A photocleavable surfactant for top-down proteomics
Open accessAbstract
We report the identification of a photocleavable anionic surfactant, 4-hexylphenylazosulfonate (Azo), which can be rapidly degraded by ultraviolet irradiation, for top-down proteomics. Azo can effectively solubilize proteins with performance comparable to that of sodium dodecyl sulfate (SDS) and is compatible with mass spectrometry. Azo-aided top-down proteomics enables the solubilization of membrane proteins for comprehensive characterization of post-translational modifications. Moreover, Azo is simple to synthesize and can be used as a general SDS replacement in SDS-polyacrylamide gel electrophoresis.
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- Findingown data
Anionic surfactants Azo, SDS, and MaSDeS solubilize proteins more effectively than the non-ionic surfactant DDM.
“Overall, the anionic surfactants, Azo, SDS, and MaSDeS, are highly effective in solubilizing proteins compared to the non-ionic surfactant, DDM (Fig. 1e,f).”
Quote in the paperSubstantial claim - Findingown data
Palmitoylation was localized to cysteine 36 within the transmembrane region based on unmodified b33 and palmitoylated b38 ions.
“We confidently localized the palmitoylation modification to cysteine 36 within the transmembrane region based on the unmodified b33 ion and the palmitoylated b38 ion (Fig. 2a and Supplementary Fig. 18).”
Quote in the paperSubstantial claim - Findingown data
Azo enabled the first detection and identification of multiple proteoforms of calsarcin-1.
“For example, for the first time, Azo enabled the detection and identification of multiple proteoforms of an important Z-disk protein, calsarcin-1 (Supplementary Fig. 14d).”
Quote in the paperSubstantial claim - Findingnone given
Azo solubilizes proteins as effectively as SDS.
“Azo can effectively solubilize proteins with performance comparable to SDS and is mass spectrometry (MS)-compatible.”
Quote in the paperSubstantial claim - Findingown data
Azo can replace SDS in SDS-PAGE.
“For instance, we have used Azo instead of SDS to perform polyacrylamide gel electrophoresis (PAGE) (Supplementary Fig. 3), demonstrating that Azo could be used as a SDS replacement in SDS-PAGE.”
Quote in the paperNot a substantial claim
- Findingcitation
Azo degrades into 4-hexylphenol, 4-hexylbenzene, nitrogen, and hydrogen sulfate upon UV irradiation.
“We further investigated the photo-degradation kinetics of the Azo dissociating into 4-hexylphenol, 4-hexylbenzene, nitrogen, and hydrogen sulfate14 (Fig 1b) upon irradiation with a 100 W high pressure mercury lamp for 0, 10, 30, 60, 90, and 120 s using UV-Vis spectroscopy (Fig. 1d).”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [14] Bradley, M., Vincent, B., Warren, N., Eastoe, J. & Vesperinas, A. Langmuir 22, 101–105 (2006). source
Not checked in the free run.
- Findingown data
51 proteins with transmembrane domains were identified directly from cardiac tissue.
“Moreover, we confidently identified 46 subunits of the electron transport chain (Supplementary Table 6) and 51 proteins with TMDs (Supplementary Table 7) directly from cardiac tissue.”
Quote in the paperSubstantial claim - Findingown data
Under optimal UV-degradation conditions with organic solvent at low pH, many hydrophobic proteins remained soluble after Azo degradation.
“Under the optimal UV-degradation conditions (which include organic solvent at low pH), many hydrophobic proteins were soluble post Azo-degradation.”
Quote in the paperSubstantial claim - Findingown data
46 subunits of the electron transport chain were identified directly from cardiac tissue.
“Moreover, we confidently identified 46 subunits of the electron transport chain (Supplementary Table 6) and 51 proteins with TMDs (Supplementary Table 7) directly from cardiac tissue.”
Quote in the paperSubstantial claim - Findingown data
All subunits of the endogenous ATP synthase complex were identified with high mass accuracy.
“Notably, all the subunits of the endogenous ATP synthase complex were identified with high mass accuracy (Fig. 2c).”
Quote in the paperSubstantial claim - Findingown data
High molecular weight ATP synthase subunits α and β, above 50 kDa, were detected and identified with Azo.
“Besides the small and intermediate size subunits (< 30 kDa), with the use of Azo, we were able to detect and identify the high molecular weight (> 50 kDa) ATP synthase subunits: ATP synthase α and β (Fig. 2c).”
