Abstract：
:Conformational factors that predicate selectivity for valine or isoleucine binding to IlvN leading to the regulation of aceto hydroxy acid synthase I (AHAS I) of Escherichia coli have been determined for the first time from high-resolution (1.9-2.43 Å) crystal structures of IlvN·Val and IlvN·Ile complexes. The valine and isoleucine ligand binding pockets are located at the dimer interface. In the IlvN·Ile complex, among residues in the binding pocket, the side chain of Cys43 is 2-fold disordered (χ1 angles of gauche- and trans). Only one conformation can be observed for the identical residue in the IlvN·Val complexes. In a reversal, the side chain of His53, located at the surface of the protein, exhibits two conformations in the IlvN·Val complex. The concerted conformational switch in the side chains of Cys43 and His53 may play an important role in the regulation of the AHAS I holoenzyme activity. A significant result is the establishment of the subunit composition in the AHAS I holoenzyme by analytical ultracentrifugation. Solution nuclear magnetic resonance and analytical ultracentrifugation experiments have also provided important insights into the hydrodynamic properties of IlvN in the ligand-free and -bound states. The structural and biophysical data unequivocally establish the molecular basis for differential binding of the ligands to IlvN and a rationale for the resistance of IlvM to feedback inhibition by the branched-chain amino acids.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Bansal A,Karanth NM,Demeler B,Schindelin H,Sarma SPdoi
10.1021/acs.biochem.9b00050subject
Has Abstractpub_date
2019-04-16 00:00:00pages
1992-2008issue
15eissn
0006-2960issn
1520-4995journal_volume
58pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:Cellular toxicity resulting from nucleation-dependent polymerization of amyloid beta-peptide (Abeta) is considered to be a major and possibly the primary component of Alzheimer's disease (AD). Inhibition of Abeta polymerization has thus been identified as a target for the development of therapeutic agents for the trea...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi982824n
更新日期：1999-05-25 00:00:00
abstract：:DNA polymerase β (Pol β) is a key enzyme in mammalian base excision repair (BER), contributing stepwise 5'-deoxyribose phosphate (dRP) lyase and "gap-filling" DNA polymerase activities. The lyase reaction is believed to occur via a β-elimination reaction following the formation of a Schiff base between the dRP group a...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.6b00807
更新日期：2017-01-24 00:00:00
abstract：:Conformations of (R)-alpha-(N6-adenyl)styrene oxide adducts at positions X6 in d(CGGACXAGAAG).d(CTTCTTGTCCG) and X7 in d(CGGACAXGAAG).d(CTTCTTGTCCG), incorporating codons 60, 61 (underlined), and 62 of the human n-ras protooncogene, were refined from 1H NMR data. These were the R(61,2) and R(61,3) adducts. Chemical sh...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00043a008
更新日期：1995-10-31 00:00:00
abstract：:Fesselin is a proline-rich actin-binding protein that was isolated from avian smooth muscle. Fesselin bundles actin and accelerates actin polymerization by facilitating nucleation. We now show that this polymerization of actin can be regulated by Ca(2+)-calmodulin. Fesselin was shown to bind to immobilized calmodulin ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0487490
更新日期：2004-11-02 00:00:00
abstract：:Integral membrane proteins, which include many cellular effector proteins and drug targets, can be difficult to produce, purify, and manipulate. Although the isolated ectodomains of many membrane proteins can be expressed as water soluble proteins, biological activity is frequently lost when these proteins are release...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi052600m
更新日期：2006-03-21 00:00:00
abstract：:The extent of nativeness of the stable conformation of the thermolysin fragment containing the carboxyl-terminal third of the protein (from residues 206 to 316, denoted fragment FII) was examined by its immunogenic and antigenic characteristics. Antisera elicited in rabbits by either intact thermolysin or fragment FII...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00538a007
