Abstract：
:In two recent papers, we reported the effects of several point mutations on the thermodynamics of the thermal unfolding of the lysozyme of phage T4 as determined by differential scanning calorimetry. The mutants studied were R96H [Kitamura, S., & Sturtevant, J.M. (1989) Biochemistry 28, 3788-3792] and T157 replaced by A, E, I, L, N, R, and V [Connelly, P., Ghosaini, L., Hu, C.-Q., Kitamura, S., Tanaka, A., & Sturtevant, J.M. (1991) Biochemistry 30, 1887-1891]. Here we report the results of a similar study of the single mutations A82P, A93P, and G113A and the double mutation C54T:C97A. The three single mutants all show small apparent stabilization at pH 2.5 and 46.2 degrees C (the denaturational temperature of the wild-type protein), amounting to -0.5 +/- 0.4 kcal mol-1 in free energy, whereas the double mutant shows a weak apparent destabilization, +0.8 +/- 0.4 kcal mol-1. As in all our previous studies of mutant proteins, the enthalpy changes produced by these mutations are in general of much larger magnitude than the corresponding free energy changes and frequently of opposite sign.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Hu CQ,Kitamura S,Tanaka A,Sturtevant JMdoi
10.1021/bi00121a009subject
Has Abstractpub_date
1992-02-18 00:00:00pages
1643-7issue
6eissn
0006-2960issn
1520-4995journal_volume
31pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:To probe the details of small amplitude motions in proteins, a dynamical analysis of the orientation fluctuations of two tyrosine side chains in the bovine pancreatic trypsin inhibitor is presented. Detailed results are given for the time history and correlation functions obtained for the ring motion from a molecular ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00573a001
更新日期：1979-03-20 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：:G-protein-coupled receptors (GPCRs) have evolved as highly specialized cellular machinery that can dictate biological outcomes in response to diverse stimuli. Specifically, they induce multiple pathway responses upon structural perturbations induced at local protein sites. GPCRs utilize a concurrent strategy involving...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.9b00884
更新日期：2020-01-28 00:00:00
abstract：:The enzyme phosphoenolpyruvate carboxykinase (PEPCK) catalyzes the reversible conversion of oxalacetate and GTP to phosphoenolpyruvate (PEP), GDP, and CO2. PEPCK from higher organisms is a monomer, specifically requires GTP or ITP, and uses Mn2+ as the activating cation. Currently, there is no crystal structure of GTP...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi011374n
更新日期：2001-09-18 00:00:00
abstract：:Dehydroquinate synthase has been purified 9000-fold from Escherichia coli K-12 (strain MM294). The synthase is encoded by the aroB gene, which is carried by plasmid pLC29-47 from the Carbon-Clarke library. Construction of an appropriate host bearing pLC29-47 results in a strain that produces 20 times more enzyme than ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00314a036
更新日期：1984-09-11 00:00:00
abstract：:Prion diseases are associated with the conversion of the normal prion protein, PrP(C), to the infectious disease form PrP(Sc). Discrimination between these isoforms would significantly enhance diagnosis of these diseases, and it has recently been reported that PrP(Sc) is specifically recognized by the serine protease ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi025676g
更新日期：2002-06-04 00:00:00
abstract：:Analogs of EPSP (4-8) have been prepared, and their activity as substrates for the chorismate synthase from Neurospora crassa has been characterized kinetically. The enzyme appears to show strict discrimination against substitution at the Z-position of the enol ether side chain as well as against substitution at the S...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00251a019
更新日期：1994-11-29 00:00:00
abstract：:The R2 protein of ribonucleotide reductase catalyzes the dioxygen-dependent one-electron oxidation of Tyr122 at a diiron-carboxylate site. Methane monooxygenase and related hydroxylases catalyze hydrocarbon hydroxylation at diiron sites structurally related to the one in R2. In protein R2, the likely reaction site for...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9806403
更新日期：1998-07-28 00:00:00
