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Petersen EN, Jensen LH, Honoré T, Braestrup C, Kehr W, Stephens DN, Wachtel H, Seidelman D, Schmiechen R. ZK 91296, a partial agonist at benzodiazepine receptors. Psychopharmacology (Berl) 1984; 83:240-8. [PMID: 6089246 DOI: 10.1007/bf00464788] [Citation(s) in RCA: 96] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
5-benzyloxy-4-methoxymethyl-beta-carboline-3-carboxylate) is a potent and selective ligand for benzodiazepine (BZ) receptors. Biochemical investigations indicate that ZK 91296 may be a partial agonist at BZ receptors. Such partial agonism may explain to some extent why ZK 91296 needs higher BZ receptor occupancy than diazepam for the same effect against chemical convulsants and for behavioural effects. The lack of sedative effects, and the very potent inhibition of reflex epilepsy, spontaneous epilepsy and DMCM-induced seizures suggest, furthermore, that ZK 91296 may possess pharmacological selectivity for a particular type of BZ receptor interaction, perhaps including topographic as well as receptor subtype differentiation.
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Braestrup C, Nielsen M, Honoré T, Jensen LH, Petersen EN. Benzodiazepine receptor ligands with positive and negative efficacy. Neuropharmacology 1983; 22:1451-7. [PMID: 6322039 DOI: 10.1016/0028-3908(83)90113-2] [Citation(s) in RCA: 212] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Recent studies have shown that benzodiazepine receptors can be affected not only by benzodiazepine agonists and antagonists but also by a new class of ligands which produce effects opposite to those of benzodiazepines, that is they produce convulsions and anxiety. These ligands can be described as having a negative efficacy at the receptor; tentatively they are named "inverse agonists". Pharmacological experiments indicate that agonists, antagonists and inverse agonists comprise a whole continuum of agents with a graduated variety of efficacy at the receptor. Biochemical studies, supported by published electrophysiological data, indicate that the benzodiazepine receptor allosterically up- or down-regulates the gain in the GABAergic system depending on the nature of the ligand.
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153
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Sieker LC, Jensen LH, Prickril BC, LeGall J. Crystallographic study of rubredoxin from the bacterium Desulfovibrio desulfuricans strain 27774. J Mol Biol 1983; 171:101-3. [PMID: 6644818 DOI: 10.1016/s0022-2836(83)80316-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Rubredoxin from Desulfovibrio desulfuricans (strain 27774) has been isolated and crystallized. Preliminary amino acid and crystallographic analyses indicate that this rubredoxin is the smallest rubredoxin isolated so far. The amino acid analysis indicates that the molecule is composed of 45 to 48 residues and contains histidine, which is unusual for rubredoxins from anaerobic bacteria. The X-ray diffraction pattern from these crystals reveals they belong to space group P1 with cell parameters: a = 24.92 A, b = 17.79 A, c = 19.72 A, alpha = 101.0 degrees, beta = 83.4 degrees, gamma = 104.5 degrees. The unit cell volume of 8283 A3 indicates a molecule with molecular weight no greater than 5500 and is consistent with the smaller number of amino acids found in this rubredoxin. The solvent content of this rubredoxin crystal appears to be the lowest observed in crystalline proteins.
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154
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Jensen LH, Petersen EN. Bidirectional effects of benzodiazepine receptor ligands against picrotoxin- and pentylenetetrazol-induced seizures. J Neural Transm (Vienna) 1983; 58:183-91. [PMID: 6319592 DOI: 10.1007/bf01252804] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The dose response curves of picrotoxin-induced seizures and pentylenetetrazol-induced seizures were shifted to the right by the benzodiazepine (BZ) receptor agonist lorazepam, and to the left by the inverse agonists, DMCM, ZK 90886, FG 7142 and CGS 8216. The BZ receptor antagonists ZK 93426 and Ro 15-1788 had no effect on the dose response curves. The anticonvulsive action of lorazepam and the proconvulsive action of DMCM against picrotoxin-induced seizures and against pentylenetetrazol-induced seizures was inhibited by low doses of ZK 93426 and Ro 15-1788. These results indicate that the bidirectional effects of benzodiazepine receptor ligands on picrotoxin and pentylenetetrazol induced seizures is actually mediated through benzodiazepine receptors.
