Abstract：
:Ketosteroid isomerase (KSI) is one of the most proficient enzymes catalyzing an allylic isomerization reaction at a diffusion-controlled rate. In this study of KSI, we have detailed the structures of its active site, the role of various catalytic residues, and have explained the origin of the its fast reactivity by carrying out a detailed investigation of the enzymatic reaction mechanism. This investigation included the X-ray determination of 15 crystal structures of two homologous enzymes in free and complexed states (with inhibitors) and extensive ab initio calculations of the interactions between the active sites and the reaction intermediates. The catalytic residues, through short strong hydrogen bonds, play the role of charge buffer to stabilize the negative charge built up on the intermediates in the course of the reaction. The hydrogen bond distances in the intermediate analogues are found to be about 0.2 A shorter in the product analogues both experimentally and theoretically.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Oh KS,Cha SS,Kim DH,Cho HS,Ha NC,Choi G,Lee JY,Tarakeshwar P,Son HS,Choi KY,Oh BH,Kim KSdoi
10.1021/bi001629hsubject
Has Abstractpub_date
2000-11-14 00:00:00pages
13891-6issue
45eissn
0006-2960issn
1520-4995pii
bi001629hjournal_volume
39pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:Several recent studies have provided evidence that LIN28, a cytoplasmic RNA-binding protein, inhibits the biogenesis of members of the let-7 microRNA family at the Dicer step in both mammals and Caenorhabditis elegans. However, the precise mechanism of inhibition is still poorly understood. Here we report on an in vit...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi200851d
更新日期：2011-09-06 00:00:00
abstract：:Cerebrovascular deposition of fibrillar 39-42 amino acid amyloid beta-protein (Abeta), a condition known as cerebral amyloid angiopathy (CAA), is a key pathological feature of Alzheimer's disease and related disorders including hereditary cerebral hemorrhage with amyloidosis-Dutch type (HCHWA-D). Severe cases of CAA, ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0002840
更新日期：2000-06-27 00:00:00
abstract：:This paper characterizes the low-affinity ligand binding interactions of a fluorinated volatile anesthetic, isoflurane (CHF2OCHClCF3), with bovine serum albumin (BSA) using 19F-NMR transverse relaxation (T2). 19F-NMR spectra of isoflurane in aqueous BSA reveal a single isoflurane trifluoromethyl resonance, indicative ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00146a007
更新日期：1992-08-11 00:00:00
abstract：:A mechanism by which the Klenow fragment of DNA polymerase I monitors the geometry of the base pairs may involve hydrogen bonds between the polymerase and the minor groove of the nascent base pair. The involvement of the 3-position of guanine in the template strand was examined by synthesizing oligodeoxynucleotides co...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971253g
更新日期：1997-10-28 00:00:00
abstract：:As discussed in the accompanying paper [Markland, W., Ley, A. C., & Ladner, R. C. (1996) Biochemistry 35, 8045-8057], we generated libraries from the first Kunitz domain of human lipoprotein-associated coagulation inhibitor (LACI-D1) using multivalent M13 III display and derived potent inhibitors of human plasmin (PLA...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi952629y
更新日期：1996-06-18 00:00:00
abstract：:The development of inhibitors of insulin-regulated aminopeptidase (IRAP), a membrane-bound zinc metallopeptidase, is a promising approach for the discovery of drugs for the treatment of memory loss such as that associated with Alzheimer's disease. There is, however, no consensus in the literature about the mechanism b...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi101893w
更新日期：2011-04-05 00:00:00
abstract：:In search of the regulation mechanisms for isoform specific myosin assembly, we have used the COOH-terminal fragments of nonmuscle myosin isoforms MIIA and MIIB (MIIA(F46) and MIIB(alpha)(F47)) as a model system. Phosphorylation by protein kinase C (PK C) or casein kinase II (CK II) within or near the nonhelical tail-...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi000347e
更新日期：2000-09-19 00:00:00
abstract：:The preparation of native alpha- and beta-chains of carp hemoglobin and the preparation of the hybrid hemoglobin alpha(carp):beta(human), hybrid I, are described. CO association and dissociation kinetics were determined for the hybrid hemoglobin alpha(carp):beta(human) as a function of fractional saturation by stopped...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00305a011
