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Mahmoudkhani AH, Langer V, Lindqvist O. Radical Addition of Bis(Trimethylsilyl)Phosphonate to Vinyltrimethylsilane: Crystal Structure of (2-Trimethylsilylethyl)Phosphonic Acid. PHOSPHORUS SULFUR 1999. [DOI: 10.1080/10426509908053596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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152
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Vosegaard T, Hald E, Langer V, Skov HJ, Daugaard P, Bildsoe H, Jakobsen HJ. Improved hardware and software for single-crystal NMR spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1998; 135:126-132. [PMID: 9799686 DOI: 10.1006/jmre.1998.1551] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Design of state-of-the-art instrumentation and software for acquisition and analysis of single-crystal NMR spectra is presented. The design involves highly accurate rotation of a goniometer, and the acquisition of all the spectra for each rotation axis is automatically controlled by the host computer of the spectrometer using a homebuilt interface between the computer and the single-crystal probe. Moreover, a software package (ASICS) for fast and routine assignment/analysis of complex single-crystal spectra has been developed. Employing this equipment, the acquisition and complete analysis of single-crystal NMR spectra may be performed in about the same time as required for powder methods (spinning or static). The hardware and software are compared to recent alternative approaches within single-crystal NMR. Finally, it has been observed that single-crystal NMR techniques may provide the desired data for samples where powder methods fail.
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153
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Steiner B, Koós M, Langer V, Gyepesova D, Smrčok L. 4-Amino-4-cyano-4,6-dideoxy sugar derivatives from methyl 6-deoxy-2,3-O-isopropylidene-α-l-lyxo-hexopyranosid-4-ulose via Strecker-type reaction. Carbohydr Res 1998. [DOI: 10.1016/s0008-6215(98)00173-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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154
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Langer V, Becker HC. Crystal structure of 2,7-diazapyrene,C14H8N2. Z KRIST-NEW CRYST ST 1997. [DOI: 10.1524/ncrs.1997.212.1.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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155
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Karlsson BG, Tsai LC, Nar H, Sanders-Loehr J, Bonander N, Langer V, Sjölin L. X-ray structure determination and characterization of the Pseudomonas aeruginosa azurin mutant Met121Glu. Biochemistry 1997; 36:4089-95. [PMID: 9100002 DOI: 10.1021/bi962416o] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The Met121Glu azurin mutant has been crystallized and the structure determined at a resolution of 2.3 A. In the crystal structure a carboxyl oxygen of Met121Glu is coordinated to the metal at a distance of 2.2 A. Single-crystal resonance Raman spectroscopy was used to show that the glutamic acid residue in the copper site was in the protonated state. Titration of this residue gives rise to a number of unusual, pH-dependent properties: as the pH is increased from 4 to 8, the S(Cys)-Cu ligand-to-metal charge transfer bands are blue shifted and their intensity ratio is reversed, the EPR signal changes from type 1 copper to a new form of protein-bound copper, and the redox potential changes from 370 to 180 mV. The spectroscopic changes in this pH interval are consistent with a two-state model. From the pH dependence of the optical and EPR spectra, pKa = 5.0 for the glutamic acid in the oxidized protein was determined.
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156
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Bonander N, Vänngård T, Tsai LC, Langer V, Nar H, Sjölin L. The metal site of Pseudomonas aeruginosa azurin, revealed by a crystal structure determination of the Co(II) derivative and Co-EPR spectroscopy. Proteins 1997; 27:385-94. [PMID: 9094740 DOI: 10.1002/(sici)1097-0134(199703)27:3<385::aid-prot6>3.0.co;2-c] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The crystal structure of cobalt-substituted azurin from Pseudomonas aeruginosa has been determined to final crystallographic R value of 0.175 at 1.9 A resolution. There are four molecules in the asymmetric unit in the structure, and these four molecules are packed as a dimer of dimers. The dimer packing is very similar to that of the wild-type Pseudomonas aeruginosa azurin dimer. Replacement of the native copper by the cobalt ion has only small effects on the metal binding site presumably because of the existence of an extensive network of hydrogen bonds in its immediate neighborhood. Some differences are obvious, however. In wild-type azurin the copper atom occupies a distorted trigonal bipyramidal site, while cobalt similar to zinc and nickel occupy a distorted tetrahedral site, in which the distance to the Met121,S(delta) atom is increased to 3.3-3.5 A and the distance to the carbonyl oxygen of Gly45 has decreased to 2.1-2.4 A. The X-band EPR spectrum of the high-spin Co(II) in azurin is well resolved (apparent g values gx' = 5.23; gy' = 3.83; gz' = 1.995, and hyperfine splittings Ax' = 31; Ay' = 20-30; Az' = 53 G) and indicates that the ligand field is close to axial.
