Abstract:
:The synthesis of activated sulfate (adenosine 5'-phosphosulfate, APS) and inorganic pyrophosphate from ATP and SO4 is remarkably unfavorable: K(eq) approximately 10(-8) under presumed, near-physiological conditions. Consequently, ATP sulfurylases, which catalyze APS synthesis, suffer approximately 10(8)-fold losses in catalytic efficiency in the forward (APS-synthesis) versus reverse reaction. Losses of this magnitude place this catalyst at risk of being unable to supply its nutrients to the cell in a timely fashion. ATP sulfurylase domains are often embedded in multifunctional complexes that are capable of also catalyzing the second of two steps in the sulfate activation pathway: the phosphorylation of APS to produce PAPS (3'-phosphoadenosine 5'-phosphosulfate). The colocalization of these activities in a single scaffold suggests that evolution might have worked around the inefficiency problem by fashioning a system capable of transferring APS directly between the active sites of the complex, thereby avoiding the solution-phase energetics. For these reasons, representatives from each of the three types of sulfate activating complex (SAC) [Homo sapiens (type I); Mycobacterium tuberculosis (type II); and Rhodobacter sphaeroides (type III)] were tested for the ability to channel APS. A channeling assay that optically detects solution-phase APS was devised with APS reductase from M. tuberculosis, a previously uncharacterized enzyme. Channeling was not detected in two of the three types of SAC; however, the type III SAC channels with high efficiency. Structural models of type III reveal a 75 A-long channel that interconnects active-site pairs in the complex and that opens and closes in response to occupancy of those sites.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Sun M,Leyh TSdoi
10.1021/bi060421esubject
Has Abstractpub_date
2006-09-26 00:00:00pages
11304-11issue
38eissn
0006-2960issn
1520-4995journal_volume
45pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::The chirality of sulfoxidation catalyzed by two cytochrome P-450 isozymes purified from phenobarbital-induced rat liver was studied by using 4-tolyl ethyl sulfide as a substrate. Both P-450 isoenzymes, termed PB-1 and PB-4, when reconstituted with purified rat liver NADPH-cytochrome P-450 reductase and cytochrome b5, ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00539a032
更新日期:1982-05-11 00:00:00
abstract::Recently, it was demonstrated that bifunctional catalase-peroxidases (KatGs) are found not only in archaea and bacteria but also in lower eukaryotes. Structural studies and preliminary biochemical data of the secreted KatG from the rice pathogen Magnaporthe grisea (MagKatG2) suggested both similar and novel features w...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b00831
更新日期:2015-09-08 00:00:00
abstract::Aromatic amino acids often flank the transmembrane alpha helices of integral membrane proteins. By favoring locations within the membrane-water interface of the lipid bilayer, aromatic residues Trp, Tyr, and sometimes Phe may serve as anchors to help stabilize a transmembrane orientation. In this work, we compare the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi500439x
更新日期:2014-06-10 00:00:00
abstract::We report here that the DNA strand scission by dynemicin A is not only sequence-specific but also conformation-specific. The salt-induced B----Z conformational transition dramatically enhanced the cleavage by dynemicin A in a B-Z junction region. By contrast, the bleomycin-Fe(II) complex, the elsamicin A-Fe(II) comple...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00144a019
更新日期:1992-07-28 00:00:00
abstract::Conformational selection and induced fit are two well-known mechanisms of allosteric protein-ligand interaction. Some proteins, like ubiquitin, have recently been found to exist in multiple conformations at equilibrium, suggesting that the conformational selection may be a general mechanism of interaction, in particul...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi900559k
更新日期:2009-08-04 00:00:00
abstract::Prodan [6-propionyl-2-(dimethylamine)naphthalene] is a hydrophobic fluorescent probe which is extremely sensitive to both the polarity and the hydrogen-bond donating capacity of the solvent. In binary mixtures of solvents, the hydrogen-bond donating effect on Prodan fluorescence saturates at relatively low concentrati...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00154a021
更新日期:1992-10-06 00:00:00
abstract::Electron paramagnetic resonance (EPR) imaging utilizing stable nitroxyl radicals is a promising technique for measuring free radical distribution, metabolism, and tissue oxygenation in organs and tissues [Kuppusamy, P., Chzhan, M., Vij, K., Shteynbuk, M., Lefer, D. J., Giannella, E., & Zweier, J. L. (1994) Proc. Natl....
