Abstract:
:We have assayed the cross-linking of oligonucleotides containing repeated mitomycin-reactive CpG sites in order to assess the factors that enhance activation of the carbamoyl function at C10, yielding efficient mitomycin cross-linking. Drugs studied include mitomycin C (MC), N-methylmitomycin A (NMA), and the aziridinomitosene of NMA (MS). Drugs were reduced both by catalytic hydrogenation and by diothionite. We find that cross-linking by fully reduced NMA can be increased severalfold by addition of either excess dithionite reductant or the oxidant FeCl3. Enhancement by FeCl3 is not seen with MC or MS, but excess dithionite increases cross-linking by all three compounds. We explain the action of Fe3+ by postulating production of the semiquinone of the monoadduct of mitomycin reacted at the C1-position; according to this mechanism, departure of the carbamate from C10 is more efficient for the semiquinone than for the hydroquinone. However, our results imply that the hydroquinone can also function as a cross-linking agent. Excess dithionite, beyond that required for stoichiometric reduction, activates the carbamate 2-3-fold for cross-linking. We find that the fully reduced leucoaziridinomitosene is highly unstable in solution, yet it produces efficient cross-liking. Hence, this compound is highly reactive in DNA alkylation and a good candidate for the role of primary alkylating agent.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Cera C,Egbertson M,Teng SP,Crothers DM,Danishefsky SJdoi
10.1021/bi00439a049subject
Has Abstractpub_date
1989-06-27 00:00:00pages
5665-9issue
13eissn
0006-2960issn
1520-4995journal_volume
28pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Pyrroloquinoline quinone (PQQ) is a small, redox active molecule that serves as a cofactor for several bacterial dehydrogenases, introducing pathways for carbon utilization that confer a growth advantage. Early studies had implicated a ribosomally translated peptide as the substrate for PQQ production. This study pres...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi201763d
更新日期:2012-03-20 00:00:00
abstract::Electrogenic events associated with the activity of the melibiose permease (MelB), a transporter from Escherichia coli, were investigated. Proteoliposomes containing purified MelB were adsorbed to a solid supported lipid membrane, activated by a substrate concentration jump, and transient currents were measured. When ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0489053
更新日期:2004-10-05 00:00:00
abstract::The unique structural properties of the ferritin protein cages have provided impetus to focus on the methodical study of these self-assembling nanosystems. Among these proteins, Escherichia coli bacterioferritin (EcBfr), although architecturally very similar to other members of the family, shows structural instability...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi200207w
更新日期:2011-05-17 00:00:00
abstract::We report here that the DNA strand scission by dynemicin A is not only sequence-specific but also conformation-specific. The salt-induced B----Z conformational transition dramatically enhanced the cleavage by dynemicin A in a B-Z junction region. By contrast, the bleomycin-Fe(II) complex, the elsamicin A-Fe(II) comple...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00144a019
更新日期:1992-07-28 00:00:00
abstract::It has been shown by genetic analysis that the external and internal invertases from Saccharomyces cerevisiae share a common structural gene [Taussig, R., & Carlson, M. (1983) Nucleic Acids Res. 11, 1943-1954]. However, the only amino acid composition of these two forms of invertase reported to date has revealed exten...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00343a014
更新日期:1985-10-22 00:00:00
abstract::Characterization of the complete gene sequence encoding the alpha-galactosidase from Phanerochaete chrysosporium confirms that this enzyme is a member of glycosyl hydrolase family 27 [Henrissat, B., and Bairoch, A. (1996) Biochem. J. 316, 695-696]. This family, together with the family 36 alpha-galactosidases, forms g...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0008074
更新日期:2000-08-15 00:00:00
abstract::IFABP is a small beta-barrel protein with a short helix-turn-helix motif near the N-terminus that is thought to participate in the regulation of the uptake and delivery of fatty acids. In a previous work, we detected by near UV circular dichroism a reversible conformational transition of this protein occurring between...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi020680d
更新日期:2003-06-24 00:00:00
abstract::The active site structures of human Q31 granzyme A, murine granzymes (A, B, C, D, E, and F), and human granzymes (A, B, and 3) isolated from cytotoxic T lymphocytes (CTL) were studied with peptide thioester substrates, peptide chloromethyl ketone, and isocoumarin inhibitors. Human Q31, murine, and human granzyme A hyd...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00222a027
更新日期:1991-02-26 00:00:00
abstract::To maintain daily cycles, the circadian clock must tightly regulate the rhythms of thousands of mRNAs and proteins with the correct period, phase, and amplitude to ultimately drive the wide range of rhythmic biological processes. Recent genomic approaches have revolutionized our view of circadian gene expression and h...
