Electron transfer versus proton transfer in gasphase ion. Proton transfer and the mobilities of the h and oh ions. Similar to electron capture dissociation, etd induces fragmentation of large, multiplycharged cations by transferring electrons to them. Hammesschiffer and soudackov, jpc b 112, 14108 2008. Similar to electroncapture dissociation, etd induces fragmentation of large, multiplycharged cations by transferring electrons to them. Silbey department of chemistry, massachusetts institute of technology, cambridge, massachusetts 029 received 15 november 1994. Thus the overall rate constant for electron transfer in the activated case ka depends on distance between the participants. Protoncoupled electron transfer sharon hammesschiffer pennsylvania state university note. View enhanced pdf access article on wiley online library html view download pdf for offline viewing. How to merge pdfs and combine pdf files adobe acrobat dc. Here are links to additional resources that might be useful in interpreting etd spectra. Data were collected with and without simultaneous ion trap collisional excitation of the first generation chargereduced product during the ionion. Online pdf converter edit, rotate and compress pdf files.
Etd capability can be added to many thermo scientific ion trap and orbitrap mass spectrometers. Optimization of electron transfer dissociation via. Assess the utility of different dissociation techniques for phosphorylation site analysis of human kinases. In simple terms, an electron transfer reaction involves the transfer of an clcctron from a donor to an acceptor. Chapter 1 introduction to charge transfer and charge transport. Electrontransfer dissociation etd is a method of fragmenting multiplycharged gaseous macromolecules in a mass spectrometer between the stages of tandem mass spectrometry msms. Determination of heterogeneous electron transfer rate. One can calculate the energy needed to assemble an electron due, essentially, to the interaction of the electron with its own field.
We consider photoinduced electron transfer, which is intrinsically a threestate system consisting of. Implementation of electrontransfer dissociation on a. Electron transfer dissociation etd occurs only when proper formation of the fluoranthene anion reagent is achieved. Electron transfer dissociation of peptide anions sciencedirect. An electronrich species willing to part with an electron can give one away to an electronpoor molecule. Subsequently, the resulting remote carboncentered radicals formed by cc cleavage merge with the nickel catalytic cycle to create the challenging csp3csp2 bonds. Recently our laboratory described electron transfer reactions of multiply protonated peptide cations with singly charged polynuclear aromatic anions to induce extensive peptide backbone fragmentation, electron transfer dissociation etd 1, 2. Reid, department of chemistry, marquette university, milwaukee, wisconsin 53233, united states department of chemistry, missouri university of science and technology, rolla, missouri 65409. Chapter 1 basic operation and maintenance this chapter describes basic operation and maintenance of the etd source. The negative mode proteome with activated ion negative electron transfer dissociation nicholas m. The dissociation of the bond may follow or be concerted to the et itself, as. Acceptor complexes of ethylene with molecular and atomic iodine aimable kalume, lisa george, andrew d. The solvation coordinate u is defined as ll e \i 1 \i x. Reid, department of chemistry, marquette university, milwaukee, wisconsin 53233, united states.
Surfaceinduced dissociation of small molecules, peptides, and noncovalent protein complexes vicki h. Chapter 11 electron transfer reactions and electrochemistry introduction redox, or electron transfer, reactions constitute one of the broadest and most important classes of reactions in chemistry. On the dissociation efficiency of charge transfer excitons. If br is small for a given rda, then the interaction is large and electron transfer occurs effectively. Fundamentals of electron capture dissociation fourier. Since its discovery in 1998, electron capture dissociation ecd has been broadly applied to the structural characterization of a wide variety of biomolecules, including proteinspeptides, dnasrnas, carbohydrates, lipids, and protein complexes. Switching between cation and reagent anion injection schemes is automated and accomplished within. Structural characterization of proteins in the gas phase is becoming increasingly popular, highlighting the need for a greater understanding of how proteins behave in the absence of solvent. Introduction electron transfer reactions are of fundanental importance to both chemistry and bioloby. The objective of optimizing the fluoranthene anion is to maximize the abundance of mz 202 while maintaining adequate resolution of mz 203. The negative mode proteome with activated ion negative.
Aug 28, 2015 electron transfer dissociation is a popular peptide fragmentation technique in mass spectrometry. The role of electron transfer dissociation in modern. Chargedependent dissociation of insulin cations via ionion. Yet the bulk of industry consolidation still lies ahead.
Chapter 11 electron transfer reactions and electrochemistry. Beardsley department of chemistry, university of arizona, tucson, arizona, usa this article provides a perspective on collisions of ions with surfaces, including surface. Jun 29, 2004 six years ago, mclafferty and coworkers introduced a unique method for peptideprotein ion fragmentation. However, investigations to determine heterogeneous electron transfer rate constants on iridium, especially at an electron beam evaporated or dc magnetron sputtered surface, have not previously been performed. In this work we study the important contribution to this field dependence due to the dissociation efficiency of the weakly bound interfacial charge transfer ct state, crucial for organic bulk heterojunction solar cells. Photoinduced electron transfer in donor acceptor complexes. Transferring an electron causes peptide backbone cleavage into c and zions. Hornshaw1 and nick morrice2 1thermo fisher scientific, hemel hempstead, uk and 2mrc protein phosphorylation unit, dundee, uk. We show that these sites can be revealed by photoinduced electron transfer dissociation, which produces characteristic c and z ions only if zwitterionic species are present. Start studying group 1a ions, group 2a ions, group 3a ions, group 4a ions, group 5a ions, group 6a ions, group 7a ions. Etd is defined as electron transfer dissociation frequently. Chapter 1 introduction to charge transfer and charge. Hunt lab, department of chemistry, university of virginia.
