Journal of the American Society for Mass Spectrometry最新文献

{"title":"Note: An Integrated Miniature Time-of-Flight Mass Spectrometer System with 3D Printing Assisted Design of Versatile Pocket-Size Laser-Induced Acoustic Desorption Source","authors":"Qiaolin Wang,&nbsp;, ,&nbsp;Yulong Shi,&nbsp;, ,&nbsp;Xiaojian Li,&nbsp;, ,&nbsp;Junyao Zhang,&nbsp;, ,&nbsp;Zefeng Hua,&nbsp;, ,&nbsp;Xinyan Yang,&nbsp;, ,&nbsp;Zhongfa Sun,&nbsp;, ,&nbsp;Zhengbo Qin*,&nbsp;, and ,&nbsp;Xianfeng Zheng*,&nbsp;","doi":"10.1021/jasms.5c00241","DOIUrl":"10.1021/jasms.5c00241","url":null,"abstract":"<p >An integrated miniature time-of-flight mass spectrometer (TOF-MS) system coupled with a pocket-size 3D-printed laser-induced acoustic desorption (LIAD) source is described. This 3D-printed LIAD source utilizes only a miniature deceleration motor to achieve two-dimensional motion of the target surface, simplifying the source structure and improving the long-term stability of mass spectrometry measurements. It has been successfully applied to analyze the model molecule creatinine and ingredients in an energy beverage (Red Bull), where main natural nutrients were clearly identified. By adjusting the 3D printing parameters, the source can be readily adapted to various application scenarios requiring different sizes. This work provides a simple and efficient 3D-printed source injection strategy for subsequent investigations in molecular reaction dynamics.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2319–2323"},"PeriodicalIF":2.7,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145022525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Algorithm-Driven Chromatographic Method for Prostaglandin Isomer Identification via Tandem Mass Spectrometry","authors":"Toshinobu Hondo*,&nbsp;, ,&nbsp;Yumi Miyake,&nbsp;, and ,&nbsp;Michisato Toyoda,&nbsp;","doi":"10.1021/jasms.5c00231","DOIUrl":"10.1021/jasms.5c00231","url":null,"abstract":"<p >This study explores the computational isolation of prostaglandin (PG) isomers, specifically PG E₂ (PGE₂) and D₂ (PGD₂), to enhance method development efficiency and provide insights into their retention behavior during supercritical fluid extraction (SFE) combined with supercritical fluid chromatography (SFC)-tandem mass spectrometry (MS/MS). Although PGE₂ and PGD₂ are positional isomers that yield identical product ions in MS/MS, they serve distinct biological roles. This research illustrates the efficacy of selected reaction monitoring (SRM)-based techniques for differentiating coeluting isomers. Despite the challenges posed by baseline resolution, simplified computational methods successfully distinguished between PGE₂ and PGD₂, demonstrating the potential for high-throughput PG analysis without the necessity for complete chromatographic peak resolution. By employing least-squares estimation to solve a linear system, the abundance ratio of PGE₂ to PGD₂ was derived from intensity ratios across four SRM transitions, achieving precise quantification even with poorly resolved SFC peaks. The study highlights critical factors affecting PG retention, such as the choice of the stationary phase, temperature regulation, and reduction of stainless steel interactions, which can diminish signal intensity. A significant observation is the concentration-dependent suppression effect of the entrainer when interacting with the hepatocyte matrix, underscoring the importance of effective matrix management in SFE/SFC-MS/MS. These findings advance the development of a robust, high-throughput analytical platform for PG quantification and lipidomics research applications.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2267–2275"},"PeriodicalIF":2.7,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145013625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Protein Ion Relative Ratio Quantification in Top-down Electrospray Ionization-Mass Spectrometry Using Site-Specific Acetylated Recombinant Histone H3 Proteoforms","authors":"Kin-Wing Lui,&nbsp;, ,&nbsp;Sai-Ming Ngai,&nbsp;, and ,&nbsp;Ting-Fung Chan*,&nbsp;","doi":"10.1021/jasms.5c00079","DOIUrl":"10.1021/jasms.5c00079","url":null,"abstract":"<p >Electrospray ionization (ESI)-mass spectrometry (MS) is a key platform for analyzing post-translationally modified proteins. With continuous advances in MS instruments and data analysis methods, top-down analysis of intact proteoforms has become highly feasible. To accurately quantify proteoforms with varying post-translational modifications (PTMs), the influence of PTMs on the ESI-MS detection efficiency must be considered. Two decades ago, Kelleher and co-workers proposed using protein ion relative ratios (PIRRs) and fragment ion relative ratios (FIRRs) in ESI-MS for proteoform quantification. While FIRR quantification has been extensively studied, the reliability of PIRR quantification─particularly for proteoforms with varying PTM degrees─remains under-evaluated. In this study, we further validated the fidelity of PIRR quantification in top-down ESI-MS using various site-specifically acetylated recombinant histone H3 proteoforms. These proteoforms, carrying varied degrees of acetylation, were produced using an orthogonal translation system that incorporates acetyllysine at the amber stop codons. After absolute quantification by UV spectrophotometry, samples were mixed in isometric ratios and analyzed by either direct infusion-ESI-MS or weak cation exchange/hydrophilic interaction-ESI-MS. Our results show that PIRRs match theoretical ratios regardless of the acetylation degree or site. These findings reinforce the validity of top-down proteoform quantification, especially for histone proteins.