Quote in the paperSubstantial claim - Findingown data
Azo had minimal effect on qualitative and quantitative analysis of intact proteins in the presence of TCEP or free methionine.
“We also examined the effect of the UV-irradiation on MS analysis of proteins and found that Azo had minimal effect on the qualitative and quantitative analysis of intact proteins in the presence of reducing agent, tris(2-carboxyethyl)phosphine hydrochloride (TCEP), or free methionine (Supplementary Note 4, Supplementary Fig. 6–9).”
Quote in the paperSubstantial claim - Findingnone given
UV irradiation rapidly degrades Azo (4-hexylphenylazosulfonate).
“We report the identification of a photo-cleavable anionic surfactant, 4-hexylphenylazosulfonate (Azo) that can be rapidly degraded upon UV irradiation, for top-down proteomics.”
Quote in the paperSubstantial claim - Findingown data
Western blot analysis confirmed that Azo successfully extracts integral membrane proteins from cardiac tissue.
“Furthermore, a Western blot analysis confirmed the presence of common cardiac membrane proteins in E3(Azo), demonstrating the successful extraction of integral membrane proteins by Azo (Supplementary Fig. 5).”
Quote in the paperSubstantial claim - Findingown data
Adding 0.5% Azo to the extraction buffer drastically improves protein solubilization compared with no surfactant.
“The SDS-PAGE gel (Fig. 1e) and protein assay (Fig. 1f) show that the addition of 0.5% Azo to the extraction buffer, labelled as E3(Azo), drastically improved the solubilization of proteins when compared to the control without surfactant, E3(NS), which barely solubilized proteins after the depletion of soluble proteins using HEPES buffer, E1 and E2.”
Quote in the paperSubstantial claim - Findingown data
Organic solvent and acid facilitate rapid degradation of Azo.
“By comparing several degradation conditions, we found that the presence of organic solvent and acid facilitates rapid degradation of Azo (Supplementary Fig. 4).”
Quote in the paperNot a substantial claim - Findingown data
Azo is compatible with mass spectrometry.
“More importantly, Azo surfactant is MS-compatible.”
Quote in the paperSubstantial claim - Findingreasoning
Azo-aided top-down proteomics enables membrane protein solubilization for comprehensive characterization of post-translational modifications.
“Importantly, Azo-aided top-down proteomics enables the solubilization of membrane proteins for comprehensive characterization of post-translational modifications.”
Quote in the paperSubstantial claim - Findingown data
A total of 2836 proteoforms were detected based on accurate mass measurements from three LC-MS runs.
“Moreover, we have detected a total of 2836 proteoforms based on accurate mass measurements (Supplementary Table 3) from the combination of three LC-MS runs”
Quote in the paperSubstantial claim - Interpretationown data
Azo enables detection and comprehensive characterization of cardiac membrane protein complexes.
“Thus, Azo enables the detection and comprehensive characterization of these important cardiac membrane protein complexes, which opens up new opportunities to uncover their molecular basis in health and disease.”
Quote in the paperSubstantial claim - Premisecitation
Protein solubility is a major challenge in top-down proteomics, especially for membrane proteins.
“One such challenge in top-down proteomics is protein solubility4, especially for membrane proteins, which comprise a large proportion of the proteome and play a critical role in many cellular functions and are important drug targets5,6.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [4] Chen, B., Brown, K. A., Lin, Z. & Ge, Y. Anal. Chem. 90, 110–127 (2018). source
Not checked in the free run.
- Premisecitation
Conventional ionic surfactants are incompatible with mass spectrometry because they greatly suppress protein MS signal.
“Unfortunately, conventional ionic surfactants are not compatible with MS because they greatly suppress protein MS signal6, 7.”
Quote in the paperSubstantial claim0 of 2 sources checked - Interpretationown data
Among evaluated surfactants, Azo is the only strong surfactant that effectively solubilizes proteins, including membrane proteins, without hindering downstream top-down MS analysis.
“Among all the surfactants we have evaluated, we found that 4-hexylphenylazosulfonate (Azo) to be the only strong surfactant capable of effectively solubilizing proteins, including membrane proteins, without hindering downstream top-down MS analysis.”
Quote in the paperSubstantial claim
- May combine two claims. 25
- Classified as probably not a substantial claim. 10
May combine two claims.
Findingown dataIntegral membrane proteins phospholamban, receptor-expressing enhancing protein, and succinate dehydrogenase cytochrome b560 with 1, 2, and 3 transmembrane domains, respectively, were identified.