更新日期：1984-05-08 00:00:00
abstract：:We have analyzed by band-shift assays HeLa cell protein-DNA interactions on a stable cruciform DNA molecule. The stable cruciform was formed by heteroduplexing the HindIII-SphI fragment of SV40 virus DNA that contains the origin of replication with a derivative mutant containing a heterologous substitution at the cent...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00251a030
更新日期：1994-11-29 00:00:00
abstract：:The minimum oligosaccharide structure required for binding to the potent HIV-inactivating protein cyanovirin-N (CV-N) was determined by saturation-transfer difference (STD) NMR spectroscopy. Despite the low molecular mass of the protein (11 kDa), STD-NMR spectroscopy allowed the precise atomic mapping of the interacti...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi048676k
更新日期：2004-11-09 00:00:00
abstract：:The ability of DNA topoisomerase I to mediate the formation of structurally modified DNA duplexes was studied utilizing suicide substrates containing high-efficiency cleavage sites and acceptor oligonucleotides in which the 5'-terminal nucleotides were varied. When the substrates were nicked duplexes, the divalent cat...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi972707c
更新日期：1998-02-24 00:00:00
abstract：:15N-labeled hen lysozyme has been studied by 2D and 3D NMR in order to characterize its dynamic behavior. The resonances of all main-chain amide nitrogen atoms were assigned, as were resonances of nitrogen atoms in 28 side chains. Relaxation measurements for the main-chain and arginine and tryptophan side-chain 15N nu...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00012a023
更新日期：1995-03-28 00:00:00
abstract：:UDP-glucose:glycoprotein glucosyltransferase (UGT) is a soluble protein of the endoplasmic reticulum (ER) that operates as a gatekeeper for quality control by preventing transport of improperly folded glycoproteins out of the ER. We report the isolation of two cDNAs encoding human UDP-glucose:glycoprotein glucosyltran...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9916473
更新日期：2000-03-07 00:00:00
abstract：:Cdc31, the Saccharomyces cerevisiae centrin, is an EF-hand calcium-binding protein essential for the cell division and mRNA nuclear export. We used biophysical techniques to investigate its calcium, magnesium, and protein target binding properties as well as their conformations in solution. We show here that Cdc31 dis...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi200518d
更新日期：2011-07-26 00:00:00
abstract：:Two tetrapeptide sequence homologies between mouse epidermal growth factor precursor (mEGFP) and human follitropin (FSH) were revealed by a computer program that identifies identical residues among polypeptide sequences. The two tetrapeptides, Lys-Thr-Cys-Thr (KTCT) and Thr-Arg-Asp-Leu (TRDL), are present in the hormo...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00357a053
更新日期：1986-05-06 00:00:00
abstract：:Sensory rhodopsin I (SRI) is a seven-transmembrane helix retinylidene protein that mediates color-sensitive phototaxis responses through its bound transducer HtrI in the archaeon Halobacterium salinarum. Deprotonation of the Schiff base attachment site of the chromophore accompanies formation of the SRI signaling stat...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi991180w
更新日期：1999-10-05 00:00:00
abstract：:G-Actin is a globular protein (Mr 42 300) known to have three cysteine residues that are at least partially exposed and chemically reactive (Cys-10, -284, and -374). When G-actin was reacted with 3-bromo-1,1,1-trifluoropropanone, three resolvable 19F resonances were observed in the 19F NMR spectrum. This fluorinated G...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00356a050
更新日期：1986-04-22 00:00:00
abstract：:The three-dimensional structure of oryzacystatin-I, a cysteine proteinase inhibitor of the rice, Oryza sativa L. japonica, has been determined in solution at pH 6.8 and 25 degrees C by (1)H and (15)N NMR spectroscopy. The main body (Glu13-Asp97) of oryzacystatin-I is well-defined and consists of an alpha-helix and a f...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0006971
更新日期：2000-12-05 00:00:00
abstract：:The physicochemical and catalytic properties of thioredoxin-T' are described. This complemented protein structure consists of a 1:1 complex between the inactive fragments thioredoxin-T-(1--73) and thioredoxin T-(74--108). These are generated by selective trypsin cleavage at Arg-73 in lysine-modified and denatured Esch...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00592a010