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157
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Tsai LC, Bonander N, Harata K, Karlsson G, Vänngård T, Langer V, Sjölin L. Mutant Met121Ala ofPseudomonas aeruginosaAzurin and Its Azide Derivative: Crystal Structures and Spectral Properties. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 1996; 52:950-8. [PMID: 15299604 DOI: 10.1107/s0907444996004982] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The crystal structures of the azurin mutant Met121Ala and its azide derivative Met121Ala-azide from Pseudomonas aeruginosa have been determined. The final crystallographic R values are 21.3 and 19.4% for the two structures, respectively. In the Met121Ala mutant, the distance between the copper ion and His117 increases by 0.34 A compared with the wild-type structure. The removal of the methionine in the apical position induces a shortening of the distance from the copper ion to the carbonyl O atom of Gly45 from 2.97 to 2.74 A. In the Met121Ala-azide structure, the azide anion occupies the cavity created by replacing the Met121 side chain with the smaller methyl group of Ala. The azide anion binds with a terminal N atom to the copper ion at a distance of about 2.04 A. In addition, the copper ion has moved out of the trigonal plane by about 0.26 A towards the azide anion. Thus, the copper site in this structure has a distorted tetrahedral arrangement. The spectroscopic characteristics show, in addition, that the copper sites in the two structures are distinctively different. The Met121Ala mutant still maintains the properties of an ordinary type 1 copper site while the Met121Ala-azide derivative has an absorption maximum at about 409 nm and the copper hyperfine coupling has increased to a value intermediate between those of type 2 copper and the wild-type azurin.
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158
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Smrčina M, Vyskočil Š, Hanuš V, Polášek M, Langer V, Chew BGM, Zax DB, Verrier H, Harper K, Claxton TA, Kočovský P. The SN2 Reaction in the Solid State. An Unusual, BAl2 Aminolysis of an Ester Group in Crystalline (±)-2-Amino-2‘-hydroxy-3‘-(methoxycarbonyl)- 1,1‘-binaphthyl Elucidated by X-ray Diffraction and Isotopic Labeling. New Experimental Evidence for Linearity in SN2 Substitution. J Am Chem Soc 1996. [DOI: 10.1021/ja951920y] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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159
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Fogel NY, Buchstab EI, Pokhila AS, Erenburg AI, Langer V. Disorder and superconductivity in Mo/Si multilayers. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:71-74. [PMID: 9981944 DOI: 10.1103/physrevb.53.71] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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160
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Tsai LC, Sjölin L, Langer V, Bonander N, Karlsson BG, Vänngård T, Hammann C, Nar H. Structure of the azurin mutant nickel–Trp48Met fromPseudomonas aeruginosaat 2.2 Å resolution. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 1995; 51:711-7. [PMID: 15299800 DOI: 10.1107/s0907444995001041] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The structure of the azurin mutant nickel-Trp48Met from Pseudomonas aeruginosa has been determined by difference Fourier synthesis using phases from the wild-type azurin model. The final crystallographic R value is 0.170 for 17 394 reflections to a resolution of 2.2 A. The mutant crystallized in the orthorhombic space group P2(1)2(1)2(1), a = 57.4, b = 80.4, c = 110.3 A. The four molecules in the asymmetric unit are packed as a dimer of dimers. The nickel metal site of this mutant structure is similar to the zinc metal site in the azurin Asp47 mutant. The site-specific mutation was performed at residue Trp48, which is located in the center of the protein in a highly hydrophobic environment, to investigate its suggested role in the long-range electron-transfer pathway between the disulfide bond on one side of the protein to the Cu centre. The structure around the mutation site Met48 showed no significant change compared with the wild-type structure.