“Using cardiac tissue as an example, we identified several important integral membrane proteins such as phospholamban (PLN), receptor-expressing enhancing protein, and succinate dehydrogenase cytochrome b560 with 1, 2, and 3 transmembrane domains (TMD), respectively (Fig. 2a,b and Supplementary Fig. 17).”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Findingown dataAzo is simple to synthesize.
“Notably, Azo was simple to synthesize, requiring only two steps (Fig. 1c), and could be effectively purified by recrystallization, making it an ideal candidate for general use as a surfactant in biochemical applications.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Findingown dataThe proton NMR spectrum of Azo displayed signals at chemical shifts of 7.64, 7.37, 2.67-2.48, 1.61, 1.28, and 0.86 ppm with the reported multiplicities and integrations.
“1H NMR: δ 7.64 (2H, dd, -Ar-H), 7.37 (2H, d, -Ar-H), 2.67–2.48 (2H, m,-Ar-CH2), 1.61 (2H, t, -Ar-CH2CH2), 1.28 (6H, t, -(CH2)3) .086 (3H, t, -(CH2)3-CH3).”
Quote in the paperNot a substantial claimMay combine two claims.
Findingown dataAzo improved detection depth and revealed many proteins that were undetectable in the control sample.
“In addition to the breadth in increased protein identifications, Azo also greatly improved the depth of the detection and revealed many proteins that were undetectable in the control sample (Supplementary Fig. 14a–j).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown dataAzo facilitated identification of ATP6 with 6 transmembrane domains and localization of a trimethylation to lysine 43 between 2 transmembrane domains of ATP synthase subunit c.
“In particular, Azo facilitated the identification of ATP6 (also known as ATP synthase subunit a; Mr 24952.55) with 6 TMD as well as the localization of a trimethylation to lysine 43 between 2 TMD of ATP synthase subunit c (Supplementary Fig. 19).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data0.1% DDM and 0.1% Azo yielded comparable MS signals with minimal suppression relative to no surfactant.
“In contrast, 0.1% DDM and 0.1% Azo yielded comparable MS signals, showing minimal signal suppression when compared to the control with no surfactant (Fig. 1g).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown dataAcetylation, methylation, phosphorylation, and palmitoylation were observed.
“Importantly, we have observed various PTMs included acetylation, methylation, phosphorylation, and palmitoylation (Supplementary Table 5–10).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown dataSystematic screening identified Azo as the top-performing surfactant because it is water-soluble and greatly improves protein extraction.
“We performed a systematic screening of many synthesized candidates (Supplementary Note 1–3 and Supplementary Table 1) and identified 4-hexylphenylazosulfonate17 (Fig. 1b and Supplementary Fig. 1–2), hereafter referred to as “Azo”, to be the top-performing surfactant, as it not only is water-soluble, but also greatly improves protein extraction (Supplementary Table 1).”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [17] Dunkin, I. R., Gittinger, A., Sherrington, D. C. & Whittaker, P. J. Chem. Soc. Perkin Trans. I 2, 1837–1842 (1996). source
Not checked in the free run.
May combine two claims.
Findingown dataIn a single RPLC/MS run, 663 unique proteoforms were observed with Azo, compared with 6 without surfactant.
“In a single RPLC/MS run, we observed 663 unique proteoforms in E3(Azo), in contrast to E3(NS) where only 6 unique proteoforms were detected (Supplementary Fig. 13c,d and Supplementary Table 4).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data388 proteoforms were identified by one-dimensional online RPLC-MS/MS, representing 171 proteins from multiple cellular localizations.
“among which 388 proteoforms were identified based on one-dimensional online RPLC-MS/MS data (Supplementary Table 4) representing 171 proteins (Supplementary Table 5) from mitochondria, nucleus, plasma membrane, cytoskeleton, endoplasmic reticulum, cytoplasm, and extracellular region”
Quote in the paperSubstantial claimMay combine two claims.
Findingown dataAzo can extract and enable top-down proteomic analysis of membrane proteins from cardiac tissues and HEK293T cells.
“Because surfactants are beneficial for solubilization of peripheral and integral membrane proteins, we further show that Azo can effectively extract and enable the top-down proteomic analysis of membrane proteins from cardiac tissues (Fig. 2 and Supplementary Fig. 15) as well as human embryonic kidney (HEK) 293T cells (Supplementary Fig. 16 and Supplementary Table 9–10).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown dataReceptor-expressing enhancing protein was characterized, and an acetylation site was localized to its N-terminus.