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Jensen LH, Petersen EN, Braestrup C. Audiogenic seizures in DBA/2 mice discriminate sensitively between low efficacy benzodiazepine receptor agonists and inverse agonists. Life Sci 1983; 33:393-9. [PMID: 6308372 DOI: 10.1016/s0024-3205(83)80014-9] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In experiments with audiogenic seizures in DBA/2 mice, we observed that several socalled benzodiazepine receptor antagonists exhibited either anticonvulsive (Ro 15-1788, PrCC) or proconvulsive (FG 7142, beta-CCE, CGS 8216) effects at high receptor occupancy (17-85%), as compared to benzodiazepines and DMCM which had anticonvulsive and proconvulsive actions, respectively, at very low receptor occupancy (less than 10%). Sensitive distinction between benzodiazepine receptor ligands with low anticonvulsive efficacy (partial agonists) and ligands with low proconvulsive, and maybe anxiogenic, efficacy (partial inverse agonists) can thus be obtained in sound seizure susceptible mice.
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156
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Petersen EN, Jensen LH, Honoré T, Braestrup C. Differential pharmacological effects of benzodiazepine receptor inverse agonists. ADVANCES IN BIOCHEMICAL PSYCHOPHARMACOLOGY 1983; 38:57-64. [PMID: 6142608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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157
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Johansen J, Jensen LH, Holm C. Morphological and electrophysiological mapping of giant neurons in the suboesophageal ganglia of Helix pomatia. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1982; 71:283-91. [PMID: 6121652 DOI: 10.1016/0300-9629(82)90401-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
1. To reveal the morphology of the suboesophageal ganglia of Helix pomatia, the connective tissue was completely removed and the preparations stained whole-mount with methyl green-pyronin G to display the relative locations of the neurons. 2. Fifteen large cells which could be recognized as individuals in at least 75% of the preparations investigated, were morphologically identified by size, position and color. 3. The cells were electrophysiologically characterized with respect to spontaneous activity, synaptic input from peripheral nerves, and response to application of drugs (e.g. ACh, DA and 5-HT). 4. The peripheral axonal projections of eight of the major identified cells were investigated by intracellular CoCl2 injection and by cobalt backfilling of the peripheral nerves.
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158
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Sieker LC, Bolles L, Stenkamp RE, Jensen LH, Appleby CA. Preliminary X-ray study of a dimeric form of hemerythrin from Phascolosoma arcuatum. J Mol Biol 1981; 148:493-4. [PMID: 7310875 DOI: 10.1016/0022-2836(81)90189-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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159
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Sieker LC, Jensen LH, Bruschi M, LeGall J, Moura I, Xavier AV. Desulforedoxin: preliminary x-ray diffraction study of a new iron-containing protein. J Mol Biol 1980; 144:593-4. [PMID: 7253026 DOI: 10.1016/0022-2836(80)90340-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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160
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Watenpaugh KD, Sieker LC, Jensen LH. Crystallographic refinement of rubredoxin at 1 x 2 A degrees resolution. J Mol Biol 1980; 138:615-33. [PMID: 7411618 DOI: 10.1016/s0022-2836(80)80020-9] [Citation(s) in RCA: 156] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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161
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162
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Stenkamp RE, Sieker LC, Jensen LH. Crystallographic studies of azide, thiocyanate and perchlorate complexes of methemerythrin. J Mol Biol 1978; 126:457-66. [PMID: 218017 DOI: 10.1016/0022-2836(78)90052-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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163
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Jensen LH. Molecular anatomy: the role of X-ray structure analysis. Anat Rec (Hoboken) 1978; 192:97-100. [PMID: 707824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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164
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Adman ET, Stenkamp RE, Sieker LC, Jensen LH. A crystallographic model for azurin a 3 A resolution. J Mol Biol 1978; 123:35-47. [PMID: 98639 DOI: 10.1016/0022-2836(78)90375-3] [Citation(s) in RCA: 305] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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165
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Stenkamp RE, Sieker LC, Jensen LH, McQueen JE. Structure of methemerythrin at 2.8-Angstrom resolution: computer graphics fit of an averaged electron density map. Biochemistry 1978; 17:2499-504. [PMID: 678527 DOI: 10.1021/bi00606a007] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The crystal structure of methemerythrin from Themiste dyscritum has been determined at 2.8-Angstrom resolution by single isomorphous replacement technique combined with anomalous scattering from a K2HgI4 derivative. Noncrystallographic symmetry relating the four subunits in the asymmetric unit was used to obtain an average electron density map of the hemerythrin monomer, and a computer graphics system was used to fit a polypeptide model to the electron density. The average map was of sufficient quality to locate most of the amino acid side chains and to confirm the assignment of His-25, His-54, Glu-58, His-73, His-77, His-101, Asp-106, and Tyr-109 as the iron ligands. One of the mercury sites in the heavy atom derivative is located between two Cys-9 residues related by a noncrystallographic twofold axis, although no intersubunit disulfide bond is present in the native structure. The residues responsible for the binding of the subunits to form the octamer are identified.
