystallization of human proteins for structural genomics
- 2002
-
Ingår i: Acta Crystallographica. Section D: Biological Crystallography. - 1399-0047. ; 58, s. 2102-2108
-
Tidskriftsartikel (refereegranskat)abstract
- 54 human genes were selected as test targets for parallel cloning, expression, purification and crystallization. Proteins from these genes were selected to have a molecular weight of between 14 and 50 kDa, not to have a high percentage of hydrophobic residues (i.e. more likely to be soluble) and to have no known crystal structures and were not known to be subunits of heterocomplexes. Four proteins containing transmembrane regions were selected for comparative tests. To date, 44 expression clones have been constructed with the Gateway(TM) cloning system (Invitrogen, The Netherlands). Of these, 35 clones were expressed as recombinant proteins in Escherichia coli strain BL21 (DE3)-pLysS, of which 12 were soluble and four have been purified to homogeneity. Crystallization conditions were screened for the purified proteins in 96-well plates under oil. After further refinement with the same device or by the hanging-drop method, crystals were grown, with needle, plate and prism shapes. A 2.12 Angstrom data set was collected for protein NCC27. The results provide insights into the high-throughput target selection, cloning, expression and crystallization of human genomic proteins.
|
|
| 2. |
- Scherer, SW, et al.
(författare)
-
Human chromosome 7: DNA sequence and biology
- 2003
-
Ingår i: Science (New York, N.Y.). - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 300:5620, s. 767-772
-
Tidskriftsartikel (refereegranskat)abstract
- DNA sequence and annotation of the entire human chromosome 7, encompassing nearly 158 million nucleotides of DNA and 1917 gene structures, are presented. To generate a higher order description, additional structural features such as imprinted genes, fragile sites, and segmental duplications were integrated at the level of the DNA sequence with medical genetic data, including 440 chromosome rearrangement breakpoints associated with disease. This approach enabled the discovery of candidate genes for developmental diseases including autism.
|
|
| 3. |
- Li, H. Y., et al.
(författare)
-
Properties of a dinuclear Mn(III,III) complex with a tri-phenolate ligand N4O3 (3-) and a new complex containing a ligand covalently linked to ruthenium tris-bipyridine
- 2004
-
Ingår i: Huaxue xuebao. - 0567-7351. ; 62:9, s. 916-922
-
Tidskriftsartikel (refereegranskat)abstract
- A new high valent complex [Mn-2(III, III)L(mu-OAc)(2)].PF6 (2a) was prepared, where L was the trianion of 2, 6-bis {[(2-hydroxy-5-tert-butylbenzyl) (pyridyl-2-methyl)-amino]-methyl}-4-methylphenol, which contains two additional phenolate groups and two tert-butyl groups compared to its parent [Mn-2(II, II)(bpmp)(mu-OAc)(2)].ClO4 (1). These improvements narrowed the disparity between the new model and (Mn)(4) cluster (OEC in nature). Moreover, L was modified to be covalently linked with Ru(II) tris-bipyridine through an amide bond to construct a complex 2b for the study of photoinduced electron transfer (PET). UV-vis, IR, emission spectra and electrochemistry were used to investigate their photochemistry properties. The results showed that 2b has good photochemistry properties and the E-1/2 of Ru3+/Ru2+ was higher than those of phenol(+)/phenol and Mn(III, IV)/Mn(III, III). After coordination of manganese ions, the electron transfer process in the model complex conforms to the basic principles of electron donor side of photosystem II (PS II) in nature.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Shi, F., et al.
(författare)
-
Synthesis and properties of a new donor model compound for PSII
- 2004
-
Ingår i: Gaodeng xuéxiào huàxué xuébào. - 0251-0790. ; 25:9, s. 1666-1672
-
Tidskriftsartikel (refereegranskat)abstract
- As a model compound for redox components on the donor side of photosystem II (PS II) in green plants, a supramolecular complex 2 was synthesized and characterized. In this complex, two {[(2-hydroxy-3-(morpholin-4-ylmethyl)-5-tert-butyl-benzyl)(pyridyl-2-methyl)amino]methyl} arms are linked to the ortho-positions of a phenol which is expected covalently to be linked to Ru(II) tris-bipyridine through an amide bond. The arms on the substituted-phenol can coordinate two Mn(III) ions. The structure of complex 2 was confirmed by electrospray ionization mass spectrometry (ESI-MS) and 2D-NMR (gCOSY, HSQC and HMBC). Its photochemical and electrochemical properties were studied. The results showed that the MLCT band of the compound was red-shifted compared to that of [Ru(byp)(3)](2+) and the luminescence quantum yield was enhanced. In addition, the oxidation potential of ruthenium was higher than the phenol(+)/phenol and Mn(III, IV)/Mn(III) which was consisted with the electron transfer sequence of the donor side of PS II in nature. All these showed that this compound was a good model to mimic the donor side of PS II.