更新日期：1982-04-27 00:00:00
abstract：:S100 beta is a calcium-binding protein, which regulates the activities of several enzymes and inhibits the phosphorylation of a variety of protein kinase C substrates in a calcium-dependent manner. The protein was recently found to activate a retinal membrane guanylate cyclase, and in this paper, we report that it inh...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9802115
更新日期：1998-07-28 00:00:00
abstract：:The tertiary structure of apolipoprotein (apo) A-I and the contributions of structural domains to the properties of the protein molecule are not well defined. We used a series of engineered human and mouse apoA-I molecules in a range of physical-biochemical measurements to address this issue. Circular dichroism measur...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi702332b
更新日期：2008-02-19 00:00:00
abstract：:The hydrogen exchange behavior of a four-helix bundle protein in low concentrations of denaturant reveals some partially unfolded forms that are significantly more stable than the fully unfolded state. Kinetic folding of the protein, however, is apparently two-state in the absence of the accumulation of early folding ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi025872n
更新日期：2002-06-25 00:00:00
abstract：:Hydroxyl radical induced formation of a DNA-protein cross-link involving thymine and tyrosine in nucleohistone is described. Hydroxyl radicals were generated in N2O-saturated aqueous solution by ionizing radiation. Samples of nucleohistone were hydrolyzed with HCl and trimethylsilylated. Analysis of irradiated samples...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00434a071
更新日期：1989-04-18 00:00:00
abstract：:The effect of mutating Gly 478 to Ala in rat cytochrome P450 2B1 on the metabolism of N-benzyl-1-aminobenzotriazole was investigated. The 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity of the wild-type enzyme was completely inactivated by incubating with 1 microM BBT. The G478A mutant, however, was not i...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971064y
更新日期：1997-09-30 00:00:00
abstract：:The mechanism by which acyl-CoA dehydrogenases initiate catalysis was studied by using p-substituted phenylacetyl-CoAs (substituents-NO2, -CN, and CH3CO-), 3S-C8-, and 3'-dephospho-3S-C8CoA. These analogues lack a beta C-H and cannot undergo alpha,beta-dehydrogenation. Instead they deprotonate at alpha C-H at pH > or ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971827h
更新日期：1998-02-17 00:00:00
abstract：:HK31 (S565-K595) has previously been shown to encompass the binding domain for plasma prekallikrein (PK) within domain 6 of high molecular weight kininogen (HK). The complementary binding domain for HK within PK is mapped to PK56 (F56-G86), in the apple 1 domain, and to PK266 (K266-C295), in the apple 4 domain. Isothe...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi960547j
更新日期：1996-10-01 00:00:00
abstract：:The photoaffinity reagent 6-azido-L-tryptophan was synthesized by chemical methods. It binds reversibly in the dark to the alpha 2 beta 2 complex of tryptophan synthase of Escherichia coli and forms a quinonoid intermediate with enzyme-bound pyridoxal phosphate (lambda max = 476 nm). The absorbance of this chromophore...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00338a031
更新日期：1985-08-13 00:00:00
abstract：:Volumetric characteristics of protein recognition events determine the direction of pressure-induced shifts in the recognition reaction, while also providing insights into the structural, dynamic, and hydration changes. We report changes in volume, ΔV, and adiabatic compressibility, ΔK(S), accompanying the binding of ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi3006994
更新日期：2012-07-24 00:00:00
abstract：:The chromatin-associated high-mobility group (HMG) proteins of the plant HMGB family are characterized by a central HMG-box domain that is flanked by a basic N-terminal and an acidic C-terminal domain. By functional interaction with certain transcription factors, HMGB proteins contribute to transcriptional regulation....
