Abstract:
:Escherichia coli PurK, a dimeric N5-carboxyaminoimidazole ribonucleotide (N5-CAIR) synthetase, catalyzes the conversion of 5-aminoimidazole ribonucleotide (AIR), ATP, and bicarbonate to N5-CAIR, ADP, and Pi. Crystallization of both a sulfate-liganded and the MgADP-liganded E. coli PurK has resulted in structures at 2.1 and 2.5 A resolution, respectively. PurK belongs to the ATP grasp superfamily of C-N ligase enzymes. Each subunit of PurK is composed of three domains (A, B, and C). The B domain contains a flexible, glycine-rich loop (B loop, T123-G130) that is disordered in the sulfate-PurK structure and becomes ordered in the MgADP-PurK structure. MgADP is wedged between the B and C domains, as with all members of the ATP grasp superfamily. Other enzymes in this superfamily contain a conserved Omega loop proposed to interact with the B loop, define the specificity of their nonnucleotide substrate, and protect the acyl phosphate intermediate formed from this substrate. PurK contains a minimal Omega loop without conserved residues. In the reaction catalyzed by PurK, carboxyphosphate is the putative acyl phosphate intermediate. The sulfate of the sulfate ion-liganded PurK interacts electrostatically with Arg 242 and the backbone amide group of Asn 245, components of the J loop of the C domain. This sulfate may reveal the location of the carboxyphosphate binding site. Conserved residues within the C-terminus of the C domain define a pocket that is proposed to bind AIR in collaboration with an N-terminal strand loop helix motif in the A domain (P loop, G8-L1). The P loop is proposed to bind the phosphate of AIR on the basis of similar binding sites observed in PurN and PurE and proposed in PurD and PurT, four other enzymes in the purine pathway.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Thoden JB,Kappock TJ,Stubbe J,Holden HMdoi
10.1021/bi991618ssubject
Has Abstractpub_date
1999-11-23 00:00:00pages
15480-92issue
47eissn
0006-2960issn
1520-4995pii
bi991618sjournal_volume
38pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Glutathione S-transferase, from the malarial parasite Plasmodium falciparum (PfGST), exerts a protective role in the organism and is thus considered an interesting target for antimalarial drug development. In contrast to other GSTs, it is present in solution as a tetramer and a dimer in equilibrium, which is induced b...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi400007g
更新日期:2013-03-19 00:00:00
abstract::We have studied the photoreaction of 8-methoxypsoralen (8-MOP), 4,5',8-trimethylpsoralen (TMP), and 4'-(hydroxymethyl)-4,5',8-trimethylpsoralen (HMT) with a pair of 18-base-long oligonucleotides in which a 14-base region is complementary. Only one 5'TpA site, favored for both monoadduct and cross-link formation with p...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00409a012
更新日期:1988-05-03 00:00:00
abstract::Paramagnetic agents produce line broadening and thus cancellation of anti phase cross-peak components in two-dimensional correlated nuclear magnetic resonance spectra. The specificity of this effect was examined to determine its utility for identifying surface residues of proteins. Ubiquitin and hen egg white lysozyme...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00495a005
更新日期:1990-10-30 00:00:00
abstract::The behavior of Ca2+-ATPase from sarcoplasmic reticulum in detergent solution was compared with that of Ca2+-ATPase which had been cleaved in half by limited trypsin digestion. Attempts to dissociate the fragments (I and II) with an excess of detergent micelles demonstrated that fragments I and II are structurally dep...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00612a028
更新日期:1978-09-19 00:00:00
abstract::Microdomains known as "rafts" have been isolated from many cell types as detergent-resistant membranes (DRMs) and are enriched in sphingolipids and cholesterol. However, there has been considerable controversy over whether such domains are found in native membranes or are artificially generated by the purification pro...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026107b
更新日期:2002-11-05 00:00:00
abstract::The reduction potentials of the compound II/ferric and compound I/compound II couples have been studied, using potassium hexachloroiridate as a mediator titrant, by thin-layer spectroelectrochemistry. Compound I, which is 2 equiv more oxidized than the ferric (i.e., resting) form of the enzyme, was reversibly formed v...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00009a017
更新日期:1995-03-07 00:00:00
abstract::PDZ domains are among the most abundant protein modules in the known genomes. Their main function is to provide scaffolds for membrane-associated protein complexes by binding to the cytosolic, C-terminal fragments of receptors, channels, and other integral membrane proteins. Here, using both heteronuclear NMR and sing...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi052225y