journal_title:Biochemistry
pub_type: 杂志文章,评审
doi:10.1021/bi500707c
更新日期:2015-01-20 00:00:00
abstract::A metastable intermediate was found in the course of the denaturation of purified cytochrome P450 2B1 by increasing concentrations of guanidine hydrochloride (GuHCl). The metastable intermediate has no or low absorbance at 450 nm in the reduced carbon monoxide difference spectrum and has no absorbance at 420 nm. The i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00016a023
更新日期:1995-04-25 00:00:00
abstract::The VWF A1 domain seems to possess two heparin binding regions (residues 565-587 and 633-648) displaying positively charged amino acids, but the overall polyanion-A1 domain interaction scheme remains essentially elusive. To probe this molecular reaction as well as the role of electrostatic forces in VWF-heparin intera...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi020044f
更新日期:2002-05-28 00:00:00
abstract::Orthophosphate and phosphate derivatives including pyrophosphate, hexametaphosphate, ATP, ADP, and inositol hexaphosphate enhance the extent of DNA degradation by iron(II) bleomycin. These phosphate-containing compounds increase both the release of free nucleic base and that of base propenals which are DNA cleavage pr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00335a034
更新日期:1985-07-02 00:00:00
abstract::Band 3, the anion transport protein of human erythrocyte membranes, can be transferred from cells to liposomes and from liposomes back to cell membranes, retaining function and native orientation. After incubation with cells, sonicated phosphatidylcholine vesicles bind a transmembrane protein that comigrates with band...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00295a011
更新日期:1983-12-20 00:00:00
abstract::The traditional approach to studying protein folding involves applying a perturbation, usually denaturant or mutation, and determining the effect upon the free energy of folding, DeltaG0, and the activation free energy, DeltaG(not equal). Data collected as a function of the perturbation can be used to construct rate e...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi701645g
更新日期:2007-12-11 00:00:00
abstract::Upon blue light irradiation, photoactive yellow protein (PYP) undergoes a conformational change that involves large movements at the N-terminus of the protein. We reasoned that this conformational change might be used to control other protein or peptide sequences if these were introduced as linkers connecting the N- a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi400018h
更新日期:2013-05-14 00:00:00
abstract::Colicin E3 is a 60 kDa, multidomain protein antibiotic that targets its ribonuclease activity to an essential region of the 16S ribosomal RNA of Escherichia coli. To prevent suicide of the producing cell, synthesis of the toxin is accompanied by the production of a 10 kDa immunity protein (Im3) that binds strongly to ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0273720
更新日期:2003-04-15 00:00:00
abstract::The Escherichia coli L-arabinose-binding protein (ABP) participates as a specific receptor in the transport of L-arabinose, D-fucose, and D-galactose through the periplasmic space. The wild-type protein binds L-arabinose about 40 times more strongly than D-fucose. A mutation of the protein at position 108 (Met-->Leu) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00080a013
更新日期:1993-07-27 00:00:00
abstract::The sucrose (CscB) permease belongs to the oligosaccharide:H(+) symporter family of the Major Facilitator Superfamily and is homologous to the lactose permease from Escherichia coli. Sucrose transport in cells expressing sucrose permease is completely inhibited by N-ethylmaleimide (NEM), suggesting that one or more of...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000124o
更新日期:2000-05-23 00:00:00
abstract::Both activities of the aspartokinase--homoserine I (AK-HSD) of Escherichia coli are inhibited by threonine. Careful threonine binding studies have now been done which have allowed us to distinguish the various effects of threonine on the enzyme. The ultrafiltration technique of H. Paulus ((1969) Anal. Biochem. 32, 101...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00610a014
