Effect of Cysteic Acid Position on the Negative Ion Fragmentation of Proteolytic Derived Peptides

Williams, Brad J.; Kmiec, Kevin L.; Russell, William K.; Russell, David H.

doi:10.1007/s13361-010-0009-4

Cited by 3 publications

(3 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additionally, the spectrum shows an extensive series of N-terminal ions including a complete series of d ions (d 2 to d 9 ), extensive a, b, and c type ions and a b 7 +H 2 O ion. These observations are similar to those made previously for the negative mode fragmentation of the Nterminal cysteic acid Cys-kemptide (C ox LRRASLG) [23]. The retention of charge at the N-terminus points to a model in which the cysteic acid acts primarily as a fixed charge spectator, thus product ion formation is dominated by charge remote processes.…”

Section: Resultssupporting

confidence: 88%

“…Additionally, preferential cleavage of the amide bond on the C-terminal side of acidic residues are particularly prominent in the case of cysteine sulfinic acid [22]. We recently reported the TOF-TOF CID spectra for peptides containing an N-terminal cysteic acid, finding extensive formation of d type ions from residues containing a cleavable β-γ carbon-carbon bond [23]. Here we extend these investigations to several cysteic acid containing peptides in the negative ion mode in the hope of better understanding the influence of this highly acidic residue on the gas-phase fragmentation observed.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Negative Ion Fragmentation of Cysteic Acid Containing Peptides: Cysteic Acid as a Fixed Negative Charge

Williams

Barlow

Kmiec

et al. 2011

J. Am. Soc. Mass Spectrom.

Self Cite

View full text Add to dashboard Cite

We present here a study of the collision induced dissociation (CID) of deprotonated cysteic acid containing peptides produced by MALDI. The effect of cysteic acid (C ox ) position is interrogated by considering the positional isomers, C ox LVINVLSQG, LVINVLSQGC ox , and LVINVC ox LSQG. Although considerable variation between the CID spectra is observed, the mechanistic picture that emerges involves charge retention at the deprotonated cysteic acid side chain. Fragmentation occurs in the proximity of the cysteic acid group by charge directed mechanisms as well as remote from this group to form ions, which may be rationalized by charge remote mechanisms. Additionally, the formation of the SO 3 -• ion is observed in all cases. Fragmentation of C ox LVINVLSQC ox provides both N-and C-terminal, y and b ions, respectively indicating that the negative charge may be retained at either of the cysteic acids; however, there is some evidence that charge retention at the C-terminal cysteic acid may be preferred. Fragmentation of tryptic type peptides containing a C-terminal arginine or lysine residue is considered through comparison of three peptides C ox LVINKLSQG, C ox LVINVLSQK, and C ox LVINVLSQR. Lastly, we rationalize the formation of b n-1 +H 2 O and a n-1 ions through a mechanism involving rearrangement of the C-terminal residue to form a mixed anhydride intermediate.

show abstract

Section: Resultssupporting

confidence: 88%

Section: Introductionmentioning

confidence: 99%

Negative Ion Fragmentation of Cysteic Acid Containing Peptides: Cysteic Acid as a Fixed Negative Charge

Williams

Barlow

Kmiec

et al. 2011

J. Am. Soc. Mass Spectrom.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Usually, oxidation of disulfides to cysteic acid requires harsh conditions, such as concentrated performic acid. 57 Cysteic acid formation likely deactivates catalysis by neutralizing the catalytically relevant Fe III -OH moiety, 54 as evidenced by the fact that additional equivalents of H2O2 do not further increase yield of cyclohexane oxidation (Table S22). This observation pinpoints the disulfide motif as a weak link and will guide the evolution of future design towards other peptide dimerization techniques.…”

mentioning

confidence: 99%

Rapid, modular secondary sphere assembly for enhanced Fe-catalyzed C(sp3)–H oxidation

Ghosh

Tran

McElheney

et al. 2021

Preprint

View full text Add to dashboard Cite

The inert nature of C(sp3)–H bonds makes their oxidative cleavage a difficult task. While metalloenzymes employ an array of non-covalent interactions to facilitate C(sp3)–H oxidation, this strategy is underexplored in abiotic catalysts due to time-consuming and low-yielding ligand syntheses, which impedes iterative design. To surmount these obstacles, we, herein, have developed a highly modular and rapid synthetic strategy that capitalizes on the efficiency of solid-phase peptide synthesis, which enables the generation of a ligand platform displaying at least four unique residues of varying electronics and sterics in the secondary coordination sphere of a C–H oxidizing Fe catalyst. Modulating the non-covalent interactions in seven variants significantly influences cyclohexane oxidation catalysis, with one variant that boosts the catalytic activity by more than two-fold. To better understand the catalytic trends, we have determined the catalysts’ solution-state structures by 2D NMR spectroscopy, which suggests that peptide conformation can control substrate access and binding. This work demonstrates that (1) tunable, diverse, and complex active sites can be made readily, and (2) these active sites can be optimized to significantly increase catalytic activity.

show abstract

Rapid, modular secondary sphere assembly for enhanced Fe-catalyzed C(sp3)–H oxidation

Ghosh

Tran

McElheney

et al. 2021

Preprint

View full text Add to dashboard Cite

The inert nature of C(sp 3 )-H bonds makes their oxidative cleavage a difficult task. While metalloenzymes employ an array of non-covalent interactions to facilitate C(sp 3 )-H oxidation, this strategy is underexplored in abiotic catalysts due to time-consuming and lowyielding ligand syntheses, which impedes iterative design. To surmount these obstacles, we, herein, have developed a highly modular and rapid synthetic strategy that capitalizes on the efficiency of solid-phase peptide synthesis, which enables the generation of a ligand platform displaying at least four unique residues of varying electronics and sterics in the secondary coordination sphere of a C-H oxidizing Fe catalyst. Modulating the non-covalent interactions in seven variants significantly influences cyclohexane oxidation catalysis, with one variant that boosts the catalytic activity by more than two-fold. To better understand the catalytic trends, we have determined the catalysts' solution-state structures by 2D NMR spectroscopy, which suggests that peptide conformation can control substrate access and binding. This work demonstrates that (1) tunable, diverse, and complex active sites can be made readily, and (2) these active sites can be optimized to significantly increase catalytic activity.

show abstract

Effect of Cysteic Acid Position on the Negative Ion Fragmentation of Proteolytic Derived Peptides

Cited by 3 publications

References 34 publications

Negative Ion Fragmentation of Cysteic Acid Containing Peptides: Cysteic Acid as a Fixed Negative Charge

Negative Ion Fragmentation of Cysteic Acid Containing Peptides: Cysteic Acid as a Fixed Negative Charge

Rapid, modular secondary sphere assembly for enhanced Fe-catalyzed C(sp3)–H oxidation

Rapid, modular secondary sphere assembly for enhanced Fe-catalyzed C(sp3)–H oxidation

Contact Info

Product

Resources

About