|
|
| 7. |
- Shi, F., et al.
(författare)
-
Synthesis and spectral properties of a new ruthenium(II) tris-bipyridine with four ester groups and substituted phenol
- 2004
-
Ingår i: Huaxue xuebao. - 0567-7351. ; 62:7, s. 713-719
-
Tidskriftsartikel (refereegranskat)abstract
- A new ruthenium(II) complex (1) with four ester groups have been designed and synthesized, in which a phenol substituted by {[(2-hydroxy-3-(morpholin-4-ylmethyl)-5-tent-butylbenzyl) (pyridyl-2-methyl) amino]methyl} groups was covalently linked to ruthenium (II) tris-bipyridine. The structure of complex 1 was characterized by electrospray ionization mass spectrometer (ESI-MS) and 1D-NMR, 2D-NMR (gCOSY, HSQC and HMBC) spectra. The electrochemical and spectral properties were also studied. Introduction of the four carboxyl acid groups and the donor ligand tuned the spectra and the redox properties of compound 1. The MLCT transition was turned from 451 to 474 nm and the complex had long lifetime of the (MLCT)-M-3 state emission. Moreover, the oxidation potential of Ru3+/Ru2 + of compound 1 was similar to 360 mV higher than that of [Ru(bpy)(3)](2+) which would enhance the driving-force of electron transfer. These results showed that the compound 1 had proper redox potentials and was suitable for being used as photosensitizer of solar cell.
|
|
| 8. |
- Zhang, L., et al.
(författare)
-
Transition from triple helix to coil of Lentinan in solution measured by SEC, viscometry, and C-13 NMR
- 2002
-
Ingår i: Polymer journal. - : Springer Science and Business Media LLC. - 0032-3896 .- 1349-0540. ; 34:6, s. 443-449
-
Tidskriftsartikel (refereegranskat)abstract
- Lentinan, beta-(1 --> 3)-D-glucan with (1 --> 6) branching, was isolated from Lentinus edodes. Weight-average molecular weight M-w radius of gyration < s(2) > (1/2) and intrinsic viscosity [eta] of Lentinan in 0.2 M NaCl aqueous solution, dimethylsulfoxide (DMSO) and water/DMSO mixtures were measured by light scattering (LS), size exclusion chromatography (SEC) combined with LS, and viscometry. The results indicated that the glucan exists mainly as triple-helical chains in 0.2 M NaCl aqueous solution and water/DMSO mixtures with over 20 wt% water content, and as single-flexible chain in DMSO. The data from SEC-LS, viscosity and C-13 NMR measurements proved strongly that the helix-coil conformation transition occurred in a narrow range from 80 to 85 wt% DMSO aqueous solution, accompanying with obvious changes of M-w, < s(2) >(1/2)(z), [eta] as well as signals of C6 and C6(s). The transition of Lentinan in water/DMSO mixture was irreversible. The difference in C-13 NMR spectra for the triple-helical and coil conformations was the disappearance of the signals of C3 in beta-(1 --> 3)- linked backbone and the enhancement in relative intensities of glucose substituted C6s in the helix state, as well as the appearance of an asymmetric and broad peak of C6 in the intermediate of the conformation change. This suggests that the immobilization of the backbone by binding with intra and intermolecular hydrogen bonds resulted in the loss of the signals of its carbon atoms in the triple helix state. An overcoating cylinder model composed of the beta-(1 --> 3)- linked backbone as helix core and the side chains as rotatable overcoat was proposed to illustrate the triple-helical conformation and its transition in the solution.
|
|