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166
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Watenpaugh KD, Margulis TN, Sieker LC, Jensen LH. Water structure in a protein crystal: rubredoxin at 1.2 A resolution. J Mol Biol 1978; 122:175-90. [PMID: 682189 DOI: 10.1016/0022-2836(78)90034-7] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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167
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Adman ET, Sieker LC, Jensen LH, Bruschi M, Le Gall J. A structural model of rubredoxin from Desulfovibrio vulgaris at 2 A resolution. J Mol Biol 1977; 112:113-20. [PMID: 881725 DOI: 10.1016/s0022-2836(77)80159-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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168
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Pierrot M, Haser R, Frey M, Bruschi M, le Gall J, Sieker LC, Jensen LH. Some comparisons between two crystallized anaerobic bacterial ruberdoxins from Desulfovibrio gigas and D. vulgaris. J Mol Biol 1976; 107:179-82. [PMID: 1003467 DOI: 10.1016/s0022-2836(76)80026-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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169
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Adman ET, Siefker LC, Jensen LH. Structure of Peptococcus aerogenes ferredoxin. Refinement at 2 A resolution. J Biol Chem 1976; 251:3801-6. [PMID: 932007 DOI: 10.2210/pdb1fdx/pdb] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The model for ferredoxin from Peptococcus aerogenes, derived from a 2.8-A resolution map, has been refined with a 2-A resolution data set. The conventional index, R, decreased from 0.449 for the initial model to 0.188 for the unconstrained one and 0.206 for the constrained one. The standard deviations of the iron and sulfur atoms are 0.04 to 0.05 A and for the oxygen, nitrogen, and carbon atoms they range from 0.14 to 0.26 A. One hundred forty-six water oxygen atoms were included in the solvent part of the model and were checked by a highly selective criterion, suggesting that most of them represented water molecules.
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170
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Kurachi K, Sieker LC, Jensen LH. Structures of triclinic mono- and di-N-acetylglucosamine: lysozyme complexes--a crystallographic study. J Mol Biol 1976; 101:11-24. [PMID: 1255720 DOI: 10.1016/0022-2836(76)90063-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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171
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Stenkamp RE, Sieker LC, Jensen LH. Structure of the iron complex in methemerythrin. Proc Natl Acad Sci U S A 1976; 73:349-51. [PMID: 1061139 PMCID: PMC335905 DOI: 10.1073/pnas.73.2.349] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The coordination of the ligands about the iron atoms in methemerythrin from Themiste dyscritum has been deduced from a 2.8 A resolution electron density map. The complex can be described in terms of two trigonal antiprisms about the pair of iron atoms in each subunit, the antiprisms having one face in common. Ligands at eight of the nine coordination positions are protein side chains, the ninth presumably being water. Comparison of the electron density map for T. dyscritum methemerythrin with the sequence of Phascolopsis gouldii hemerythrin suggests six aromatic side chain ligands (five histidine and one tyrosine) and two nonaromatic side chain ligands. The latter provide atoms at two of the three vertices of the face shared by the two antiprisms, and these along with the presumed water at the third vertex form bridges between the iron atoms of each pair.
