Abstract：
:Class II MHC glycoproteins bind short (7-25 amino acid) peptides in an extended type II polyproline-like conformation and present them for immune recognition. Because empty MHC is unstable, measurement of the rate of the second-order reaction between peptide and MHC is challenging. In this report, we use dissociation of a pre-bound peptide to generate the active, peptide-receptive form of the empty class II MHC molecule I-Ek. This allows us to measure directly the rate of reaction between active, empty I-Ek and a set of peptides that vary in structure. We find that all peptides studied, despite having highly variable dissociation rates, bind with similar association rate constants. Thus, the rate-limiting step in peptide binding is minimally sensitive to peptide side-chain structure. An interesting complication to this simple model is that a single peptide can sometimes bind to I-Ek in two kinetically distinguishable conformations, with the stable peptide-MHC complex isomer forming much more slowly than the less-stable one. This demonstrates that an additional free-energy barrier limits the formation of certain specific MHC-peptide complex conformations.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Kasson PM,Rabinowitz JD,Schmitt L,Davis MM,McConnell HMdoi
10.1021/bi9921337subject
Has Abstractpub_date
2000-02-08 00:00:00pages
1048-58issue
5eissn
0006-2960issn
1520-4995pii
bi9921337journal_volume
39pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:The importance of two buried salt bridges in barnase in the stability of its folded state, the major transition rate for unfolding, and a folding intermediate has been analyzed by protein engineering, kinetic, and thermodynamic studies. The aspartate residues in the bridges Arg69-Asp93 and Arg83-Asp75 were replaced by...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi952930e
更新日期：1996-05-28 00:00:00
abstract：:Shiga toxin is a bacterial protein composed of one A and five B subunits. Its A chain possesses a protease sensitive loop (Cys-242-Cys-261) that is cleaved to produce an enzymatically active A1 domain and an A2 fragment associated with its B subunit pentamer. The proposed mode of action of the toxin is linked to its r...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi960177z
更新日期：1996-07-23 00:00:00
abstract：:Room temperature phosphorescence techniques were used to study the structural and dynamic features of the tryptophan residues in bovine alpha-crystallin. Upon excitation at 290 nm, the characteristic signature of tryptophan phosphorescence was observed with an emission maximum at 442 +/- 2 nm. The phosphorescence inte...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00439a027
更新日期：1989-06-27 00:00:00
abstract：:Apo-electron-transferring flavoprotein from pig kidney (apo-ETF) has been prepared by an acid ammonium sulfate procedure and reconstituted with FAD analogues to probe the flavin binding site. The 8-position of the bound flavin is accessible to solvent as judged by the reaction of 8-Cl-FAD-ETF with sodium sulfide and t...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00370a050
更新日期：1986-11-04 00:00:00
abstract：:This report presents evidence for interdomain steps of the ligand-coupled signal transduction mechanism of the oxygen receptor from Rhizobium meliloti, RmFixL. Photolysis of the CO adducts of heme domain (RmFixLN) and heme kinase (RmFixL*) proteins allowed tracking of second-order heme CO recombination reactions by tr...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi011237q
更新日期：2001-10-30 00:00:00
abstract：:Adenylosuccinate synthetase catalyzes the first committed step in the de novo biosynthesis of AMP, coupling L-aspartate and IMP to form adenylosuccinate. Km values of IMP and 2'-deoxy-IMP are nearly identical with each substrate supporting comparable maximal velocities. Nonetheless, the Km value for L-aspartate and th...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0607498
更新日期：2006-09-26 00:00:00
abstract：:The capsular polysaccharide (CPS) structure of Campylobacter jejuni contributes to its robust fitness. Many strains contain heptose moieties in their CPS units. The precursor heptose is GDP-d-glycero-α-d-manno-heptose; modifications to the stereochemistry at C3-C6 as well as additions of methyl and phosphoramidate gro...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.9b00548
更新日期：2019-09-17 00:00:00
abstract：:The substrate specificity of the beta-glucosidase (CelB) from the hyperthermophilic archaeon Pyrococcus furiosus, a family 1 glycosyl hydrolase, has been studied at a molecular level. Following crystallization and X-ray diffraction of this enzyme, a 3.3 A resolution structural model has been obtained by molecular repl...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi992463r