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952857s
更新日期:1996-06-04 00:00:00
abstract::The prothrombinase complex is comprised of an enzyme, factor Xa, and a cofactor, factor Va, that each bind peripherally to membranes containing phosphatidylserine (PS) and activate the substrate, prothrombin. The mechanism by which the membrane contributes to enhanced catalytic efficacy of prothrombinase is not precis...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi047655n
更新日期:2005-03-15 00:00:00
abstract::Structural features of a 19-nucleotide RNA hairpin loop (5'-GGCGUACGUUUCGUACGCC-3'), a loop motif which occurs in eukaryotic 18S rRNA, have been derived using multidimensional heteronuclear NMR spectroscopy in combination with local conformational analysis and torsion angle distance geometry followed by restrained ene...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971207g
更新日期:1997-11-18 00:00:00
abstract::The catalytic and structural properties of divalent metal ion cofactor binding sites in the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae were investigated. Co(II)-substituted DapE enzyme was 25% more active than the Zn(II)-loaded form of the enzyme. Interestingly, Mn...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi034845+
更新日期:2003-09-16 00:00:00
abstract::A cross-linked tripeptide has been isolated from alkaline hydrolysates of NaB3H4-reduced calf bone collagen. The peptide contains dihydroxylysinonorleucine, the most abundant cross-link in bone collagen, and it has a single N-terminal proline and a single C-terminal valine. These amino acids are in peptide linkage wit...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00691a011
更新日期:1975-10-07 00:00:00
abstract::The vast majority of characterized oxygenases use bound cofactors to activate molecular oxygen to carry out oxidation chemistry. Here, we show that an enzyme of unknown activity, RhCC from Rhodococcus jostii RHA1, functions as an oxygenase, using 4-hydroxyphenylenolpyruvate as a substrate. This unique and complex reac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi501200j
更新日期:2015-02-10 00:00:00
abstract::The biosynthesis of osteocalcin (OC), a bone-specific, noncollagenous protein, is stringently regulated during differentiation of the osteoblast phenotype. Glucocorticoids, and also 1,25(OH)2D3, mediate the developmental regulation of OC gene transcription. In this study, we established that the -1097 to +23 promoter ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00093a022
更新日期:1993-10-26 00:00:00
abstract::The distance between the calcium site (site I) and the zinc site (site II) in alpha-lactalbumin was estimated from Forster energy-transfer measurements between donor Eu(III) [or Tb(III)] at site I and acceptor Co(II) at site II to be 11.5 +/- 1.5 A. Intersite distances were also measured between the bis-ANS [4,4'-bis[...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00365a024
更新日期:1986-08-26 00:00:00
abstract::The phosphorelay signal transduction pathway controls sporulation initiation in Bacillus subtilis. Transfer of a phosphoryl group from multiple kinases (KinA and KinB) through a single domain response regulator homologue (Spo0F), a phosphotransferase (Spo0B), and ultimately to a transcriptional regulator, (Spo0A) acti...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981340o
更新日期:1998-11-24 00:00:00
abstract::The temperature-composition phase diagram of mixed dimyristoylphosphatidylserine (DMPS) and dimyristoylphosphatidylcholine (DMPC) small unilamellar vesicles was determined in the presence and absence of bound bovine prothrombin by monitoring the phospholipid order-disorder phase separation using diphenylhexatriene (DP...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00480a023
更新日期:1990-07-17 00:00:00
abstract::Chicken liver phosphoenolpyruvate carboxykinase (PEPCK) was rapidly inactivated by micromolar concentrations of ferrous sulfate in the presence of ascorbate at pH 7.4. Omitting ascorbate or replacing the Fe2+ with Mn2+ or Mg2+ gives no inactivation. Mn2+, Mg2+, or Co2+ at 100-fold molar excess over Fe2+ offered comple...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi970574p
更新日期:1997-12-09 00:00:00
abstract::Virulent strains of Clostridium sordellii cause gangrenous myonecrosis in humans. The released lethal toxin (TcsL) and hemorrhagic toxin (TcsH) are regarded as the major virulence factors. TcsL inactivates low molecular weight GTP-binding proteins of the Rho/Ras subfamilies by monoglucosylation. In cultured cell lines...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi900964c
更新日期:2009-09-29 00:00:00