更新日期:2006-03-21 00:00:00
abstract::Dodecameric glutamine synthetase (GS) from bacteria is formed from two face-to-face hexameric rings of identical subunits. These highly symmetrical aggregates from some bacteria, including Escherichia coli, "stack" in the presence of Zn2+ and other divalent ions to generate protein tubes (phase I) and subsequently ass...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00254a001
更新日期:1994-12-20 00:00:00
abstract::Peptidylglycine monooxygenase (PHM) catalyzes the final step in the biosynthesis of amidated peptides that serve as important signaling molecules in numerous endocrine pathways. The catalytic mechanism has attracted much attention because of a number of unique attributes, including the presence of a pair of uncoupled ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi4015264
更新日期:2014-02-18 00:00:00
abstract::Naturally occurring interruptions in nonfibrillar collagen play key roles in molecular flexibility, collagen degradation, and ligand binding. The structural feature of the interruption sequences and the molecular basis for their functions have not been well studied. Here, we focused on a G5G type natural interruption ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b01010
更新日期:2018-02-20 00:00:00
abstract::Amyloid-beta (Abeta) peptide deposition as fibrillar senile plaques is a key element in the pathology of Alzheimer's disease. Here we present a high-resolution structure of an Abeta amyloid fibril using magnetically aligned preparations of a central Abeta domain which forms representative amyloid fibrils. Diffraction ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000637v
更新日期:2000-10-31 00:00:00
abstract::Resonance Raman spectra of squid rhodopsin have been obtained under a variety of temperature and illumination conditions. The data have been characterized in terms of spectral contributions from squid rhodopsin, isorhodopsin, bathorhodopsin, lumirhodopsin, mesorhodopsin, P-465, and acid metarhodopsin. The results are ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00615a018
更新日期:1978-10-31 00:00:00
abstract::To identify residues and segments in the central region of apolipoprotein A-I (apoA-I) that are important for the protein structure and stability, we studied the effects of four double charge ablations, D102A/D103A, E110A/E111A, R116V/K118A, and R160V/H162A, and two deletion mutations, Delta(61-78) and Delta(121-142),...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi051669r
更新日期:2006-01-31 00:00:00
abstract::Epitranscriptomic RNA modifications can serve as recognition elements for the recruitment of effector proteins (i.e., "readers") to modified transcripts. While these interactions play an important role in mRNA regulation, there is a major gap in our understanding of the sequence determinants critical for the binding o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.9b00485
更新日期:2019-08-06 00:00:00
abstract::Bacterial resistance to the aminoglycoside antibiotics is manifested primarily through the production of enzymes which covalently modify these drugs. The Enterococci and Staphylococci produce an ATP-dependent kinase, APH(3')-IIIa, which phosphorylates such antibiotics as kanamycin, amikacin, and neomycin, and this enz...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9603884
更新日期:1996-07-02 00:00:00
abstract::The interaction of bee venom melittin with dimyristolphosphatidylcholine (DMPC) selectively deuteriated in the choline head group has been studied by deuterium and phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy. The action of residual phospholipase A2 in melittin samples resulted in mixtures of DMPC and i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00392a033
更新日期:1987-09-08 00:00:00
abstract::Carbamoylation and reductive methylation of tubulin have been shown previously to inhibit microtubule assembly, probably by attack on essential internal lysine residues [Mellado, W., Slebe, J., & Maccioni, R.B. (1982) Biochem. J. 203, 675-681; Szasz, J., Burns, R., & Sternlicht, H. (1982) J. Biol. Chem. 257, 3697-3704...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00403a027
更新日期:1988-02-09 00:00:00
abstract::Organisms rely on regulation at the molecular level, such as the allosteric regulation of hemoglobin (Hb) function by anions, to meet challenges presented by changing environmental and physiological conditions. A comparison of the effects of anions on oxygenation, oxidation, and sulfhydryl reactivity of Hb leads us to...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971574s
更新日期:1998-01-13 00:00:00