更新日期：2000-05-02 00:00:00
abstract：:The stoichiometry of cytochrome b559 (one or two copies) per reaction center of photosystem II (PSII) has been the subject of considerable debate. The molar ratio of cytochrome b559 has a number of significant implications on our understanding of the functional role of cytochrome b559, the mechanism of electron donati...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00161a024
更新日期：1992-11-24 00:00:00
abstract：:Histidine-40 is known to participate in phosphodiester transesterification catalyzed by the enzyme ribonuclease T1. A mutant enzyme with a lysine replacing the histidine-40 (His40Lys RNase T1) retains considerable catalytic activity [Steyaert, J., Hallenga, K., Wyns, L., & Stanssens, P. (1990) Biochemistry 29, 9064-90...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00161a009
更新日期：1992-11-24 00:00:00
abstract：:Human transferrin (Tf) is responsible for the binding and transport of iron in the bloodstream of vertebrates. Delivery of this bound iron to cells occurs by a process of receptor-mediated endocytosis during which Tf releases its iron at the reduced endosomal pH of approximately 5.6. Iron release from Tf involves a la...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi002050m
更新日期：2001-02-13 00:00:00
abstract：:An imidazole spin-label was used to study the role of tyrosyl residues in the reassociation process for the nucleosome core particle. The nucleosome core particle, containing 145 base pairs of DNA and a histone core (two each of the four histones H2S, H2B, H3, and H4), was isolated from chicken erythrocytes. Native pa...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00541a034
更新日期：1982-06-08 00:00:00
abstract：:Peripherin/rds is a 39 kDa integral membrane glycoprotein essential for normal photoreceptor cell development in vertebrates. It has been implicated in several human retinal degenerative diseases including retinitis pigmentosa and macular degeneration and is thought to play a structural role at photoreceptor outer seg...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00043a028
更新日期：1995-10-31 00:00:00
abstract：:The light-sensing outer segments of photoreceptor cells harbor hundreds of flattened membranous discs containing the visual pigment, rhodopsin, and all the proteins necessary for visual signal transduction. PRCD (progressive rod-cone degeneration) protein is one of a few proteins residing specifically in photoreceptor...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.6b00489
更新日期：2016-09-13 00:00:00
abstract：:The deacetylation of UDP-3-O-[(R)-3-hydroxymyristoyl]-N-acetylglucosamine (UDP-3-O-acyl-GlcNAc) by LpxC is the committed reaction of lipid A biosynthesis. CHIR-090, a novel N-aroyl-l-threonine hydroxamic acid, is a potent, slow, tight-binding inhibitor of the LpxC deacetylase from the hyperthermophile Aquifex aeolicus...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi6025165
更新日期：2007-03-27 00:00:00
abstract：:Artificial genetic systems have been developed by synthetic biologists over the past two decades to include additional nucleotides that form additional nucleobase pairs independent of the standard T:A and C:G pairs. Their use in various tools to detect and analyze DNA and RNA requires polymerases that synthesize duple...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi400558c
更新日期：2013-08-06 00:00:00
abstract：:In type 2 diabetics, the hormone amylin misfolds into amyloid plaques implicated in the destruction of the pancreatic β-cells that make insulin and amylin. The aggregative misfolding of amylin is pH-dependent, and exposure of the hormone to acidic and basic environments could be physiologically important. Amylin has t...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi401164k
更新日期：2014-01-21 00:00:00
abstract：:This paper presents the crystal structure of porcine pancreatic carboxypeptidase B (pp-CpB) in complex with a variety of thiol-based inhibitors that were developed as antagonists of activated thrombin-activatable fibrinolysis inhibitor (TAFIa). Recent studies have indicated that a selective inhibitor of TAFIa could en...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0501941
更新日期：2005-07-05 00:00:00
abstract：:The rates of inactivation of BF1 adenosinetriphosphatase (BF1-ATPase) from Escherichia coli by 7-chloro-4-nitro-2,1,3-benzoxadiazole, 1-fluoro-2,4-dinitrobenzene, 2,4,6-trinitrobenzenesulfonate, phenylglyoxal, and N,N'-dicyclohexylcarbodiimide have been measured in the presence and absence of various concentrations of...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00531a011
