Abstract：
:15N NMR spectroscopy was used to examine the active-site histidyl residue of alpha-lytic protease in peptide boronic acid inhibitor complexes. Two distinct types of complexes were observed: (1) Boronic acids that are analogues of substrates form complexes in which the active-site imidazole ring is protonated and both imidazole N-H protons are strongly hydrogen bonded. With the better inhibitors of the class this arrangement is stable over the pH range 4.0-10.5. The results are consistent with a putative tetrahedral intermediate like complex involving a negatively charged, tetrahedral boron atom covalently bonded to O gamma of the active-site serine. (2) Boronic acids that are not substrate analogues form complexes in which N epsilon 2 of the active-site histidine is covalently bonded to the boron atom of the inhibitor. The proton bound to N delta 1 of the histidine in these histidine-boronate adducts remains strongly hydrogen bonded, presumably to the active-site aspartate. Benzeneboronic acid, which falls in this category, forms an adduct with histidine. In both types of complexes the N-H protons of His-57 exchange unusually slowly as evidenced by the room temperature visibility of the low-field 1H resonances and the 15N-H spin couplings. These results, coupled with the kinetic data of the preceding paper [Kettner, C. A., Bone, R., Agard, D. A., & Bachovchin, W. W. (1988) Biochemistry (preceding paper in this issue)], indicate that occupancy of the specificity subsites may be required to fully form the transition-state binding site. The significance of these findings for understanding inhibitor binding and the catalytic mechanism of serine proteases is discussed.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Bachovchin WW,Wong WY,Farr-Jones S,Shenvi AB,Kettner CAdoi
10.1021/bi00420a018subject
Has Abstractpub_date
1988-10-04 00:00:00pages
7689-97issue
20eissn
0006-2960issn
1520-4995journal_volume
27pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:The cyclic antimicrobial lipopeptide daptomycin is now frequently used as a first-line therapy in serious infections caused by multidrug-resistant Enterococcus faecium. Resistance to daptomycin in E. faecium is mediated by activation of the LiaFSR membrane stress response pathway. Deletion of liaR, encoding the respon...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.8b01072
更新日期：2018-12-11 00:00:00
abstract：:Halogen bonding is a weak chemical force that has so far mostly found applications in crystal engineering. Despite its potential for use in drug discovery, as a new molecular tool in the direction of molecular recognition events, it has rarely been assessed in biopolymers. Motivated by this fact, we have developed a p...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.7b00429
更新日期：2017-06-27 00:00:00
abstract：:Mycobacterium tuberculosis and many other members of the Actinomycetes family produce mycothiol, i.e., 1-d-myo-inosityl-2-(N-acetyl-l-cysteinyl)amido-2-deoxy-alpha-d-glucopyranoside (MSH or AcCys-GlcN-Ins), to act against oxidative and antibiotic stress. The biosynthesis of MSH is essential for cell growth and has bee...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi7011492
更新日期：2007-10-09 00:00:00
abstract：:Naturally occurring interruptions in nonfibrillar collagen play key roles in molecular flexibility, collagen degradation, and ligand binding. The structural feature of the interruption sequences and the molecular basis for their functions have not been well studied. Here, we focused on a G5G type natural interruption ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.7b01010
更新日期：2018-02-20 00:00:00
abstract：:Modulation of endogenous gene function, through sequence-specific recognition of double helical DNA via oligonucleotide-directed triplex formation, is a promising approach. Compared to the formation of pyrimidine motif triplexes, which require relatively low pH, purine motif appears to be the most gifted for their sta...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi1012589
更新日期：2011-05-17 00:00:00
abstract：:FTIR-difference spectroscopy in combination with site-directed mutagenesis has been used to investigate the role of water during the photocycle of bacteriorhodopsin. At least one water molecule is detected which undergoes an increase in H-bonding during the primary bR-->K phototransition. Bands due to water appear in ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00209a005
更新日期：1994-11-01 00:00:00
abstract：:The hallmark of serpins is the ability to undergo the so-called "stressed-to-relaxed" switch during which the surface-exposed reactive center loop (RCL) becomes incorporated as strand 4 in central beta-sheet A. RCL insertion drives not only the inhibitory reaction of serpins with their target serine proteases but also...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi100066j