abstract::The folding of many globular proteins from the unfolded (U) to the native (N) state appears to be describable by a two-state N ↔ U model, which has led to the general belief that protein folding occurs in a highly cooperative manner. One reason for the widespread belief in "two-state folding" is that protein folding r...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00698
更新日期:2018-10-09 00:00:00
abstract::N-RAP is a recently discovered muscle-specific protein that is concentrated at the myotendon junctions in skeletal muscle and at the intercalated disks in cardiac muscle. The C-terminal half of N-RAP contains a region with sequence homology to nebulin, while a LIM domain is found at its N-terminus. N-RAP is hypothesiz...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi982395t
更新日期:1999-05-11 00:00:00
abstract::Serine palmitoyltransferase (EC 2.3.1.50) catalyzes the condensation of L-serine and palmitoyl-CoA to yield 3-ketosphinganine in the first unique reaction of long-chain (sphingoid) base biosynthesis. The kinetic effects of changing the extracellular concentrations of the precursors for this pathway were studied with L...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00401a051
更新日期:1988-01-12 00:00:00
abstract::Several strains of Sphingobium chlorophenolicum have been isolated from soil that was heavily contaminated with pentachlorophenol (PCP), a toxic pesticide introduced in the 1930s. S. chlorophenolicum appears to have assembled a poorly functioning pathway for degradation of PCP by patching enzymes recruited via two ind...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi300261p
更新日期:2012-05-08 00:00:00
abstract::The alpha-helix [Pauling, L., Corey, R. B., & Branson, H. R. (1951) Proc. Natl. Acad. Sci. U.S.A. 37, 205-211] is a common motif in both proteins and peptides. Despite intense investigation, predictive understanding of helices is still lacking. A recent hypothesis [Presta, L. G., & Rose, G. D. (1988) Science 240, 1632...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00081a001
更新日期:1993-08-03 00:00:00
abstract::Monomeric sarcosine oxidase (MSOX) is a prototypical member of a recently recognized family of amine-oxidizing enzymes that all contain covalently bound flavin. Mutation of the covalent flavin attachment site in MSOX produces a catalytically inactive apoprotein (apoCys315Ala) that forms an unstable complex with FAD (K...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0607352
更新日期:2006-08-08 00:00:00
abstract::Two scorpion neurotoxins active only on insects, the insect toxins AaH IT1 and AaH IT2, were purified from the venom of scorpions Androctonus australis Hector collected in Tozeur (Tunisia) and characterized. AaH IT2 was sequenced and found to differ in four amino acid positions from AaH IT, the single previously seque...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00458a021
更新日期:1990-02-13 00:00:00
abstract::A type II topoisomerase is essential for decatenating DNA replication products, and it accomplishes this task by passing one DNA duplex through a transient break in a second duplex. The B' domain of topoisomerase II contains three highly conserved motifs, EGDSA, PL(R/K)GK(I/L/M)LNVR, and IMTD(Q/A)DXD. We have investig...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi991328b
更新日期:2000-02-15 00:00:00
abstract::Native calf thymus DNA was reacted with N-acetoxy-N-2-acetylaminofluorene (N-AcO-AAF) and its 7-fluoro and 7-iodo derivatives. Different ways of purification of the fluorene modified DNA samples were checked in order ot obtain a nucleic acid free from all noncovalently bound fluorene residues. The decrease in melting ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00660a027
更新日期:1976-07-27 00:00:00
abstract::RNA helicase DHX33 has been shown to participate in a variety of cellular activities, including ribosome biogenesis, protein translation, and gene transcription. We and others further discovered that DHX33 is strongly expressed in several types of human cancers and plays important roles in promoting cancer cell prolif...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00166
更新日期:2019-01-29 00:00:00
abstract::We present a study of the interactions between the lipase from Thermomyces lanuginosus (TlL) and the two microbially produced biosurfactants (BSs), rhamnolipid (RL) and sophorolipid (SL). Both RL and SL are glycolipids; however, RL is anionic, while SL is a mixture of anionic and non-ionic species. We investigate the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b00420
更新日期:2017-08-15 00:00:00
abstract::A cell-free system for synthesizing protein from wheat germ was used to translate the messenger RNA extracted from 16-day embryonic chick calvaria. A part of the product had properties similar to collagenous peptides and served as a substrate for prolyl hydroxylase, an enzyme specific for collagen. The level of potass...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00649a016
更新日期:1976-02-24 00:00:00