更新日期：1982-01-19 00:00:00
abstract：:Aromatic amine dehydrogenase (AADH) is the second enzyme known to possess the tryptophan tryptophylquinone (TTQ) prosthetic group. Its ability to catalyze the oxidative deamination of a wide range of aromatic and aliphatic amines has been investigated. Steady-state and transient kinetic studies of the reaction of AADH...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00003a015
更新日期：1995-01-24 00:00:00
abstract：:Phosphoprotein particles were isolated in their native state from the physiological fluid of the estuarine clam Rangia cuneata , and the characteristics of the mineral ion-protein complex which constitutes the native particle were investigated by using mineral ion binding and mineral ion exchange techniques. The parti...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00302a017
更新日期：1984-03-27 00:00:00
abstract：:Phosphatidylserine (PS) in the plasma membrane of nonactivated human platelets is almost entirely located on the cytoplasmic side. Stimulation of platelets with the Ca2+ ionophore A23187 or combined action of collagen plus thrombin results in a rapid loss of the asymmetric distribution of PS. Also, treatment with the ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00432a007
更新日期：1989-03-21 00:00:00
abstract：:2,3-Butanedione monoxime (BDM) reversibly inhibits force production in muscle. At least part of its action appears to be directly on the contractile apparatus. To understand better its mechanism of action, we studied the effect of BDM on the steps of myosin subfragment 1 Mg(2+)-ATPase in 0.1 M potassium acetate, pH 7....
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00163a036
更新日期：1992-12-08 00:00:00
abstract：:High-precision studies of oxygen binding in hemoglobin (HbA0) solutions at near-physiological concentrations (2-12 mM heme; pHs 7.0-9.1; various buffers) have led to an unanticipated result: an unmeasurably low contribution from the triply ligated species. We have obtained this result from new differential oxygen-bind...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00387a038
更新日期：1987-06-30 00:00:00
abstract：:L-alpha-Hydroxy acid oxidase (listed as EC 1.4.3.2, L-amino acid: O2 oxidoreductase) has been purified 100-fold from rat kidney to apparent homogeneity by gel electrophoresis. A subunit molecular weight of 47,500 was found by sodium dodecyl sulfate gel electrophoresis, but in contrast to previous reports, the enzyme h...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00683a005
更新日期：1975-06-17 00:00:00
abstract：:Horse heart cytochrome c has been modified by 8-azido-ATP and the electron-transfer activity of the modified cytochrome c's to bovine heart cytochrome c oxidase (CcO) under physiological ionic strengths has been studied by the laser flash photolysis technique with 5-deazariboflavin and EDTA as the electron donor. The ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00008a035
更新日期：1995-02-28 00:00:00
abstract：:The first transmembrane (TM1) helix in the red cell anion exchanger (AE1, Band 3, or SLC4A1) acts as an internal signal anchor that binds the signal recognition particle and directs the nascent polypeptide chain to the endoplasmic reticulum (ER) membrane where it moves from the translocon laterally into the lipid bila...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.6b00966
更新日期：2017-02-07 00:00:00
abstract：:The time course of changes in the intravesicular Ca2+ concentration ([Ca2+]i) in terminal cisternal sarcoplasmic reticulum vesicles upon the induction of Ca2+ release was investigated by using tetramethylmurexide (TMX) as an intravesicular Ca2+ probe. Upon the addition of polylysine at the concentration that led to th...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00235a017
更新日期：1991-05-28 00:00:00
abstract：:Atomic force microscopy (AFM) is a technique widely used to image protein-DNA complexes, and its application has now been extended to the measurements of protein-DNA binding constants and specificities. However, the spreading of the protein-DNA complexes on a flat substrate, generally mica, is required prior to AFM im...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi060293u
更新日期：2006-12-12 00:00:00
abstract：:The mechanism by which terminal guanidino nitrogen substituted analogues of amiloride inhibit Na-Ca exchange in purified cardiac sarcolemmal membrane vesicles has been investigated. These inhibitors block both Nai-dependent Ca2+ uptake and Nao-dependent Ca2+ efflux. Inhibition of Na-Ca exchange monitored in K+ is nonc...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00407a023
更新日期：1988-04-05 00:00:00