abstract::Seipin is a transmembrane protein that resides in the endoplasmic reticulum and concentrates at junctions between the ER and cytosolic lipid droplets. Mutations in the human seipin gene, including the missense mutation A212P, lead to congenital generalized lipodystrophy (CGL), characterized by the lack of normal adipo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi1013003
更新日期:2010-12-21 00:00:00
abstract::The ubiquitin signaling pathway consists of hundreds of enzymes that are tightly regulated for the maintenance of cell homeostasis. Parkin is an E3 ubiquitin ligase responsible for conjugating ubiquitin onto a substrate protein, which itself can be ubiquitinated. Ataxin-3 performs the opposing function as a deubiquiti...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi400780v
更新日期:2013-10-22 00:00:00
abstract::The malarial parasite Plasmodium falciparum can only synthesize pyrimidine nucleotides via the de novo pathway which is therefore a suitable target for development of antimalarial drugs. New assay procedures have been developed using high-pressure liquid chromatography (HPLC) which enable concurrent measurement of pyr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00183a033
更新日期:1994-05-03 00:00:00
abstract::Alanine scanning mutagenesis, double mutant cycles, and X-ray crystallography were used to characterize the interface between the anti-hen egg white lysozyme (HEL) antibody D1.3 and HEL. Twelve out of the 13 nonglycine contact residues on HEL, as determined by the high-resolution crystal structure of the D1.3-HEL comp...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi980148j
更新日期:1998-06-02 00:00:00
abstract::A gene encoding the high-potential iron-sulfur protein (HiPIP) was cloned from the purple photosynthetic bacterium Rubrivivax gelatinosus. An insertional disruption of this gene by a kanamycin resistance cartridge resulted in a significant decrease in the growth rate under photosynthetic growth conditions. Flash-induc...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026511a
更新日期:2002-11-26 00:00:00
abstract::ATP-binding cassette (ABC) transporters are ubiquitous in all three kingdoms of life and are implicated in many clinically relevant physiological processes. They couple the energy released by ATP hydrolysis to facilitate substrate translocation across cell membranes. The crystal structures of type II ABC importers hav...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.6b00386
更新日期:2016-12-13 00:00:00
abstract::We have investigated the effects of mixed Na+: Mg2+ ionic solutions on the stability of the nonspecific lac repressor-DNA complex. The effects of Mg2+ are simply interpreted in terms of its role as a competitor (with repressor) for DNA sites. From these studies, the binding constant of the Mg-DNA complex can be determ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00641a005
更新日期:1977-11-01 00:00:00
abstract::There are 10 transmembrane protein (TMEM) 16-family proteins in humans and mice. Among them, TMEM16F acts as a Ca(2+)-dependent phospholipid scramblase at the plasma membrane. However, how Ca(2+) activates TMEM16F's phospholipid-scramblase activity has not been elucidated. Here we found that in the presence of Ca(2+),...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.6b00176
更新日期:2016-06-14 00:00:00
abstract::Fluorescent nucleobase analogues are used extensively to probe the structure and dynamics of nucleic acids. The fluorescence of the adenine analogue 2-aminopurine and the cytosine analogue pyrrolocytosine is significantly quenched when the bases are located in regions of double-stranded nucleic acids. To allow more de...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060479t
更新日期:2006-08-01 00:00:00
abstract::The DNA interstrand cross-link (ICL) resulting from the C4'-oxidized abasic site (C4-AP) is a unique clustered lesion comprised of a cross-link adjacent to a nick. The ICL is a substrate for the UvrABC nucleotide excision repair system. The strand containing the nick is preferentially incised, but the nick influences ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi901006b
更新日期:2009-08-18 00:00:00
abstract::We have used [(1)H-(15)N]-HSQC NMR to investigate the structural changes that occur in both serpin and proteinase in forming the kinetically trapped covalent protein-protein complex that is the basis for serpin inhibition of serine proteinases. By alternately using (15)N-alanine specifically-labeled alpha(1)-proteinas...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi010100x
更新日期:2001-05-29 00:00:00
abstract::The crystal structure of netropsin bound to the decamer d(CGCAATTGCG) has been determined at 2.4 A resolution. This is the first example of a crystal structure of netropsin bound to decamer DNA. The central eight bases of each DNA single-strand base pair with a self-complementary strand to form an octamer B-DNA duplex...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9628228
更新日期:1997-04-22 00:00:00