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2048–2058"},"PeriodicalIF":2.7,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/jasms.5c00079","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Germ-Specific Triacylglycerols as Potential Biomarkers for Authenticating Zhongzi Purple Rice, a Cultivar Recognized for Its Nutritional Value","authors":"Zhenchao Shao,&nbsp;, ,&nbsp;Shuangshuang Di,&nbsp;, ,&nbsp;Jie Lian*,&nbsp;, and ,&nbsp;Honggang Nie*,&nbsp;","doi":"10.1021/jasms.5c00114","DOIUrl":"10.1021/jasms.5c00114","url":null,"abstract":"<p >Zhongzi purple rice is recognized as a nutritionally superior whole-grain variety, containing higher levels of protein, iron, dietary fiber, and vitamin B6 compared to conventional rice. While the nutritional profile of Zhongzi purple rice is well-established, the spatial distribution and structural specificity of its lipid components, especially germ-specific triacylglycerols (TAGs), remain poorly characterized. This study employs a multimodal mass spectrometric strategy to investigate the lipidomic uniqueness of the Zhongzi purple rice. The strategy combines matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) for spatial analysis, high-resolution mass spectrometry (HRMS) for primary analysis, and high-resolution tandem mass spectrometry with atmospheric pressure chemical ionization (APCI-HRMS/MS) for secondary analysis. MALDI-MSI identified seven metabolites in Zhongzi purple rice that exhibited germ-specific accumulation. In contrast, these metabolites showed markedly reduced signal intensities and lacked structured spatial distribution in conventional purple, black, and brown rice. Using a combination of lipidomic database interrogation, HRMS molecular formula validation, and APCI-HRMS/MS structural elucidation, we identified these metabolites as unsaturated fatty acid-enriched TAGs. Specifically, they were TAG(16:0/16:0/18:2), TAG(16:0/16:0/18:1), TAG(16:0/18:1/18:3), TAG(16:0/18:1/18:2), TAG(16:0/18:1/18:1), TAG(18:1/18:2/18:2), and TAG(18:1/18:1/18:2). The high unsaturation of these TAGs contributes to improved lipid hydrolysis efficiency, metabolic health benefits, and oxidative stability. These properties highlight Zhongzi purple rice as a potential functional food source. Due to their germ-specific accumulation, these compounds can act as potential biomarkers for authenticating Zhongzi purple rice and detecting adulterants. This provides a practical solution to commercial challenges in the industry. This study pushes the boundaries of cereal lipidomics through the integration of spatially resolved imaging and structural validation. The results shed light on the role of lipids in driving the nutritional and metabolic benefits of whole grains.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2094–2102"},"PeriodicalIF":2.7,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144999345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Power of Many: An Ensemble Approach to Spectral Similarity","authors":"Javier E. Flores,&nbsp;, ,&nbsp;David J. Degnan,&nbsp;, ,&nbsp;Yuri E. Corilo,&nbsp;, ,&nbsp;Chaevien S. Clendinen,&nbsp;, and ,&nbsp;Lisa M. Bramer*,&nbsp;","doi":"10.1021/jasms.5c00176","DOIUrl":"10.1021/jasms.5c00176","url":null,"abstract":"<p >Quantifying the similarity between two mass spectra─a known reference mass spectrum and an unidentified sample mass spectrum─is at the heart of compound identification workflows in gas chromatography–mass spectrometry (GC-MS). The reference spectrum most like the sample is assigned as its identification (provided some quantitative similarity threshold is met, e.g., 80%) and thus accurately measuring similarity is essential. Significant research has gone toward developing metrics for this purpose, each of which has attempted to improve upon existing methods by incorporating GC-MS-specific information (e.g., peak ratios or retention times) or adopting various statistical and algorithmic frameworks. While this active development has led to a plethora of similarity metrics with demonstrated value across different contexts, the unfortunate consequence has been confusion surrounding which metric should be used as a global standard. No such metric is currently accepted as the standard method because different metrics have demonstrated optimal performance in different contexts. In this work, we propose an ensemble approach to spectral similarity scoring that combines the collective information from across existing similarity metrics to form an improved, globally representative similarity metric as a step toward establishing a global standard method. The resulting ensemble metrics are evaluated on over 88,000 spectra of varying complexity and demonstrate improved abilities to accurately rank the correct reference spectrum as the top-matching candidate for a sample relative to the rankings generated by individual similarity scores.