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172
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Sieker LC, Jensen LH, Samy TS. Neocarzinostatin: an antitumor protein a preliminary x-ray diffraction study. Biochem Biophys Res Commun 1976; 68:358-62. [PMID: 130133 DOI: 10.1016/0006-291x(76)91152-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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173
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174
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Adman E, Watenpaugh KD, Jensen LH. NH---S hydrogen bonds in Peptococcus aerogenes ferredoxin, Clostridium pasteurianum rubredoxin, and Chromatium high potential iron protein. Proc Natl Acad Sci U S A 1975; 72:4854-8. [PMID: 1061073 PMCID: PMC388830 DOI: 10.1073/pnas.72.12.4854] [Citation(s) in RCA: 227] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Results from refinement of the crystal structures of P. aerogenes ferredoxin and C. pasteurianum rubredoxin determined by x-ray diffraction show that there are 15-18 NH---S bonds in the former and six in the latter with lengths in the range 3.1-3.9 A. Earlier tritium exchange experiments are consistent with the presence of these hydrogen bonds in the ferredoxin structure and show that more peptide hydrogen atoms are available for exchange in apoferredoxin than in intact ferredoxin. Four types of NH---S bonds are observed and two of these are geometrically similar to the two types of 3(10) NH---O bonds. The existence of more NH---S bonds in ferredoxin than in high potential iron protein suggests why the -2 form of the Fe4S4 cluster is preferred in ferredoxin over the -1 form found in high potential iron protein. From comparison of Cys-X-Y-Cys sequences in rubredoxin, ferredoxin, and high potential iron protein we suggest that two Cys-X-Y-Cys-Z sequences, where Z may have conformation angles similar to glycine, are required to make a one-iron cluster, no more than one Cys-X-Y-Cys-Z-Gly sequence is required to form a Fe2S2 ferredoxin, and a Cys-X-Y-Cys-Gly sequence where Y has a conformation such that the cysteines bond to different iron atoms is necessary to form the tetrameric cluster.
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175
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Kurachi K, Sieker LC, Jensen LH. Metal ion binding in triclinic lysozyme. J Biol Chem 1975; 250:7663-7. [PMID: 240835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The binding sites of Mn2+, Co2+, and Gd3+ have been determined in triclinic lysozyme at pH 4.5 to 4.6. Mn2+ and Co2+ bind a site approximately 2.5 A from 1 of the oxygen atoms of the Glu-35 chain. The occupancy of the Mn2+ site is 0.22, corresponding to 1 bound ion for each 4.6 protein molecules. The occupancy of the Co2+ site is much lower, about 0.048. Gd3+ appears to be bound at two sites, the main one 2.5 A from an oxygen atom of the Glu-35 side chain, the other 3.1 A from an oxygen atom of the Asp-52 chain. The occupancy of both Gd3+ sites is low, 0.036 and 0.016, the latter being so low that the presence of the ion at this site is in doubt. The binding site of Mn2+ in the di(N-acetylglucosamine)-lysozyme complex has also been determined. It does not differ significantly from the Mn2+ binding site in the native protein, but the occupancy is lower, 0.16.
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176
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177
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Adman ET, Watenpaugh KD, Sieker LC, Jensen LH. Ilya Glezer's Struggle. Science 1975; 187:902-5. [PMID: 17745262 DOI: 10.1126/science.187.4180.902-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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178
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179
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Jensen LH. Protein model refinement based on x-ray data. ANNUAL REVIEW OF BIOPHYSICS AND BIOENGINEERING 1974; 3:81-93. [PMID: 4370908 DOI: 10.1146/annurev.bb.03.060174.000501] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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180
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181
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Watenpaugh KD, Sieker LC, Jensen LH. The binding of riboflavin-5'-phosphate in a flavoprotein: flavodoxin at 2.0-Angstrom resolution. Proc Natl Acad Sci U S A 1973; 70:3857-60. [PMID: 4521211 PMCID: PMC427344 DOI: 10.1073/pnas.70.12.3857] [Citation(s) in RCA: 127] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The crystal structure of the oxidized form of flavodoxin from Desulfovibrio vulgaris has been studied at 2.0-A resolution, and a detailed description of the region around the flavin mononucleotide binding site is now available. The flavin is between a tyrosine group, roughly parallel to it on one side, and a tryptophan, about 45 degrees from being parallel, on the other side. The two carbonyl groups and two nitrogen atoms of the flavin are hydrogen bonded to the peptide chain of the protein, while the two methyl groups are exposed at the surface of the protein. The phosphate group of the flavin mononucleotide is inside the protein and extensively hydrogen bonded to it. The ribityl group is hydrogen bonded both to the protein and to water on the surface of the protein.