“Similarly, we have characterized receptor-expressing enhancing protein and localized an acetylation site to the N-terminus (Fig. 2b).”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Findingown dataThe ESI mass spectrum of Azo showed an observed m/z of 269.098 for the [M-Na]− ion, which matched the calculated m/z of 269.096.
“ESI-MS for Azo (C12H17N2O3SNa), [M-Na]−, calculated m/z: 269.096, observed m/z: 269.098.”
Quote in the paperNot a substantial claimMay combine two claims.
Findingown dataCID fragmentation was highly efficient and preferentially cleaved in transmembrane domain portions, leading to confident protein identification and PTM localization.
“We observed highly efficient CID fragmentation which preferentially cleaved in the transmembrane domain portions of the proteins (Fig. 2a,b and Supplementary Fig. 17–19), leading to confident protein identification of these integral membrane proteins and localization of PTMs in online RPLC-MS/MS experiments (Supplementary Table 4–10).”
Quote in the paperSubstantial claimMay combine two claims.
Findingown data0.1% SDS completely suppressed the MS signal, and 0.1% MaSDeS significantly suppressed the MS signal.
“The results showed the presence of 0.1% SDS completely suppressed the MS signal and 0.1% MaSDeS significantly suppressed the MS signal.”
Quote in the paperSubstantial claimMay combine two claims.
Findingown dataIntact unmodified phospholamban and its highly abundant palmitoylated proteoform were detected.
“Notably, we not only detected intact unmodified PLN, but also its highly abundant palmitoylated proteoform (Fig. 2a).”
Quote in the paperSubstantial claimClassified as probably not a substantial claim. May combine two claims.
PremisecitationTop-down mass spectrometry analyzes intact proteins and is the most powerful approach for comprehensive proteoform characterization, including post-translational modifications and sequence variants.
“In contrast, top-down mass spectrometry (MS)-based proteomics analyzes intact proteins and is the most powerful method to comprehensively characterize proteoforms deciphering the PTMs together with sequence variations1–3.”
Quote in the paperSubstantial claim0 of 3 sources checked- cites [1] Aebersold, R. et al. Nat. Chem. Biol. 14, 206–214 (2018). source
Not checked in the free run.
- cites [2] Siuti, N. & Kelleher, N. L. Nat. Methods 4, 817–821 (2007). source
Not checked in the free run.
- cites [3] Cai, W. X., Tucholski, T. M., Gregorich, Z. R. & Ge, Y. Expert Rev. Proteomics 13, 717–730 (2016). source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationA clear 1% solution of Azo has a Krafft temperature of 24.5 °C, as reported in prior work.
“Kraft temperature (a clear 1% surfactant solution) was previously reported at 24.5 °C7.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [7] Loo, R. R., Dales, N. & Andrews, P. C. Protein Sci. 3, 1975–1983 (1994). source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown dataThe protein solubility comparison of Azo, SDS, DDM, and MaSDeS used three independent protein assays, and the error bars represent the standard error of the mean.
“For the protein solubility experiment (Figure 1f) comparing Azo, SDS, DDM, and MaSDeS, three independent protein assays (n=3) were performed to evaluate surfactant performance. Error bars represent standard error of the mean.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown dataFor the LC-MS analysis, three separate samples were prepared for each condition, and the error bars represent the standard error of the mean.
“For LC-MS analysis (Supplementary Fig. 9), three separate samples (n=3) were prepared for each condition. Error bars represent standard error of the mean.”
Quote in the paperNot a substantial claimMay combine two claims.
Interpretationown dataAmong all evaluated surfactants, Azo is the only one that both effectively solubilizes proteins and is compatible with top-down MS analysis of intact proteins.
“We concluded that among all the surfactants evaluated, Azo is the only surfactant that not only can effectively solubilize proteins but also is compatible with top-down MS analysis of intact proteins.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown dataThe broader protein solubility comparison used three independent experiments, and the error bars represent the standard error of the mean.
“For the broader protein solubility comparison (Supplementary Fig. 10), data presented were based on three independent experiments (n=3). Error bars represent standard error of the mean.”
Quote in the paperNot a substantial claimMay combine two claims.
PremisecitationSurfactants must be removed before MS analysis, and this removal can cause protein loss and degradation.