Group 1a ions, group 2a ions, group 3a ions, group. The net charge for a gaseous ion is easily identified by mass spectrometry, but the presence of zwitterionic pairs or salt bridges has previously been more difficult to detect. Free web app to quickly and easily combine multiple files into one pdf online. Remote nickelcatalyzed crosscoupling arylation via. This paper compares the results of these microfabricated surfacesusing ultramicroelectrode arrays and steadystate currents. Optimization of electron transfer dissociation via informed selection of reagents and operating parameters philip d. Edit your pdf file online and for free with this high quality converter or compress, merge, split, rotate, sort or protect your pdf documents. Pdf merge combine pdf files free tool to merge pdf online. Soda pdf is the solution for users looking to merge multiple files into a single pdf document. Mass spectrometry has rapidly evolved to become the platform of choice for proteomic analysis. Make flashcardsnotecards for your textbooks with this free edtech tool.
The proton transfer reaction mainly reduced the charge of the peptide eq 1, with only a small amount of fragmentation, co 2 loss. Lecture 19, factors determining rates of electron transfer. Unlike a monatomic ion, polyatomic ion composed of more than one atom. Why does n have a higher bond dissociation energy than n2. Electrostatic interactions involving the extreme c. This introductory chapter details basic electron transfer theory and describes some. Electrontransfer dissociation etd is a variation of ecd, in which an ionion reaction, for example, between an anthracene anion and a multiprotonated peptide cation, is used to transfer an electron to the peptide ion.
The purified flagppargamma2 from 293t cells and ppargamma1 protein from caco2 cells were cut from the colloidal bluestained gel, ingel digested with trypsin, and subjected to analysis by lcmsms using a combination of collisioninduced dissociation cid and. Nov 22, 2010 the field dependence of photocurrent found in many organic solar cells is a significant and detrimental setback for internal quantum efficiency. Is the system best represented by a single step transfer or a multistep transport process. The stacking of these reactants and the intervening base pairs, both statically and dynamically. The effect of charge state on the dissociation of polypeptides upon electron transfer from a radical anion was investigated by reacting azobenzene anions with different charge states of peptides including tryptic peptides of myoglobin, model peptides, and peptides of relatively large size. Surfaceinduced dissociation of small molecules, peptides. Difference of electron capture and transfer dissociation. Electron transfer reactions can occur both tliennally and pliotochcnically. Browse or search notecards flashcards easy notecards. Electron transfer dissociation etd is a method of fragmenting multiplycharged gaseous macromolecules in a mass spectrometer between the stages of tandem mass spectrometry msms. In particular, in part ii we presented selfconsistent solutions of the transfer equation for the radiation intensity zn and the kinetic equation for the distribution function of excited atoms fv. Much of this information, along with more details, additional rate constant expressions, and full references to the original papers, is available in the following jpc feature article.
New ion fragmentation technologieselectron capture dissociation ecd and electrontransfer dissociation etdare based on interaction of multiply charged polypeptides with either free electrons ecd or anionic species etd. If both molecules begin with an even number of electrons, the transfer of one electron makes both products odd electron species radicals. Demonstrate electron transfer between atoms to form ionic bonds. An electron rich species willing to part with an electron can give one away to an electron poor molecule. Optimization of electron transfer dissociation via informed. We describe the adaptation of a hybrid quadrupole linear ion trap.
If both molecules begin with an even number of electrons, the transfer of one electron makes both. Many of the ions that form have eight electrons in their valence shell. The new era of proteomics has focused on throughput, sampling depth, and reproducibility, often relying on traditional collisionbased. A free and open source software to merge, split, rotate and extract pages from pdf files. Etd capability can be added to many thermo scientific ion. All reactions that involve molecular oxygen, such as combustion and. The method utilizes pulsed, dual electrospray ion sources and requires minimal instrument modification.
