scholarly journals Tyrosine and tyrosinate fluorescence of pig intestinal Ca2+-binding protein

1987 ◽  
Vol 243 (2) ◽  
pp. 611-615 ◽  
Author(s):  
J D J O'Neil ◽  
T Hofmann
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Emission Spectrum ◽  
Hydroxy Group ◽  
Binding Proteins ◽  
Binding Protein ◽  
Emission Spectra ◽  
Difference Spectrum ◽  
Tyrosine Residue

The single tyrosine residue in both pig and cow intestinal Ca2+-binding proteins fluoresces at 303 nm although the crystal structure of the cow protein shows a hydrogen bond between the hydroxy group of the tyrosine and glutamate-38 [Szebenyi & Moffat (1986) J. Biol. Chem. 261, 8761-8777]. The latter interaction suggests that tyrosinate fluorescence should dominate the emission spectra of these proteins. A fluorescence difference spectrum, produced by subtracting the spectrum of free tyrosine from the spectrum of the protein, gives a peak at 334 nm due to ionized tyrosine. That this component of the emission spectrum is not due to a tryptophan-containing contaminant is shown by its elimination when the protein is denatured by guanidine and when glutamate-38 is protonated. We conclude that, in solution, the tyrosine residue in this protein interacts occasionally with glutamate-38 but that a permanent hydrogen bond is not formed.

scholarly journals Crystal structure of 7-{[bis(pyridin-2-ylmethyl)amino]methyl}-5-chloroquinolin-8-ol

2015 ◽  
Vol 71 (12) ◽  
pp. 1545-1547
Author(s):  
Koji Kubono ◽  
Kimiko Kado ◽  
Yukiyasu Kashiwagi ◽  
Keita Tani ◽  
Kunihiko Yokoi
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Hydroxy Group ◽  
Title Compound ◽  
Dihedral Angles ◽  
Π Interactions ◽  
Compound C ◽  
Centroid Distance ◽  
Ring Motif

In the title compound, C22H19ClN4O, the quinolinol moiety is almost planar [r.m.s. deviation = 0.012 Å]. There is an intramolecular O—H...N hydrogen bond involving the hydroxy group and a pyridine N atom forming anS(9) ring motif. The dihedral angles between the planes of the quinolinol moiety and the pyridine rings are 44.15 (9) and 36.85 (9)°. In the crystal, molecules are linkedviaC—H...O hydrogen bonds forming inversion dimers with anR44(10) ring motif. The dimers are linked by C—H...N hydrogen bonds, forming ribbons along [01-1]. The ribbons are linked by C—H...π and π–π interactions [inter-centroid distance = 3.7109 (11) Å], forming layers parallel to (01-1).

scholarly journals Crystal Structure ofPasteurella haemolyticaFerric Ion-binding Protein A Reveals a Novel Class of Bacterial Iron-binding Proteins

2003 ◽  
Vol 278 (42) ◽  
pp. 41093-41098 ◽  
Author(s):  
Stephen R. Shouldice ◽  
Douglas R. Dougan ◽  
Pamela A. Williams ◽  
Robert J. Skene ◽  
Gyorgy Snell ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Binding Proteins ◽  
Binding Protein ◽  
Protein A ◽  
Ion Binding ◽  
Iron Binding ◽  
Iron Binding Proteins

scholarly journals Paxillin family members function as Csk-binding proteins that regulate Lyn activity in human and murine platelets

2007 ◽  
Vol 403 (2) ◽  
pp. 275-281 ◽  
Author(s):  
Vipul B. Rathore ◽  
Masato Okada ◽  
Peter J. Newman ◽  
Debra K. Newman
Keyword(s):  
Binding Proteins ◽  
Binding Protein ◽  
Family Members ◽  
Adaptor Protein ◽  
Human Platelets ◽  
Src Family Kinases ◽  
Tyrosine Residue ◽  
Sh2 Domains ◽  
Ability To Act ◽  
Growth Factor Signalling