更新日期：2010-05-18 00:00:00
abstract：:Endonuclease V from bacteriophage T4 is a well characterized enzyme that initiates the repair of ultraviolet light induced pyrimidine dimers. Scission of the phosphodiester backbone between the pyrimidines within a dimer, or 3' to an abasic (AP) site, occurs by a beta-elimination mechanism. In addition, high concentra...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00027a031
更新日期：1995-07-11 00:00:00
abstract：:Phospholipase D has been purified 680-fold from an acetone powder of savoy cabbage in an overall yield of 30%. The purification involves solubilization of the acetone powder in a Ca2+-containing buffer and subsequent ammonium sulfate fractionation. Gel filtration on Sephadex G-200 and hydrophobic affinity chromatograp...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00591a014
更新日期：1979-11-27 00:00:00
abstract：:The E-domain of staphylococcal protein A is one of five homologous IgG-binding domains designated E, D, A, B, and C that comprise the extracellular portion of protein A. The E-domain binds tightly to Fc fragments of IgG and binds certain Fv fragments with micromolar affinity. To explore further the structural features...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi961409x
更新日期：1996-12-03 00:00:00
abstract：:Miniproteins reduce the complexity of the protein-folding problem allowing systematic studies of contributions to protein folding and stabilization. Here, we describe the rational redesign of a miniprotein, PPα, comprising a polyproline II helix, a loop, and an α helix. The redesign provides a de novo framework for in...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.9b00067
更新日期：2019-07-16 00:00:00
abstract：:The bacterial second messenger signaling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) controls important biological processes such as biofilm formation, virulence response, and motility. This second messenger is sensed by macromolecular targets inside the cell, both protein and RNA, which ind...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi301510v
更新日期：2013-01-15 00:00:00
abstract：:The water-oxidizing complex of photosystem II cycles through five oxidation states, denoted S(i)() (i = 0-4), during water oxidation to molecular oxygen, which appears at the (transient) S(4) state. The recent detection of bimodal EPR signals from the S(3) state [Matsukawa, T., Mino, H., Yoneda, D., Kawamori, A. (1999...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0159938
更新日期：2002-07-30 00:00:00
abstract：:Photosensitized oxidation reactions damage tissue by catalyzing the formation of oxyradicals and singlet oxygen. beta-Carotene is hypothesized to exert photoprotective effects by quenching singlet oxygen formed by Type II reactions and by scavenging free radicals formed by Type I reactions. beta-Carotene antioxidant m...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9708646
更新日期：1997-10-21 00:00:00
abstract：:Compartmentation and NMR visibility of mitochondrial adenine nucleotides were quantitated in isolated rat liver mitochondria respiring on succinate and glutamate in vitro at 8 and 25 degrees C. Intra- and extramitochondrial nucleotides were discriminated by adding the chelator trans-1,2-diaminocyclohexane-N,N,N',N'-te...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00436a030
更新日期：1989-05-16 00:00:00
abstract：:Apamin is being studied as a model for the folding mechanism of proteins whose structures are stabilized by disulfide bonds. Apamin consists of 18 amino acid residues and forms a stable structure consisting of a C-terminal alpha-helix and two reverse turns. This structure is stabilized by two disulfide bonds connectin...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00133a009
更新日期：1992-05-12 00:00:00
abstract：:Binding of coated vesicle assembly proteins to clathrin causes it to assemble into regular coat structures. The assembly protein fraction of bovine brain coated vesicles comprises AP180, auxilin, and HA1 and HA2 adaptors. Clathrin heavy chains, separated from their light chains, polymerize with unimpaired efficiency w...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00101a027
更新日期：1991-09-17 00:00:00
abstract：:The aminoglycoside 6'-N-acetyltransferase AAC(6')-Ii from Enterococcus faecium is an important microbial resistance determinant and a member of the GCN5-related N-acetyltransferase (GNAT) superfamily. We report here the further characterization of this enzyme in terms of the kinetic mechanism of acetyl transfer and id...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi034148h
更新日期：2003-06-03 00:00:00
