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Selective Metabolite and Peptide Capture/Mass Detection Using Fluorous Affinity Tags

Eden P. Go, Wilasinee Uritboonthai, Junefredo V. Apon, Sunia A. Trauger, Anders Nordstrom, Grace O'Maille, Scott M. Brittain, Eric C. Peters, Gary Siuzdak
2007 Journal of Proteome Research  
The capillary voltage was set at 2.8 kV and the cone voltage at 25 V. The collision energy was set at 16 V. Safety Considerations.  ...  Tryptic peptides were recovered by repeated extraction (3×) with 80% acetonitrile/0.2% TFA (v/v). The peptide extracts were combined then dried in vacuo.  ... 
doi:10.1021/pr060608s pmid:17343404 pmcid:PMC2530906 fatcat:3riaesyd6re6blasfqndjsbjny

Microbial metalloproteomes are largely uncharacterized

Aleksandar Cvetkovic, Angeli Lal Menon, Michael P. Thorgersen, Joseph W. Scott, Farris L. Poole II, Francis E. Jenney Jr, W. Andrew Lancaster, Jeremy L. Praissman, Saratchandra Shanmukh, Brian J. Vaccaro, Sunia A. Trauger, Ewa Kalisiak (+5 others)
2010 Nature  
The peptides were eluted with 1 ml of a saturated solution of a-cyano-4-hydroxycinnamic acid (Sigma-Aldrich) dissolved in 50% (v/v) acetonitrile containing 0.1% (v/v) trifluoroacetic acid (TFA) and spotted  ...  Pretreatment at 24 uC in 2% (v/v) HNO 3 for 1 h led to the quantitative release of Fe (data not shown).  ... 
doi:10.1038/nature09265 pmid:20639861 fatcat:gccvjc7q3rbsze422zuw4lfdnq

Detection of Carbohydrates and Steroids by Cation-Enhanced Nanostructure-Initiator Mass Spectrometry (NIMS) for Biofluid Analysis and Tissue Imaging

Gary J. Patti, Hin-Koon Woo, Oscar Yanes, Leah Shriver, Diane Thomas, Wilasinee Uritboonthai, Junefredo V. Apon, Rick Steenwyk, Marianne Manchester, Gary Siuzdak
2010 Analytical Chemistry  
Nanostructure-initiator mass spectrometry (NIMS) is a highly sensitive, matrix-free technique that is well suited for biofluid analysis and imaging of biological tissues. Here we provide a new technical variation of NIMS to analyze carbohydrates and steroids, molecules that are challenging to detect with traditional mass spectrometric approaches. Analysis of carbohydrates and steroids was accomplished by spray depositing NaCl or AgNO 3 on the NIMS porous silicon surface to provide a uniform
more » ... ronment rich with cationization agents prior to desporption of the fluorinated polymer initiator. Laser desorption/ionization of the ion-coated NIMS surface allowed for Na + cationization of carbohydrates and Ag + cationization of steroids. The reliability of the approach is quantitatively demonstrated with a calibration curve over the physiological range of glucose and cholesterol concentrations in human serum (1-200 µM). Additionally, we illustrate the sensitivity of the method by showing its ability to detect carbohydrates and steroids down to the 800-amol and 100-fmol levels, respectively. The technique developed is well suited for tissue imaging of biologically significant metabolites such as sucrose and cholesterol. To highlight its applicability, we used cation-enhanced NIMS to image the distribution of sucrose in a Gerbera jamesonii flower stem and the distribution of cholesterol in a mouse brain. The flower stem and brain sections were placed directly on the ion-coated NIMS surface without further preparation and analyzed directly. The overall results reported underscore the potential of NIMS to analyze and image chemically diverse compounds that have been traditionally challenging to observe with mass spectrometry-based techniques. Mass spectrometry imaging (MSI) is emerging as a powerful technique to probe the distribution of molecules within biological systems. 1-3 The molecular specificity of MSI offers significant advantages over traditional imaging techniques such as fluorescence microscopy, electron microscopy, and radiography. MSI has proven important to understanding tumor pathology, 4 biomarkers, 5,6 drug distribution, 7-9 and changes in the chemical organization of tissues under a variety of therapeutic conditions. 10-12 The applicability of MSI depends largely upon several parameters including sample preparation, method of ionization, sensitivity, resolution, and speed of the analysis. Various MSI strategies have been employed including matrix-assisted laser desorption/ionization (MALDI), 1,13,14 atmospheric pressure-MALDI (AP-MALDI), 15,16 time-of-flight secondary ion mass spectrometry (TOF-SIMS), 2,17,18 desorption electrospray ionization (DESI), 8, 19 and laser ablation
doi:10.1021/ac9014353 pmid:19961200 pmcid:PMC2802282 fatcat:odet66j2l5edbf7qsnbjwarcxm