abstract：:The crystal structure of Pseudomonas putida cytochrome P-450cam in the substrate-free form has been refined at 2.20-A resolution and compared to the substrate-bound form of the enzyme. In the absence of the substrate camphor, the P-450cam heme iron atom is hexacoordinate with the sulfur atom of Cys-357 providing one a...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00366a049
更新日期：1986-09-09 00:00:00
abstract：:CC chemokine receptor 5 (CCR5) is the receptor for several inflammatory chemokines and is a coreceptor for HIV-1. Posttranslational sulfation of tyrosines in the N-terminal regions of chemokine receptors has been shown to be important in the binding affinity for chemokine ligands. In addition, sulfation of CCR5 is cru...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi900285c
更新日期：2009-06-16 00:00:00
abstract：:Pepstatin is a slow and tight-binding inhibitor of pepsin. Preincubating enzyme and inhibitor in H2O and in D2O in the absence of substrate generates an inverse solvent isotope effect of Dk = 0.69 +/- 0.06 on the apparent first-order rate constant for the decay in enzymatic activity. Proton inventory analysis of the i...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00198a032
更新日期：1994-08-16 00:00:00
abstract：:In this study, we have investigated the influence of regions outside the DNA-binding domain of the human glucocorticoid receptor on high-affinity DNA binding. We find that the DNA-binding domain shows a 10-fold lower affinity for a palindromic DNA-binding site than the intact receptor. The N-terminal part of the recep...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00152a047
更新日期：1992-09-22 00:00:00
abstract：:The removal of damaged bases by DNA glycosylases is thought to be effectively irreversible, because of an overall equilibrium that favors hydrolysis over synthesis of the N-glycosyl bond. Surprisingly, human alkyladenine DNA glycosylase (AAG) can make damaged DNA by catalyzing formation of an N-glycosyl bond between 1...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi101380d
更新日期：2010-10-26 00:00:00
abstract：:The primary structure of the J chain from a human Waldenströms IgM protein has been determined using a combination of automated and conventional Edman degradative procedures. Eighty-five percent of the sequence was established with peptides isolated from tryptic digests of carboxyamidomethylated and citraconylated J c...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00635a002
更新日期：1977-08-09 00:00:00
abstract：:The manganese transport regulator (MntR) of Bacillus subtilis is activated by Mn(2+) to repress transcription of genes encoding transporters involved in the uptake of manganese. MntR is also strongly activated by cadmium, both in vivo and in vitro, but it is poorly activated by other metal cations, including calcium a...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0524215
更新日期：2006-03-21 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：:Expression of the PSR132 protein from Dianthus caryophyllus (carnation, clover pink) is induced in response to ethylene production associated with petal senescence, and thus the protein is named petal death protein (PDP). Recent work has established that despite the annotation of PDP in sequence databases as carboxyph...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi051779y
更新日期：2005-12-20 00:00:00
abstract：:The multifunctional proline utilization A (PutA) flavoenzyme from Escherichia coli catalyzes the oxidation of proline to glutamate in two reaction steps using separate proline dehydrogenase (PRODH) and Δ(1)-pyrroline-5-carboxylate (P5C) dehydrogenase domains. Here, the kinetic mechanism of PRODH in PutA is studied by ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi201603f
更新日期：2012-01-10 00:00:00
abstract：:An amino-terminal deletion mutant (residues 1-43) of human apolipoprotein A-I (apo hA-I) has been produced from a bacterial expression system to explore the structural and functional role of these amino acids, encoded by exon 3, in apo hA-I. Lipid binding of apo delta (1-43)A-I and lipid binding of apo hA-I are very s...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi961876e
更新日期：1997-01-14 00:00:00
abstract：:A 15-residue fragment within the major continuous domain of gp120 from HIV-1 that can bind independently to the CD4 receptor has been shown to have the property of behaving as a solvent polarity-dependent conformational switch. The switch behavior (cooperative transition from beta-sheet to helical conformation as a fu...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi952045w