abstract：:Three mutants, Asp55-Gly, Tyr306-->Phe, and Asp309-->Asn, of Aspergillus awamori glucoamylase (identical to Aspergillus niger glucoamylase) were constructed to elucidate the roles of two conserved regions within fungal glucoamylases. Kinetic studies indicate that both of these regions are closely associated with activ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00055a017
更新日期：1993-02-02 00:00:00
abstract：:R67 dihydrofolate reductase (DHFR) is an R-plasmid encoded enzyme that confers resistance to the antibacterial drug trimethoprim. This enzyme is not homologous in sequence or structure to chromosomal DHFRs. Equilibrium folding of tetrameric R67 DHFR was studied and found to be fully reversible. Formation of an inactiv...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00180a018
更新日期：1994-04-12 00:00:00
abstract：:Human chorionic gonadotropin (hCG) is a heterodimeric glycoprotein hormone involved in the maintenance of the corpus luteum in early pregnancy. The free alpha-subunit of hCG has a biological activity of its own, namely, stimulation of prolactin secretion from term pregnancy decidual cells [Blithe, D. L., et al. (1991)...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9718548
更新日期：1998-02-17 00:00:00
abstract：:A single G3:U70 base pair in the acceptor helix is the major determinant of alanine acceptance in alanine transfer RNAs. Transfer of this base pair into other transfer RNAs confers alanine acceptance. A G3:C70 substitution eliminates alanine acceptance in vivo and in vitro. In this work, a population of mutagenized G3...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00157a019
更新日期：1992-10-27 00:00:00
abstract：:Binding of substrate to ornithine 4,5-aminomutase (OAM) and methylmalonyl-CoA mutase (MCM) leads to the formation of an electrostatic interaction between a conserved glutamate side chain and the adenosyl ribose of the adenosylcobalamin (AdoCbl) cofactor. The contribution of this residue (Glu338 in OAM from Clostridium...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi3012719
更新日期：2013-02-05 00:00:00
abstract：:Much interest has centered on two surface loops in the motor domain to explain the differences in enzymatic and mechanical properties of myosin isoforms. We showed that two invariant lysines at the C-terminal end of loop 2, which is part of the actin-binding interface, are required to obtain actin activation [Joel et ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi034415j
更新日期：2003-08-05 00:00:00
abstract：:Mercuric reductase, a flavoprotein disulfide oxidoreductase, catalyzes the two-electron reduction of Hg(II) to Hg(0) by NADPH. As with all the members of this class of proteins, the enzyme is a dimer of identical subunits with two active sites per dimer, each composed of one FAD and catalytically essential residues fr...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00224a006
更新日期：1991-03-12 00:00:00
abstract：:Nucleic acid aptamers are rapidly gaining prominence as diagnostic tools, targeting reagents, and potential therapeutics. To extend the use of aptamers into the biochemical analysis of protein interactions on the surface of live cells, we converted an enzymatically generated RNA aptamer into a photo-cross-linkable aff...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi8004208
更新日期：2008-11-18 00:00:00
abstract：:Esterification of retinol (vitamin A alcohol) with long-chain fatty acids by lecithin-retinol acyltransferase (LRAT) is an important step in both the absorption and storage of vitamin A. Retinol in cells is bound by either cellular retinol binding protein (CRBP), present in most tissues including liver, or cellular re...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00144a014
更新日期：1992-07-28 00:00:00
abstract：:The diazomethyl ketones of z-Phe-Phe inactivate papain by a stoichiometric reaction at the active-center thiol. Since the reagents are stable in mercaptoethanol, their reaction with papain is judged to be the result of complex formation characteristic of affinity-labeling reagents. The diazomethyl ketones react by a m...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00645a033
更新日期：1977-12-27 00:00:00
abstract：:The last gene in the nuo operon of Escherichia coli, nuoN, encodes a membrane-bound subunit of Complex I (NADH:ubiquinone oxidoreductase). In this report, the gene for subunit N was disrupted by a 163 bp deletion in the chromosome, resulting in the loss of Complex I function, as measured by deamino-NADH oxidase activi...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0340346
更新日期：2003-05-06 00:00:00
abstract：:The majority of pre-steady-state kinetic investigations with HIV-1 reverse transcriptase (HIV-1 RT) have reported substoichiometric bursts (30-50%) of product formation in the initial reaction cycle. By using quantitative amino acid analysis, we have revised the extinction coefficient of the HIV-1 RT heterodimer and s...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi982163u
更新日期：1999-04-13 00:00:00
