Related ArticlesA novel type of arabinoxylan arabinofuranohydrolase isolated from germinated barley analysis of substrate preference and specificity by nano-probe NMR.
Eur J Biochem. 2000 Nov;267(22):6633-41
Authors: Ferré H, Broberg A, Duus JO, Thomsen KK
An arabinoxylan arabinofuranohydrolase was isolated from barley malt. The enzyme preparation, Ara 1, contained two polypeptides with apparent molecular masses of approximately 60 and approximately 66 kDa, a pI of 4.55 and almost identical N-terminal amino-acid sequences. With p-nitrophenyl alpha-L-arabinofuranoside (pNPA) as substrate, Ara 1 exhibited a Km of 0.5 mM and a Vmax of 6.7 micromol. min-1.(mg of protein)-1. Maximum activity was displayed at pH 4.2 and 60 degrees C, and, under these conditions, the half-life of the enzyme was 8 min. The Ara 1 preparation showed no activity against p-nitrophenyl alpha-L-arabinopyranoside or p-nitrophenyl beta-D-xylopyranoside. Substrate preference and specificity were investigated using pure oligosaccharides and analysis by TLC and nano-probe NMR. Ara 1 released arabinose from high-molecular-mass arabinoxylan and arabinoxylan-derived oligosaccharides but was inactive against linear or branched-chain arabinan. Arabinose was readily released from both singly and doubly substituted xylo-oligosaccharides. Whereas single 2-O-linked and 3-O-linked arabinose substituents on non-reducing terminal xylose were released at similar rates, there was a clear preference for 2-O-linked arabinose on internal xylose residues. When Ara 1 acted on oligosaccharides with doubly substituted, non-reducing terminal xylose, the 3-O-linked arabinose group was preferred as the initial point of attack. Oligosaccharides with doubly substituted internal xylose were poor substrates and no preference could be determined. The enzyme described here is the first reported arabinoxylan arabinofuranohydrolase which is able to release arabinose from both singly and doubly substituted xylose, and it hydrolyses p-nitrophenyl alpha-L-arabinofuranoside at a rate similar to that observed for oligosaccharide substrates.
[NMR paper] NMR solution structure of the isolated Apo Pin1 WW domain: comparison to the x-ray cr
NMR solution structure of the isolated Apo Pin1 WW domain: comparison to the x-ray crystal structures of Pin1.
Related Articles NMR solution structure of the isolated Apo Pin1 WW domain: comparison to the x-ray crystal structures of Pin1.
Biopolymers. 2002 Feb;63(2):111-21
Authors: Kowalski JA, Liu K, Kelly JW
The NMR solution structure of the isolated Apo Pin1 WW domain (6-39) reveals that it adopts a twisted three-stranded antiparallel beta-sheet conformation, very similar to the structure exhibited by the crystal of this domain in the...
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[NMR paper] NMR structure of the haem core of a novel tetrahaem cytochrome isolated from Shewanel
NMR structure of the haem core of a novel tetrahaem cytochrome isolated from Shewanella frigidimarina: identification of the haem-specific axial ligands and order of oxidation.
Related Articles NMR structure of the haem core of a novel tetrahaem cytochrome isolated from Shewanella frigidimarina: identification of the haem-specific axial ligands and order of oxidation.
FEBS Lett. 2001 Jan 26;489(1):8-13
Authors: Pessanha M, Brennan L, Xavier AV, Cuthbertson PM, Reid GA, Chapman SK, Turner DL, Salgueiro CA
The tetrahaem cytochrome isolated...
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[NMR paper] NMR structure of the Streptomyces metalloproteinase inhibitor, SMPI, isolated from St
NMR structure of the Streptomyces metalloproteinase inhibitor, SMPI, isolated from Streptomyces nigrescens TK-23: another example of an ancestral beta gamma-crystallin precursor structure.
Related Articles NMR structure of the Streptomyces metalloproteinase inhibitor, SMPI, isolated from Streptomyces nigrescens TK-23: another example of an ancestral beta gamma-crystallin precursor structure.
J Mol Biol. 1998 Sep 18;282(2):421-33
Authors: Ohno A, Tate S, Seeram SS, Hiraga K, Swindells MB, Oda K, Kainosho M
The Streptomyces metalloproteinase...
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[NMR paper] Native-like beta-hairpin structure in an isolated fragment from ferredoxin: NMR and C
Native-like beta-hairpin structure in an isolated fragment from ferredoxin: NMR and CD studies of solvent effects on the N-terminal 20 residues.
Related Articles Native-like beta-hairpin structure in an isolated fragment from ferredoxin: NMR and CD studies of solvent effects on the N-terminal 20 residues.
Protein Eng. 1996 Jul;9(7):559-65
Authors: Searle MS, Zerella R, Williams DH, Packman LC
The conformational properties of protein fragments have been widely studied as models of the earliest initiation events in protein folding. While...
[NMR paper] A biochemical and NMR spectroscopic study of hydrazine in the isolated rat hepatocyte
A biochemical and NMR spectroscopic study of hydrazine in the isolated rat hepatocyte.
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Arch Toxicol. 1992;66(9):660-8
Authors: Ghatineh S, Morgan W, Preece NE, Timbrell JA
Using isolated rat hepatocytes the biochemical effects of hydrazine have been investigated using both conventional assay techniques and high resolution proton NMR. High resolution proton NMR revealed that hydrazine caused a significant increase in alanine and lactate...
A novel type of arabinoxylan arabinofuranohydrolase isolated from germinated barley a
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