更新日期：1996-01-16 00:00:00
abstract：:The Hsp70-class molecular chaperone HscA interacts specifically with a conserved (99)LPPVK(103) motif of the iron-sulfur cluster scaffold protein IscU. We used a cellulose-bound peptide array to perform single-site saturation substitution of peptide residues corresponding to Glu(98)-Ile(104) of IscU to determine posit...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0606187
更新日期：2006-07-04 00:00:00
abstract：:For expression in Saccharomyces cerevisiae the cDNA of the uncoupling protein (UCP) of brown adipose tissue from hamster has been isolated and used to transform yeast cells. Optimized expression conditions yielded 2% of mitochondrial protein as UCP. UCP was isolated, avoiding copurification of ADP/ATP carrier and pori...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi970513r
更新日期：1997-07-08 00:00:00
abstract：:The individual amide proton exchange rates in Tendamistat at pH 3.0 and 50 degrees C were measured by using two-dimensional 1H nuclear magnetic resonance. Overall, it was found that the distribution of exchange rates along the sequence is dominated by the interstrand hydrogen bonds of the beta-sheet structures. The sl...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00394a030
更新日期：1987-10-06 00:00:00
abstract：:We report the first experimental characterization of the full thermodynamic profile for binding of urea to a native protein. We measured the volumetric parameters of lysozyme at pH 7.0 as a function of urea within a temperature range of 18-45 °C. At neutral pH, lysozyme retains its native conformation between 0 and 8 ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.6b00805
更新日期：2016-11-29 00:00:00
abstract：:To develop molecules capable of directly probing the catechol binding region of the beta(2)-adrenergic receptor (beta(2)AR), novel benzophenone- and fluorenone-based beta(2)AR antagonists were prepared as potential photoaffinity probes. While the benzophenone-containing ligands bound with relatively modest affinity, o...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi001342k
更新日期：2000-10-24 00:00:00
abstract：:Thermostable direct hemolysin (TDH) of Vibrio parahemolyticus is a membrane-damaging pore-forming toxin with potent cytolytic/cytotoxic activity. TDH exists as a tetramer consisting of protomers with a core β-sandwich domain, flanked by an 11-amino acid long N-terminal region (NTR). This NTR could not be modeled in th...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.9b00937
更新日期：2020-02-04 00:00:00
abstract：:During cellular uptake of fluorescently labeled cell-penetrating peptides (CPPs), intense fluorescent signals are commonly observed in the nucleus of the cell, suggesting intracellular CPP relocation and potential binding to the genome of the host. We therefore investigated the interaction of the CPP HIV-1 Tat(47-57) ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi700416h
更新日期：2007-07-10 00:00:00
abstract：:For three prokaryotic enzymes of the xanthine oxidase family, namely quinoline 2-oxidoreductase, quinaldine 4-oxidase, and isoquinoline 1-oxidoreductase, the electron transfer centers were investigated by electron paramagnetic resonance. The enzymes are containing a molybdenum-molybdopterin cytosine dinucleotide cofac...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi970581d
更新日期：1997-08-12 00:00:00
abstract：:Actin, an abundant cytosolic protein in eukaryotic cells, is dependent on the interaction with the chaperonin tail-less complex polypeptide 1 ring complex (TRiC) to fold to the native state. The prokaryotic chaperonin GroEL also binds non-native beta-actin, but is unable to guide beta-actin toward the native state. In...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi700658n
更新日期：2007-11-06 00:00:00
abstract：:IIIGlc is an 18.1-kDa signal-transducing phosphocarrier protein of the phosphoenolpyruvate:glycose phosphotransferase system (PTS) of Escherichia coli. Virtually complete (98%) backbone 1H, 15N, and 13C nuclear magnetic resonance (NMR) signal assignments were determined by using a battery of triple-resonance three-dim...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00105a032
更新日期：1991-10-15 00:00:00