“Therefore, surfactants need to be removed prior to MS analysis, which may result in protein loss and degradation8, 9.”
Quote in the paperSubstantial claim0 of 2 sources checkedProbably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.
InterpretationreasoningBecause Azo can be easily synthesized and purified, it can serve as a cleavable SDS replacement in general biochemical applications such as SDS-PAGE.
“Notably, because Azo can be easily synthesized and purified, it can be used as a cleavable SDS-replacement in general biochemical applications, for example, in SDS-PAGE.”
Quote in the paperNot a substantial claimMay combine two claims.
Interpretationown dataThe study developed a photo-cleavable MS-compatible surfactant that increases protein solubility and enabled a general high-throughput top-down proteomics method.
“In summary, we have developed a photo-cleavable MS-compatible surfactant to increase protein solubility and enabled a general, high-throughput method for top-down proteomics.”
Quote in the paperSubstantial claim- Rests on an assumption: The products formed when Azo degrades are innocuous and non-surfactant.
May combine two claims.
PremisecitationAcid-labile surfactants have been effective for bottom-up proteomics, but none have shown direct compatibility with intact protein MS for top-down proteomics.
“Efforts have been made in developing various acid-labile surfactants which have been effective for bottom-up proteomics10–13, however none have demonstrated direct compatibility with intact protein MS for top-down proteomics.”
Quote in the paperSubstantial claim0 of 4 sources checked- cites [10] Chang, Y.-H. et al. J. Proteome Res. 14, 1587–1599 (2015). source
Not checked in the free run.
- cites [11] Yu, Y. Q., Gilar, M., Lee, P. J., Bouvier, E. S. & Gebler, J. C. Anal. Chem. 75, 6023–6028 (2003). source
Not checked in the free run.
- cites [12] Chen, E. I., Cociorva, D., Norris, J. L. & Yates, J. R. J. Proteome Res. 6, 2529–2538 (2007). source
Not checked in the free run.
- cites [13] Meng, F. et al. Anal. Chem. 74, 2923–2929 (2002). source
Not checked in the free run.
Classified as probably not a substantial claim. May combine two claims.
Study design and conductnone givenProtein identifications were accepted only when they had statistically significant P and E values below 1E-5 and more than six assigned fragment ions.
“All identifications were validated with statistically significant P and E values (<E-5) and satisfactory numbers of assigned fragment ions (>6).”
Quote in the paperSubstantial claimMay combine two claims.
PremisecitationConventional bottom-up proteomics analyzes peptides from protein digests, does not directly identify proteoforms, and is suboptimal for characterizing post-translational modifications and sequence variants.
“The conventional “bottom-up” proteomics analyzes peptides from protein digests which does not directly identify proteoforms and is suboptimal for characterizing PTMs and sequence variants1.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [1] Aebersold, R. et al. Nat. Chem. Biol. 14, 206–214 (2018). source
Not checked in the free run.
The paper relies on this without support.
The products formed when Azo degrades are innocuous and non-surfactant.
“Developing MS-compatible surfactants that can be quickly degraded into innocuous non-surfactant byproducts prior to MS analysis can help address the protein solubility challenge in top-down proteomics.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Brown et al. developed photocleavable ionic surfactant Azo, which has extraction efficiency comparable to SDS and is compatible with top-down MS after rapid UV degradation.
“Brown et al. have recently developed a photocleavable ionic surfactant, 4-hexylphenylazosulfonate (Azo) [31], which shows comparable protein extraction efficiency to common surfactants such as SDS and was compatible with top-down MS analysis after rapid UV-degradation (Figure 2) [31].”
From Top-down proteomics: challenges, innovations, and applications in basic and clinical research (2020) · cites this paper as [31]
Those acid-cleavable surfactants are incompatible with top-down proteomics.
“However, it was found that these surfactants are incompatible with top-down proteomics [31].”
From Top-down proteomics: challenges, innovations, and applications in basic and clinical research (2020) · cites this paper as [31]
Top-down proteomics allows direct analysis of intact proteins without digestion, providing a bird's-eye view of existing proteoforms.
“top-down proteomics allows for direct analysis of intact proteins without digestion, thus providing a “bird’s-eye” view of existing proteoforms (9, 12, 21, 23, 28, 29).”
From Distinct hypertrophic cardiomyopathy genotypes result in convergent sarcomeric proteoform profiles revealed by top-down proteomics (2020) · cites this paper as [29]
A previous study found that DDM, a mild detergent, only marginally improved protein solubility.