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi6024947
更新日期：2007-05-29 00:00:00
abstract：:The proximal bond between the iron atom of the heme group and the N epsilon of histidine F8 in myoglobin (Mb) and hemoglobin (Hb) is presumed to be an important determinant of heme binding, protein structure, and oxygen binding. Here a system is described in which the proximal ligand is provided intermolecularly by th...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00187a023
更新日期：1994-05-31 00:00:00
abstract：:In order to quantitate the contributions of the polar, uncharged amino acids to the stability of the native state of staphylococcal nuclease, each of the 13 alanines, 9 glycines, 9 threonines, 6 prolines, 6 glutamines, 6 asparagines, and 3 serines was substituted, either with both alanine and glycine or with 1 of thes...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00140a005
更新日期：1992-06-30 00:00:00
abstract：:N-Linked sugar chains were liberated by hydrazinolysis from porcine zona pellucida glycoproteins obtained from ovarian follicular oocytes. Neutral sugar chains were separated from acidic ones by paper electrophoresis and fractionated with a serial lectin column chromatography and Bio-Gel P-4 column chromatography. The...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00222a012
更新日期：1991-02-26 00:00:00
abstract：:The interaction of alamethicin with artificial lecithin multilamellar dispersions was investigated by nuclear magnetic resonance (NMR) and Raman spectroscopies. 31P NMR studies revealed perturbation of the lipid head groups in the presence of the icosapeptide. Simulation of the 31P NMR spectra indicated that the obser...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00347a019
更新日期：1985-12-17 00:00:00
abstract：:The positions of single amino acids in the interhelical loop regions and the C-terminal tail of bacteriorhodopsin (bR) were investigated by X-ray diffraction using site-directed heavy-atom labeling. Since wild-type bR does not contain any cysteines, appropriate cysteine mutants were produced with a unique sulfhydryl g...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971735s
更新日期：1998-07-21 00:00:00
abstract：:Trp151 in the lactose permease of Escherichia coli (LacY) is an important component of the sugar-binding site and the only Trp residue out of six that is in close proximity to the galactopyranoside in the structure (1PV7). The short distance between Trp151 and the sugar is favorable for Förster resonance energy transf...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi061632m
更新日期：2006-12-26 00:00:00
abstract：:Sin3 forms the scaffold for a multiprotein corepressor complex that silences transcription via the action of histone deacetylases. Sin3 is recruited to the DNA by several DNA binding repressors, such as the helix-loop-helix proteins of the Mad family. Here, we elaborate on the Mad-Sin3 interaction based on a binding s...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0355645
更新日期：2004-01-13 00:00:00
abstract：:Vitamin D receptor (VDR) is a member of the nuclear hormone receptor superfamily. When bound to a variety of vitamin D analogues, VDR manifests a wide diversity of physiological actions. The molecular mechanism by which different vitamin D analogues cause specific responses is not understood. The published crystallogr...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi201637p
更新日期：2011-12-27 00:00:00
abstract：:Human melanin-concentrating hormone (hMCH) and many of its analogues are potent but nonspecific ligands for human melanin-concentrating hormone receptors 1 and 2 (hMCH-1R and hMCH-2R). To differentiate between the physiological functions of these receptors, selective antagonists are needed. In this study, analogues of...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0200514
更新日期：2002-05-21 00:00:00
abstract：:The peptidolytic reaction of HIV-1 protease has been investigated by using four oligopeptide substrates, Ac-Ser-Gln-Asn-Tyr-Pro-Val-Val-NH2, Ac-Arg-Ala-Ser-Gln-Asn-Tyr-Pro-Val-Val-NH2, Ac-Ser-Gln-Ser-Tyr-Pro-Val-Val-NH2, and Ac-Arg-Lys-Ile-Leu-Phe-Leu-Asp-Gly-NH2, that resemble two cleavage sites found within the natu...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00098a023
更新日期：1991-08-27 00:00:00
abstract：:Cells that depend on oxygen for survival constantly produce reactive oxygen species that attack DNA to produce a variety of lesions, including single-strand breaks with 3'-blocking groups such as 3'-phosphate and 3'-phosphoglycolate. These 3'-blocking ends prevent the activity of DNA polymerase and are generally remov...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi012213m
更新日期：2002-06-18 00:00:00
abstract：:Illumination of envelope vesicles prepared from Halobacterium halobium cells causes translocation of protons from inside to outside, due to the light-induced cycling of bacteriorhodopsin. This process results in a pH gradient across the membranes, an electrical potential, and the movements of K+ and Na+. The electrica...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00655a017
更新日期：1976-05-18 00:00:00
abstract：:The two key structural features of alpha 2-macroglobulin (alpha 2M) involved in inhibitory caging of proteases are the thiol ester and the bait region. This paper examines the environment of the hydrolyzed thiol ester in methylamine-treated human alpha 2M and the separation between the bait region and the thiol ester ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00408a036
更新日期：1988-04-19 00:00:00
abstract：:Protein tyrosine kinases (PTKs) are important regulators of mammalian cell function and their own activities are tightly regulated. Underlying their tight regulation, all PTKs contain multiple regulatory domains in addition to a catalytic domain. C-terminal Src kinase (Csk) contains a catalytic domain and a regulatory...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi048142j
更新日期：2005-02-08 00:00:00