A Mass Spectrometry Plate Reader: Monitoring Enzyme Activity and Inhibition with a Desorption/Ionization on Silicon (DIOS) Platform

Zhouxin Shen, Eden P. Go, Alejandra Gamez, Junefredo V. Apon, Valery Fokin, Mike Greig, Manuel Ventura, John E. Crowell, Ola Blixt, James C. Paulson, Raymond C. Stevens, M. G. Finn (+1 others)
2004 ChemBioChem  
doi:10.1002/cbic.200400008 pmid:15239048 fatcat:f75yvysonbbndlxhzlmmj7lelq

A Computational Framework for Proteome-Wide Pursuit and Prediction of Metalloproteins using ICP-MS and MS/MS Data

W Andrew Lancaster, Jeremy L Praissman, Farris L Poole, Aleksandar Cvetkovic, Angeli Menon, Joseph W Scott, Francis E Jenney, Michael P Thorgersen, Ewa Kalisiak, Junefredo V Apon, Sunia A Trauger, Gary Siuzdak (+2 others)
2011 BMC Bioinformatics  
The number of proteins deemed significant ranged from 45 for V to 153 for Ni ( Table 1 ).  ...  The proteins falling in the significant regions for each metal were then hierarchically clustered by co-occurrence in fractions, with the number of clusters ranging from 5 for V to 16 for Co ( Table 1  ... 
doi:10.1186/1471-2105-12-64 pmid:21356119 pmcid:PMC3058030 fatcat:bq5tmfealvd6lczh6n26ukvbxu

Clathrate nanostructures for mass spectrometry

Trent R. Northen, Oscar Yanes, Michael T. Northen, Dena Marrinucci, Winnie Uritboonthai, Junefredo Apon, Stephen L. Golledge, Anders Nordström, Gary Siuzdak
2007 Nature  
Low-resistivity (0.01-0.02 V cm) P-type AE100ae (boron) silicon was etched at 48 mA cm 22 for 30 min.  ...  Bacteriorhodopsin was a gift from V.-P. Jaakola and R. C. Stevens. Fresh blood and urine from humans were used in this study.  ...  Single-side-polished silicon wafers, P/boron-type, AE100ae orientation, low resistivity (0.01-0.02 V cm), 525 6 25 mm thick and 100 mm in diameter, were obtained from Silicon Valley Microelectronics.  ... 
doi:10.1038/nature06195 pmid:17960240 fatcat:nmykhwt245atjkt7fprcyyikau

Metabolomics relative quantitation with mass spectrometry using chemical derivatization and isotope labeling

Grace O'Maille, Eden P. Go, Linh Hoang, Elizabeth J. Want, Colin Smith, Paul O'Maille, Anders NordstrÖm, Hirotoshi Morita, Chuan Qin, Wilasinee Uritboonthai, Junefredo Apon, Richard Moore (+2 others)
2008 Spectroscopy (Ottawa)  
Mobile phase A consisted of water/acetonitrile/formic acid (95/5/0.1 (v/v/v)), and B consisted of acetonitrile/formic acid (100/0.1 (v/v)).  ...  The dried serum/plasma metabolite extract was reconstituted in 50 µl H 2 O/acetonitrile (95/5, v/v) prior to LC-ESI-MS analysis.  ... 
doi:10.1155/2008/715905 fatcat:27izthyhorbdrhfn3vwt5cn5pi

Monday posters

2005 Journal of the American Society for Mass Spectrometry  
Vershchagin; Maja V.  ...  Page; Keqi Tang; Aleksey V. Tolmachev; Anil K. Shukla; Richard D.  ... 
doi:10.1016/j.jasms.2005.03.044 fatcat:ykfa5uu5irfr3egnxxloup3y54

Tuesday posters

2005 Journal of the American Society for Mass Spectrometry  
Ginter; Murray V.  ...  Lloyd; Murray V.  ... 
doi:10.1016/j.jasms.2005.03.045 fatcat:jowj7ogfnjgufjh2gaci4gjabm

Wednesday posters

2004 Journal of the American Society for Mass Spectrometry  
Go 1 ; Junefredo V.  ...  Snellinger; Murray V.  ... 
doi:10.1016/j.jasms.2004.04.020 fatcat:w7igs6jxobckbawzf4praqma5y