“A previous study indicated DDM, which is a mild detergent, only marginally improved protein solubility.24”
From Sensitive Top-Down Proteomics Analysis of a Low Number of Mammalian Cells Using a Nanodroplet Sample Processing Platform (2020) · cites this paper as [24]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Dodecylaniline is mislabeled as C10
MinorThe AZO synthesis labels both decylaniline and dodecylaniline as C10, even though they have different chain lengths. Elsewhere, the paper labels an n=10 dodecyl compound as C12.
“For 4-n-decylaniline (n= 8, C10) and 4-n-dodecylaniline (n= 10, C10)”
“Intermediate product I (n= 10, C12) was obtained as an amorphous white powder.”
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Saveliev, S. V., Woodroofe, C. C., Sabat, G., Adams, C. M., Klaubert, D., Wood, K., & Urh, M. (2013) · Analytical Chemistry · doi:10.1021/ac302423t · Cited by 62 · see citing works
Photoresponsive Surfactants in Microgel Dispersions
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The benefits (and misfortunes) of SDS in top-down proteomics
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Synthesis, characterization and applications of azo-containing photodestructible surfactants
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Syntheses and Activities of New C10 β-Turn Peptidomimetics
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Self-citation
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Top-down proteomics: challenges, innovations, and applications in basic and clinical research
Brown, K. A., Melby, J. A., Roberts, D. S., & Ge, Y. (2020) · Expert Review of Proteomics · doi:10.1080/14789450.2020.1855982 · Cited by 152 · see citing works
Self-citationTucholski, T., Cai, W., Gregorich, Z. R., Bayne, E. F., Mitchell, S. D., McIlwain, S. J., de Lange, W. J., Wrobbel, M., Karp, H., Hite, Z., et al. (2020) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2006764117 · Cited by 107 · see citing works
Self-citationMASH Explorer: A Universal Software Environment for Top-Down Proteomics
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Self-citationNanoproteomics enables proteoform-resolved analysis of low-abundance proteins in human serum
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Self-citationHigh‐Throughput Proteomics Enabled by a Photocleavable Surfactant
Brown, K. A., Tucholski, T., Eken, C., Knott, S., Zhu, Y., Jin, S., & Ge, Y. (2020) · Angewandte Chemie · doi:10.1002/ange.201915374 · Cited by 14 · see citing works
Self-citation
- Authors
- Brown, K. A., Chen, B., Guardado-Alvarez, T. M., Lin, Z., Hwang, L., Ayaz-Guner, S., Jin, S., & Ge, Y.
- Affiliations
- University of Wisconsin–Madison (US)
- Corresponding author
- Ge, Ying
- Venue
- Nature Methods
- Published
- 2019-04-15
- Volume
- 16
- Issue
- 5
- Pages
- 417-420
- ISSN
- 1548-7091 (ISSN-L)
- 1548-7105
- PMC
- PMC6532422
- OpenAlex
- W2938859552
- Cited by
- 111
- References
- 32
- Citations by year
- 2026: 9 · 2025: 11 · 2024: 16 · 2023: 26 · 2022: 13 · 2021: 18 · 2020: 13 · 2019: 5
- FWCI
- 4.88
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Licence
- www.springer.com/tdm (tdm)
- Locations
- Nature Methods (publishedVersion)
- PubMed (publishedVersion)
- Europe PMC (PubMed Central) (acceptedVersion)
- PubMed Central (acceptedVersion)
- Funders
- National Institutes of Health (1s10od018475-01)
- National Heart, Lung, and Blood Institute (R01HL109810, R01HL096971)
- National Institute of General Medical Sciences (R01GM125085, R01GM117058)
- Topics
- Physical Sciences › Chemistry › Spectroscopy › Advanced Proteomics Techniques and Applications
- Physical Sciences › Chemistry › Spectroscopy › Mass Spectrometry Techniques and Applications
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Protein Structure and Dynamics
- Keywords
- top-down proteomics, protein solubilization, membrane protein solubilization, post-translational modification, UV irradiation, SDS-polyacrylamide gel electrophoresis
- MeSH terms
- Azo Compounds, Electrophoresis, Polyacrylamide Gel, Membrane Proteins, Photolysis, Sodium Dodecyl Sulfate, Solubility, Mass Spectrometry, Surface-Active Agents, Ultraviolet Rays, Proteomics, Hydrophobic and Hydrophilic Interactions
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