SFKs (Src family kinases) contribute importantly to platelet function in haemostasis. SFK activity is controlled by Csk (C-terminal Src kinase), which phosphorylates a C-terminal tyrosine residue on SFKs, resulting in inhibition of SFK activity. Csk is recruited to sites of SFK activity by tyrosine-phosphorylated Csk-binding proteins. Paxillin, a multidomain adaptor protein, has been shown to act as a Csk-binding protein and to inhibit Src activity during growth factor signalling. Human platelets express Hic-5, a member of the paxillin family; however, its ability to act as a Csk-binding protein has not been characterized. We sought to identify and characterize the ability of paxillin family members to act as Csk-binding proteins during platelet activation. We found that murine and human platelets differ in the complement of paxillin family members expressed. Human platelets express Hic-5, whereas murine platelets express paxillin and leupaxin in addition to Hic-5. In aggregating human platelets, Hic-5 was tyrosine phosphorylated and recruited Csk via its SH2 domains. In aggregating murine platelets, however, Csk bound preferentially to paxillin, even though both paxillin and Hic-5 were abundantly present and became tyrosine phosphorylated. The SFK Lyn, but not Src or Fyn, was associated with paxillin family members in resting and aggregated human and murine platelets. Lyn, however, was phosphorylated on its C-terminal inhibitory tyrosine residue only following platelet aggregation, which was coincident with recruitment of Csk to paxillin and/or Hic-5 in a manner dependent on prior αIIbβ3 engagement. These observations support the notion that Hic-5 and paxillin function as negative feedback regulators of SFKs in aggregated platelets and that, when both are present, paxillin is preferentially used.

scholarly journals Threefold helical assembly via hydroxy hydrogen bonds: the 2:1 co-crystal of bicyclo[3.3.0]octane-endo-3,endo-7-diol and bicyclo[3.3.0]octane-endo-3,exo-7-diol

2021 ◽  
Vol 77 (3) ◽  
pp. 270-276
Author(s):  
Isa Y. H. Chan ◽  
Mohan M. Bhadbhade ◽  
Roger Bishop
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Hydroxy Group ◽  
Network Structure ◽  
General Position ◽  
Three Dimensional ◽  
Screw Axis ◽  
Hydroxy Groups

Reduction of bicyclo[3.3.0]octane-3,7-dione yields a mixture of the endo-3,endo-7-diol and endo-3, exo-7-diol (C8H14O2) isomers (5 and 6). These form (5)2·(6) co-crystals in the monoclinic P21/n space group (with Z = 6, Z′ = 1.5) rather than undergoing separation by means of fractional recrystallization or column chromatography. The molecule of 5 occupies a general position, whereas the molecule of 6 is disordered over two orientations across a centre of symmetry with occupancies of 0.463 (2) and 0.037 (2). Individual diol hydroxy groups associate around a pseudo-threefold screw axis by means of hydrogen bonding. The second hydroxy group of each diol behaves in a similar manner, generating a three-dimensional hydrogen-bonded network structure. This hydrogen-bond connectivity is identical to that present in three known helical tubuland diol–hydroquinone co-crystals, and the new crystal structure is even more similar to two homologous aliphatic diol co-crystals.

scholarly journals Crystal structure ofrac-4-[2-(tert-butylazaniumyl)-1-hydroxyethyl]-2-(hydroxymethyl)phenol benzoate

2017 ◽  
Vol 73 (9) ◽  
pp. 1333-1335
Author(s):  
Wenju Liu ◽  
Qiliang Chen ◽  
Linda Yu
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Benzene Ring ◽  
Dihedral Angle ◽  
Hydroxy Group ◽  
Carboxyl Group ◽  
Medium Strength ◽  
Benzoate Anion

The title salt, C13H22NO3+·C7H5O2−, comprises one salbutamol cation {systematic name: 4-[2-(tert-butylazaniumyl)-1-hydroxyethyl]-2-(hydroxymethyl)phenol} and a benzoate anion. The cation shows disorder of the hydroxy group [occupancy ratio 0.738 (3):0.262 (3)] at the stereogenic C atom. The non-planar benzoate anion [the dihedral angle between the benzene ring and the carboxyl group is 11.30 (8)°] is linked to the salbutamol cation by a medium-strength O—H...O hydrogen bond. Other intermolecular O—H...O and N—H...O hydrogen bonds of weaker nature give rise to [001] chains.

scholarly journals Crystal structure of (E,E)-2′,4′-dihydroxyacetophenone azine dimethylformamide disolvate

2016 ◽  
Vol 72 (4) ◽  
pp. 467-469
Author(s):  
Wen-Juan Li ◽  
Hong-Fei Han
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Hydroxy Group ◽  
Title Compound ◽  
Maximum Deviation ◽  
Solvent Molecules