Electron transfer dissociation etd user guide 3 in this guide this guide provides information about your etd source. For reaction centers and the bc 1 complex, a major fraction of the electron transfer distance across the insulating phase is contributed by the conjugate systems. Easily combine multiple files into one pdf document. In this method, multiply protonated peptides or proteins are confined in the penning trap of a fourier transform ion cyclotron resonance fticr mass spectrometer and exposed to electrons with nearthermal energies. Rasaiah2,b 1department of chemistry, kyungsung university, pusan 608736, south korea 2department of chemistry, university of maine, orono, maine 04469, usa. Electron capturetransfer versus collisionally activated. Tandem mass spectrometry, also known as msms or ms 2, is a technique in instrumental analysis where two or more mass analyzers are coupled together using an additional reaction step to increase their abilities to analyse chemical samples. L motif, where l is an electronegative ligand f, oh, och 3, cch, etc. The current crosscoupling proceeds with the generation of an alkoxy radical utilizing bond dissociation free energy bdfe as the thermodynamic driving force. Peptide and protein sequence analysis by electron transfer. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Electron transfer dissociation how is electron transfer. The tutorial is designed to teach you how to interpret and identify etd spectra manually.
Terms in this set 2 how do polyatomic ions differ from monatomic ions. The sample, usually in solution, is first ionized by electrospray. Hornshaw1 and nick morrice2 1thermo fisher scientific, hemel hempstead, uk and 2mrc protein phosphorylation unit, dundee, uk overview purpose. In the nearly 15 years since electron transfer dissociation etd was introduced, bioanalytical mass spectrometry ms and msdriven proteomics have continued to develop as the premier tools for characterizing proteome composition, structure, and function. In a sense, etd is the ionion analog of electron capture dissociation the reagent anion is simply a vehicle for electron delivery.
Comprehensive comparison of collision induced dissociation. For reagent anions in reactions with protonated peptides, proton transfer is usually significantly more exothermic than electron transfer. In coulombic energy transfer no electrons change molecules, but rather two transitions occur simultaneously in a process that could be described as the transfer of a virtual photon. Electron transfer dissociation is a popular peptide fragmentation technique in mass spectrometry. Electron transfer dissociation etd is a recently introduced mass spectrometric technique which has proven to be an excellent tool for the elucidation of labile posttranslational modifications such as phosphorylation and oglcnacylation of serine and threonine residues. Chargedependent dissociation of insulin cations via ion.
Electrostatic interactions involving the extreme c terminus of nuclear export factor. Proton transfer and the mobilities of the h and oh ions from. Electron transfer dissociation and multistage activation analysis of human kinase sites of phosphorylation martin p. The dissociation reactions of various charge states of insulin cations obtained directly from nanoelectrospray were investigated as a result of ionion electron transfer from azobenzene anions. Photoinduced electron transfer in donor acceptor complexes of. All the files you upload as well as merged pdf will be deleted permanently within a few minutes. Nonequilibrium photoinduced electron transfer minhaeng cho and robert j. It requires multiplycharged gasphase cations z2 and therefore it is typically limited to an electron spray ion source. Topdown charge transfer dissociation ctd of gasphase. Singly charged anthracene anions transfer an electron to multiply protonated peptides in a radio frequency quadrupole linear ion trap qlt and induce fragmentation of the peptide backbone along pathways that are analogous to those observed in electron capture dissociation. Electron capture dissociation ecd and electron transfer dissociation etd in metalpeptide complexes are dependent on the metal cation in the complex. While cid remains the major fragmentation method for peptide sequencing, electron transfer dissociation etd is emerging as a complementary method for characterization of peptides and posttranslational modifications ptms.
Electron self energy corrections if one calculates the energy of a point charge using classical electromagnetism, the result is infinite, yet as far as we know, the electron is point charge. Our pdf merger allows you to quickly combine multiple pdf files into one single pdf document, in just a few clicks. Electron transfer dissociation mass spectrometry in proteomics. Over what molecular distance is transport feasible. In this situation, the timedependent electron transfer rate increases in time until the wave packet reaches its thermal equilibrium on the donor potential surface. To study proton transfer reactions of peptide anions, we introduced another cationprotonated fluoranthene. Electron transfer dissociation etd of peptides containing intrachain disulfide bonds article pdf available in journal of the american society for mass spectrometry 232. The benefits of the born effect and of participation of large conjugate ring structures in electron transfer are dependent on the quantummechanical properties of the electron.
Dectris, and the sample to the detector distance was 2. Etd is used extensively with polymers and biological molecules such as proteins and peptides for sequence analysis. Photoelectron transfer dissociation reveals surprising. Peptide sequence analysis by etd mass spectrometry. Welcome to professor donald hunts tutorial on peptide sequence analysis by electron transfer dissociation etd mass spectrometry. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Since no electrons are actually transferred in the coulombic mechanism, it is clear that this process cannot have an analogy in the case of electron transfer. Bond dissociation energy is directly proportional to bond order of a. It is clear that charged residues exert significant influence over structures in the gas phase due to strong coulombic and hydrogenbonding interactions. Electron transfer dissociation is a supremely useful tool for the analysis of posttranslationally modified proteins. Electrontransfer dissociation is a method of fragmenting multiplycharged gaseous macromolecules in a mass spectrometer between the stages of tandem mass spectrometry. In contrast, the etd spectrum displays a rich fragmentation pattern of c and z ions that reveals the exact location of the phosphorylation t. Electron transfer dissociation and multistage activation. A common use of tandemms is the analysis of biomolecules, such as proteins and peptides the molecules of a given sample are ionized and the first.
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