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182
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183
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Adman ET, Sieker LC, Jensen LH. Structure of a bacterial ferredoxin. J Biol Chem 1973; 248:3987-96. [PMID: 4708097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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184
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Carter CW, Kraut J, Freer ST, Alden RA, Sieker LC, Adman E, Jensen LH. A comparison of Fe 4 S 4 clusters in high-potential iron protein and in ferredoxin. Proc Natl Acad Sci U S A 1972; 69:3526-9. [PMID: 4509310 PMCID: PMC389813 DOI: 10.1073/pnas.69.12.3526] [Citation(s) in RCA: 187] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The structures of both oxidized (HP(ox)) and reduced (HP(red)) high-potential iron protein and of oxidized ferredoxin (Fd(ox)) have been partially refined at 2.0-A resolution by methods similar to those applied to the protein rubredoxin [Watenpaugh, K. D., Sieker, L. C., Herriott, J. R. & Jensen, L. H. (1971) Cold Spring Harbor Symp. Quant. Biol. 36, 359-367]. Average bond lengths and angles in the HP(red) and Fd(ox) Fe(4)S(4) (*) clusters are the same to within the root-mean square (rms) deviation of each mean value. A preliminary comparison of the two HiPIP oxidation states indicates that the HP(ox) cluster is geometrically similar to the HP(red) cluster, but that it is smaller by 0.1-0.2 A in certain dimensions. The HiPIP and ferredoxin cluster geometry is also nearly identical to that reported recently for a synthetic analog [Herskovitz, T., Averill, B. A., Holm, R. A., Ibers, J. A., Phillips, W. D. & Weither, J. F. (1972) Proc. Nat. Acad. Sci. USA 69, 2437-2441]. An apparent paradox presented by the large difference between the HiPIP and ferredoxin electrode potentials can be resolved by the assumption that the Fe(4)S(4) (*) cluster has not two but three oxidation states. The fully oxidized (HP(ox)) and fully reduced (Fd(red)) clusters are paramagnetic, and the intermediate state is spin-paired [Tsibris, J. C. M. and Woody, R. W. (1970) Coord. Chem. Rev. 5, 417-458]. This hypothesis is supported by structural and spectroscopic evidence that the "paired-spin" state exists in both HP(red) and Fd(ox).
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185
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Watenpaugh KD, Sieker LC, Jensen LH, Legall J, Dubourdieu M. Structure of the oxidized form of a flavodoxin at 2.5-Angstrom resolution: resolution of the phase ambiguity by anomalous scattering. Proc Natl Acad Sci U S A 1972; 69:3185-8. [PMID: 4508313 PMCID: PMC389731 DOI: 10.1073/pnas.69.11.3185] [Citation(s) in RCA: 98] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Flavodoxin from Desulfovibrio vulgaris crystallizes in the oxidized form as well-formed, tetragonal bipyramids, space group P4(3)2(1)2, unit-cell parameters, a = b = 51.6 A, c = 139.6 A, 8 molecules per unit cell. The structure has been determined at 2.5-A resolution with phases based on a single isomorphous derivative. The phase ambiguity of a single derivative was resolved by use of anomalous scattering from the single-site Sm(+3). The molecule has a five-strand pleated sheet core with two long helices on either side of the sheet. The flavin mononucleotide lies mostly buried on one side of the molecule, but the methyl groups, one edge of the flavin, and part of the ribityl are exposed at the surface.
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186
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Watenpaugh KD, Sieker LC, Jensen LH, Le Gall J, Dubourdieu M. Flavodoxin from the sulfate reducing bacterium Desulfovibrio vulgaris. Its structure at 2.5 A resolution. ZEITSCHRIFT FUR NATURFORSCHUNG. TEIL B. ANORGANISCHE CHEMIE, ORGANISCHE CHEMIE, BIOCHEMIE, BIOPHYSIK, BIOLOGIE 1972; 27:1094-5. [PMID: 4405091 DOI: 10.1515/znb-1972-0931] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Crystals of oxidized Desulfovibrio vulgaris flavodoxin have been studied by X-ray diffraction techniques. The structure has been determined at 2.5 A resolution. The molecule consists of a pleated sheet core with two sections of helix on each side of the sheet. The FMN group is distinguishable: it is mostly burried but 7- and 8-Methyl groups appear to be at the surface of the protein.