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161
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Kozísek J, Ulický L, Floch L, Langer V. 1-(2-Benzothiazolyl)-3-methoxycarbonylmethyl-2-thioxo-4-imidazolidinone, C13H11N3O3S2. Acta Crystallogr C 1995. [DOI: 10.1107/s0108270195000254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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162
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Lyngfelt A, Langer V, Steenari BM, Puromäki K. Calcium sulphide formation in fluidized bed boilers. CAN J CHEM ENG 1995. [DOI: 10.1002/cjce.5450730209] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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163
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Nielsen NC, Daugaard P, Langer V, Thomsen JK, Nielsen S, Sørensen OW, Jakobsen HJ. A flat-coil NMR probe with hydration control of oriented phospholipid bilayer samples. JOURNAL OF BIOMOLECULAR NMR 1995; 5:311-314. [PMID: 22911503 DOI: 10.1007/bf00211758] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/1995] [Accepted: 03/08/1995] [Indexed: 06/01/2023]
Abstract
A novel flat-coil solid-state NMR probe capable of controlling the hydration of oriented phospholipid bilayers in the course of long-term experiments, is described. Perfect hydration control for at least five days of intense radio-frequency pulsing is demonstrated using (31)P NMR of oriented dimyristoylphospha-tidylcholine bilayers. The probe design will be of particular importance for studies of peptides and proteins oriented in lipid bilayers.
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164
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Langer V, Stolz V. Picosecond quantum-beat spectroscopy of quadrupole polaritons in Cu2O. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 51:2103-2114. [PMID: 9978954 DOI: 10.1103/physrevb.51.2103] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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165
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Strandberg H, Langer V, Johansson LG, Bálint J, Fogassy E, Christensen LK, Napoli A, Sindona G, Aksnes DW, Francis GW, Aaberg A. Structure of Cu2.5(OH)3SO4.2H2O: a Novel Corrosion Product of Copper. ACTA ACUST UNITED AC 1995. [DOI: 10.3891/acta.chem.scand.49-0005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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166
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Langer V, Becker HD. Crystal structure of (Ε) 1-(9-anthroyl)-1,2- di(9-anthryl)ethene, C 45H 28O. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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167
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Langer V, Becker HD. Crystal structure of head-to-tail 4π+4π photoadduct of 9-methoxyanthracene to 9-methoxy-10-methylanthracene, C 31H 26O 2. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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168
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Langer V, Becker HD. Crystal structure of head-to-tail 4π+4π ρhοtο-dimer of 9-methoxy-10-methylanthracene, C 32H 28O 2. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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169
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Langer V, Becker HD. Crystal structure of 9-(10-methoxy-9-anthryl)-10- [1-(9-anthryl)-1-methoxy-1,2-propandienylidene]-9,10-dihydroanthracene, C 46H 32O 2. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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170
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Langer V, Becker HD. Crystal structure of 4π+4π photocyclomer of (Ζ) 1-(9-anthryloxy)-1,2-di(9-anthryl)-2-methoxyethene, C 45H 30O 2. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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171
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Langer V, Becker HD. Crystal structure of rac 3-(9-anthryl)-1,2-epoxypropane, C 17H 14O. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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172
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Langer V, Becker HD. Crystal structure of 2-(9-anthryl)-2-propanol, C 17H 16O. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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173
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Langer V, Becker HD. Crystal structure of 1,4-bis[β(9-anthryl)ethyloxycarbonyl]piperazine dichloromethane solvate, (C 38H 34N 2O 4)(CH 2Cl 2 ). Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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174
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Langer V, Becker HD. Crystal structure of 1-[β(9-anthryl)ethyloxycarbonyl]-4-phenylpiperazine, C 27H 26N 2O 2. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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175
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Langer V, Becker HD. Crystal structure of 5-cholesten-3β-yl (αS)-α-methyl-β-(9-anthryl)ethyl carbonate, C 45H 60O 3. Z KRIST-CRYST MATER 1993. [DOI: 10.1524/zkri.1993.207.12.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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