更新日期：1979-12-11 00:00:00
abstract：:The far-ultraviolet circular dichroism spectra of bovine and human prothrombin, prothrombin fragment 1, prethrombin 1, prothrombin fragment 2, and prethrombin 2 (prethrombin 2des(1--13)) were determined and the method of Chen et al. [Chen, Y. H., Yang, J. T., & Martinez, H. M. (1972) Biochemistry 11, 4120--4131; Chen,...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00577a017
更新日期：1979-05-15 00:00:00
abstract：:Nitric oxide synthases (NOSs) are proposed to generate NO and citrulline from L-arginine in two steps: initial N-hydroxylation to generate Nomega-hydroxyarginine (NOHA) followed by a three-electron oxidation of the hydroxylated nitrogen to form products. Both steps consume NADPH and may involve heme iron-based activat...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971414g
更新日期：1997-09-09 00:00:00
abstract：:Exogenous mannosylphosphoryldolichol (Man-P-Dol) has previously been shown to stimulate UDP-GlcNAc:dolichyl phosphate N-acetylglucosamine 1-phosphate transferase (GPT1), the enzyme catalyzing the biosynthesis of N-acetylglucosaminylpyrophosphoryldolichol (GlcNAc-P-P-Dol). To define the structural specificity of the ma...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00200a036
更新日期：1994-08-30 00:00:00
abstract：:Apolipoprotein (apo) B, the major protein component of the atherogenic low-density lipoprotein (LDL), has a pentapartite structure, NH2-betaalpha1-beta1-alpha2-beta2-alpha3-COOH, the beta domains containing multiple amphipathic beta strands and the alpha domains containing multiple amphipathic alpha helixes. We recent...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi011757l
更新日期：2002-06-04 00:00:00
abstract：:Helicases unwind double-stranded nucleic acids, remove secondary structures from single-stranded nucleic acids, and remove proteins bound to nucleic acids. For many helicases, the mechanisms for these different functions share the ability to translocate with a directional bias as a result of ATP binding and hydrolysis...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.5b00214
更新日期：2015-07-14 00:00:00
abstract：:Ca2+-induced fusion of phospholipid vesicles (phosphatidylcholine/phosphatidic acid, 9:1 mol/mol) prepared by ethanolic injection was followed by five different procedures: resonance energy transfer, light scattering, electron microscopy, intermixing of aqueous content, and gel filtration through Sepharose 4-B. The fi...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00329a015
更新日期：1985-04-09 00:00:00
abstract：:Two oxygenated iron-cobalt hybrid hemoglobins (Hbs), (alpha Co-O2 beta Fe-O2)2 and (alpha Fe-O2 beta Co-O2)2, were studied by electron spin echo envelope modulation (ESEEM) spectroscopy in order to measure (i) electron-nuclear hyperfine and nuclear quadrupole coupling to the N epsilon of the proximal histidyl imidazol...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00020a036
更新日期：1995-05-23 00:00:00
abstract：:The transglutaminase Factor XIII (FXIII) catalyzes the formation of covalent cross-links between adjacent noncovalently associated fibrin chains in blood coagulation. The resulting covalently cross-linked hard clot is much more mechanically stable and resistant to proteolytic degradation. FXIII is activated by the ser...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi049260+
更新日期：2004-08-03 00:00:00
abstract：:Di-leucine motifs have been implicated in the internalization or degradation of many membrane proteins. The epidermal growth factor receptor (EGFR) contains two di-leucine residues at 658 (TLRRLLQER) and 679 (NQALLRIL). To determine the role of these di-leucine motifs in regulating EGF receptor expression, activity, o...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi961630+
更新日期：1996-11-19 00:00:00
abstract：:The mechanism by which the heme-containing peroxidase, chloroperoxidase, is able to chlorinate substrates is poorly understood. One approach to advance our understanding of the mechanism of the enzyme is to determine those factors which contribute to its stability. In particular, under alkaline conditions, chloroperox...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi961512m
更新日期：1996-11-19 00:00:00
abstract：:Two series of experiments were carried out to characterize (a) peptide fragments of sarcoplasmic reticulum (SR) ATPase, based on proteolysis with different enzymes and distribution of known labels, and (b) specific labeling and functional inactivation patterns, following ATPase derivatization with dicyclohexylcarbodii...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00405a061
更新日期：1988-03-08 00:00:00