In the title compound {systematic name: 4,4′-[1,1′-(hydrazinediylidene)bis(ethan-1-yl-1-ylidene)]bis(benzene-1,3-diol)}, C16H16N2O4·2C3H7NO, the (E,E)-2′,4′-dihydroxyacetophenone azine molecule is centrosymmetric, the mid-point of the N—N bond being located on an inversion centre. All the non-H atoms of the azine molecule are approximately coplanar, the maximum deviation being 0.017 (2) Å. An intramolecular O—H...N hydrogen bond occurs between the azine N atom and the hydroxy group. In the crystal, azine and dimethylformamide solvent molecules are linked by O—H...O hydrogen bonds.

scholarly journals Crystal structure of methyl 2-[5-(2-hydroxyphenyl)-2H-tetrazol-2-yl]acetate

2017 ◽  
Vol 73 (12) ◽  
pp. 1971-1973 ◽  
Author(s):  
Seul Gi Lee ◽  
Ji Yeon Ryu ◽  
Junseong Lee
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Benzene Ring ◽  
Hydroxy Group ◽  
Title Compound ◽  
Methyl Acetate ◽  
Tetrazole Ring ◽  
Compound C ◽  
Phenol Ring

The title compound, C10H10N4O3, was synthesized by the esterification of hydroxyphenyl tetrazole. There is an intramolecular O—H...N hydrogen bond present involving the hydroxy group and the tetrazole ring. The tetrazole ring is inclined to the phenol ring by 2.85 (13)°, while the methyl acetate group is almost normal to the tetrazole ring, making a dihedral angle of 82.61 (14)°. In the crystal, molecules are linked by pairs of C—H...O hydrogen bonds, forming inversion dimers. Within the dimers, the phenol rings are linked by offset π–π interactions [intercentroid distance = 3.759 (2) Å]. There are no further significant intermolecular interactions present in the crystal. The hydroxy group is disordered about positions 2 and 6 on the benzene ring, with a refined occupancy ratio of 0.531 (5):0.469 (5).

scholarly journals Crystal structure of 2-(2,4-dichlorophenyl)-4-hydroxy-9-phenylsulfonyl-9H-carbazole-3-carbaldehyde

2014 ◽  
Vol 70 (12) ◽  
pp. 466-468 ◽  
Author(s):  
M. Umadevi ◽  
B. M. Ramalingam ◽  
R. Yamuna ◽  
A. K. Mohanakrishnan ◽  
G. Chakkaravarthi
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Hydroxy Group ◽  
Title Compound ◽  
Ring System ◽  
Compound C ◽  
The Mean ◽  
Graph Set

In the title compound, C25H15Cl2NO4S, the dichlorophenyl ring is twisted by 68.69 (11)° from the mean plane of the carbazole ring system [r.m.s. deviation = 0.084 (2)°]. The hydroxy group is involved in an intramolecular O—H...O hydrogen bond, which generates anS(6) graph-set motif. In the crystal, pairs of C—H...Cl hydrogen bonds link molecules into inversion dimers with anR22(26) motif. Weak C—H...O interactions further link these dimers into ribbons propagating in [100].

scholarly journals Crystal structure of (±)-(7RS,8SR)-7-methyl-1,4-dioxaspiro[4.5]decane-7,8-diol

2015 ◽  
Vol 71 (10) ◽  
pp. 1181-1184
Author(s):  
Takeshi Oishi ◽  
Hiroaki Yamamoto ◽  
Tomoya Sugai ◽  
Keisuke Fukaya ◽  
Yu Yamaguchi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydroxy Group ◽  
Cyclic Ether ◽  
Axial Position ◽  
Zigzag Chain ◽  
Compound C ◽  
Twist Conformation ◽  
The Mean ◽  
Ring Motif

In the title compound, C9H16O4, the five-membered dioxolane ring adopts a twist conformation; two adjacent C atoms deviate alternately from the mean plane of other atoms by −0.297 (4) and 0.288 (4) Å. The spiro-fused cyclohexane ring shows a chair form. The hydroxy group substituted in an axial position makes an intramolecular O—H...O hydrogen bond with one of the O atoms in the cyclic ether, forming anS(6) ring motif. In the crystal, the O—H...O hydrogen bond involving the equatorial hydroxy group connects the molecules into a zigzag chain with aC(5) motif running along thecaxis.

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