更新日期:1978-08-22 00:00:00
abstract::We describe the crystal structure of human epidermal-type fatty acid binding protein (E-FABP) that was recently found to be highly upregulated in human psoriatic keratinocytes. To characterize E-FABP with respect to ligand-binding properties and tertiary structure, we cloned the respective cDNA, overexpressed the prot...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi990305u
更新日期:1999-09-21 00:00:00
abstract::Self-assembly of beta-sheet domains resulting in the formation of pathogenic, fibrillar protein aggregates (amyloids) is a characteristic feature of various medical disorders. These include neurodegenerative diseases, such as Alzheimer's, Huntington's, and Creutzfeldt-Jacob's. A significant problem in studying such ag...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi990510+
更新日期:1999-06-29 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::A PS I membrane preparation from a PS II deficient mutant of Synechocystis sp. PCC 6803 (psb DI/DII/C) was investigated by picosecond photovoltage and fluorescence measurements. The photovoltage kinetics show two distinct phases. At low excitation energies the fast phase correlates with the fluorescence decay time con...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00195a001
更新日期:1994-07-26 00:00:00
abstract::Protein farnesyltransferase catalyzes the posttranslational farnesylation of several proteins involved in signal transduction, including Ras, and is a target enzyme for antitumor therapies. Efficient product formation catalyzed by protein farnesyltransferase requires an enzyme-bound zinc cation and high concentrations...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0011781
更新日期:2000-10-10 00:00:00
abstract::Hepatic microsomal cytochrome P-450 from phenobarbital-pretreated rats is destroyed by propyne in a reduced nicotinamide adenine dinucleotide dependent process which also results in vivo in the accumulation of an abnormal green porphyrin. The green porphyrin has been identified by its electronic absorption, mass spect...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00528a033
更新日期:1981-12-08 00:00:00
abstract::Apolipoprotein AIV is one of the principal apolipoproteins synthesized by the rat small intestine. We have cloned a cDNA encoding a portion of preapolipoprotein AIV mRNA. A kinetically fractionated cDNA probe highly enriched for the abundant intestinal mucosal mRNA sequences was used to screen a library of recombinant...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00265a007
更新日期:1982-10-26 00:00:00
abstract::RNA binding proteins play an important role in regulating alternative pre-mRNA splicing and in turn cellular gene expression. Many of these RNA binding proteins occur as gene families with members sharing a high degree of primary structure identity and domain organization yet have tissue-specific expression patterns a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00256
更新日期:2018-07-03 00:00:00
abstract::myo-Inositol (mI) is widely distributed in all domains of life and is important for several cellular functions, including bacterial survival. The enzymes responsible for the bacterial catabolism of mI, encoded in the iol operon, can vary from one organism to another, and these pathways have yet to be fully characteriz...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.0c00539
更新日期:2020-08-18 00:00:00
abstract::The binding of UDP-N-acetylglucosamine (UDPNAG) to the enzyme UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) was studied in the absence and presence of the antibiotic fosfomycin by isothermal titration calorimetry. Fosfomycin binds covalently to MurA in the presence of UDPNAG and also in its absence as demonst...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0107041
更新日期:2001-08-21 00:00:00
abstract::The bifunctional reagent p-[(bromoacetyl)-amino]phenyl arsenoxide (BrCH2CONHPhAsO) in the presence of excess reduced nicotinamide adenine dinucleotide has been shown to cause the irreversible active site directed inactivation of the lipoamide dehydrogenase (E3) component of the pyruvate dehydrogenase multienzyme (PD) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00515a018
更新日期:1981-06-09 00:00:00