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187
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188
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Watenpaugh KD, Sieker LC, Herriott JR, Jensen LH. The structure of a non-heme iron protein: rubredoxin at 1.5 Angstrom resolution. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1972; 36:359-67. [PMID: 4508149 DOI: 10.1101/sqb.1972.036.01.047] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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189
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Bremner JB, Warrener RN, Adman E, Jensen LH. The cis-syn photodimer of 1-thiauracil. A sulfur analog of the cis-syn photodimer of uracil. J Am Chem Soc 1971; 93:4574-9. [PMID: 5131157 DOI: 10.1021/ja00747a039] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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190
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Camerman A, Jensen LH, Cochran TG, Huitric AC. Absolute configuration of (+)-trans-2-o-tolylcyclohexanol by x-ray crystallography. J Pharm Sci 1970; 59:1675-6. [PMID: 5495503 DOI: 10.1002/jps.2600591133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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191
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Furberg S, Jensen LH. Crystal structure of thiocytosine. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 1970; 26:1260-8. [PMID: 5537182 DOI: 10.1107/s0567740870003989] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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192
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Adman E, Jensen LH. The crystal and molecular structure of the cis-syn photodimer of uracil. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 1970; 26:1326-34. [PMID: 5537185 DOI: 10.1107/s0567740870004077] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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193
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Herriott JR, Sieker LC, Jensen LH, Lovenberg W. Structure of rubredoxin: an x-ray study to 2.5 A resolution. J Mol Biol 1970; 50:391-406. [PMID: 5476919 DOI: 10.1016/0022-2836(70)90200-7] [Citation(s) in RCA: 151] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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194
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Camerman A, Jensen LH. 2-p-Toluidinyl-6-Naphthalene Sulfonate: Relation of Structure to Fluorescence Properties in Different Media. Science 1969; 165:493-5. [PMID: 17831036 DOI: 10.1126/science.165.3892.493] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Hydrated and anhydrous crystals of 2-p-toluidinyl-6-naphthalene sulfonate exhibit fluorescence spectra similar to those obtained for 2-p-toluidinyl-6-naphthalene sulfonate in water and in organic solvents, respectively. The molecular structure of anhydrous 2-p-toluidinyl-6-naphthalene sulfonate suggests extended electron resonance over the whole molecule and this is one of the causes of the spectral differences.
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195
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Sletten E, Sletten J, Jensen LH. The crystal and molecular structure of 6-mercaptopurine monohydrate. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 1969; 25:1330-8. [PMID: 5819641 DOI: 10.1107/s0567740869004018] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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196
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Sletten J, Sletten E, Jensen LH. A reinvestigation of 8-azaguanine monohydrate. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 1968; 24:1692-8. [PMID: 5756972 DOI: 10.1107/s0567740868004863] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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197
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198
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Watenpaugh K, Dow J, Jensen LH, Furberg S. Crystal and molecular structure of adenosine 3',5'-cyclic phosphate. Science 1968; 159:206-7. [PMID: 5634913 DOI: 10.1126/science.159.3811.206] [Citation(s) in RCA: 91] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The structure of adenosine 3',5'-cyclic phosphate has been determined by single-crystal x-ray diffraction. The two molecules in the asymmetric unit show different conformation about the glycosidic bond, while other structural details are essentially the same. The furanose rings are puckered with the C(4') atom out of the best four-atom plane. The bond lengths and angles appear to be normal.
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199
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Ammon HL, Jensen LH. The crystal structure of the dimeric acid product of 1-methyl-1,4-dihydronicotinamide. ACTA CRYSTALLOGRAPHICA 1967; 23:805-16. [PMID: 4229452 DOI: 10.1107/s0365110x67003731] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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200
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Jensen LH, Mabis AJ. Refinement of the structure of beta-tricaprin. ACTA CRYSTALLOGRAPHICA 1966; 21:770-81. [PMID: 6013555 DOI: 10.1107/s0365110x66003839] [Citation(s) in RCA: 89] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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