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2164–2170"},"PeriodicalIF":2.7,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144999469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Specificity and Sensitivity Imaging of Neutral Lipids Using Salt-Enhanced MALDI TIMS","authors":"Kameron R. Molloy,&nbsp;, ,&nbsp;Martin Dufresne,&nbsp;, ,&nbsp;Madeline E. Colley,&nbsp;, ,&nbsp;Lukasz G. Migas,&nbsp;, ,&nbsp;Raf Van de Plas,&nbsp;, and ,&nbsp;Jeffrey M. Spraggins*,&nbsp;","doi":"10.1021/jasms.5c00202","DOIUrl":"10.1021/jasms.5c00202","url":null,"abstract":"<p >Neutral lipids are vital to various cellular processes and disease pathologies. However, their characterization by matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) remains challenging due to poor ionization efficiency and difficulties distinguishing subtle structural differences among numerous isomeric and isobaric species. In this study, we enhanced neutral lipid detection by incorporating isotonic metal–cation washes into our MALDI IMS sample preparation workflow. Resulting salt adducts improved neutral lipid isobar and isomer separation by using trapped ion mobility spectrometry (TIMS). This approach increased both sensitivity and specificity for neutral lipid IMS experiments across multiple organ types, including murine brain, rabbit adrenal gland, human colon, and human kidney. Comparative analyses revealed that the most effective salt wash was tissue-dependent. However, the Na⁺ carbonate buffer solution (CBS) wash showed the greatest overall increase in neutral lipid detection. These findings provide a robust framework for mapping neutral lipids across multiple tissues and disease states and allow for the detailed characterization of neutral lipid isomers and isobars in complex biological tissues.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2213–2221"},"PeriodicalIF":2.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/jasms.5c00202","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144999299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the QCxMS2 Method for the Calculation of Collision-Induced Dissociation Spectra via Automated Reaction Network Exploration","authors":"Johannes Gorges,&nbsp;, ,&nbsp;Marianne Engeser*,&nbsp;, and ,&nbsp;Stefan Grimme*,&nbsp;","doi":"10.1021/jasms.5c00234","DOIUrl":"10.1021/jasms.5c00234","url":null,"abstract":"<p >Collision-induced dissociation mass spectrometry (CID-MS) is an important tool in analytical chemistry for the structural elucidation of unknown compounds. The theoretical prediction of the CID spectra plays a critical role in supporting and accelerating this process. To this end, we adapt the recently developed QCxMS2 program originally designed for the calculation of electron ionization (EI) spectra to enable the computation of CID-MS. To account for the fragmentation conditions characteristic of CID within the automated reaction network discovery approach of QCxMS2 we adapted the internal energy distribution to match the experimental conditions. This distribution can be adjusted via a single parameter to approximate various activation settings, thereby eliminating the need for explicit simulations of the collisional process. We evaluate our approach on a test set of 13 organic molecules with diverse functional groups, compiled specifically for this study. All reference spectra were recorded consistently under the same measurement conditions, including both CID and higher-energy collisional dissociation (HCD) modes. Overall, QCxMS2 achieves a good average entropy similarity score (ESS) of 0.687 for the HCD spectra and 0.773 for the CID spectra. The direct comparison to experimental data demonstrates that the QCxMS2 approach, even without explicit modeling of collisions, is generally capable of computing both CID and HCD spectra with reasonable accuracy and robustness. This highlights its potential as a valuable tool for integration into structure elucidation workflows in analytical mass spectrometry.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2276–2289"},"PeriodicalIF":2.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144991149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experiment and Simulation Study of Automatic Temperature Control FAIMS Chip","authors":"Xiaoxia Du,&nbsp;, ,&nbsp;Haonan Liang,&nbsp;, ,&nbsp;Yao Li,&nbsp;, ,&nbsp;Xingxing A Luo,&nbsp;, ,&nbsp;Yuqiao Zhang,&nbsp;, and ,&nbsp;Hua Li*,&nbsp;","doi":"10.1021/jasms.4c00427","DOIUrl":"10.1021/jasms.4c00427","url":null,"abstract":"<p >The temperature of the carrier gas will affect the performance of high-field asymmetric ion waveform mobility spectrometry (FAIMS), changing the height and position of the peaks of the FAIMS spectrum. In this study, we explored the influence of temperature on the FAIMS spectrum through experiment and simulation. In the experiment, the PCB self-heating temperature control FAIMS system was used to study the effects of temperature changes on the FAIMS spectra of ethanol, acetic acid, acetone, and ethyl acetate, and the coefficient solving methods of mobility <i>a</i>₂ and <i>a</i>₄ were derived in detail. Based on the experimental data, the mobility coefficients <i>a</i>₂ and <i>a</i>₄ were solved and replaced by the simulation software SIMION. The results show that as the temperature increases, the peak height of the spectrum of FAIMS decreases, and there will be a certain amount of offset in the position of the peaks in the spectrum. Through simulation, it is found that during the heating process, the number of ions decreases from approximately 60 to 6, and the compensation voltages of acetone, ethanol, acetic acid, and ethyl acetate change by about 1.1, 0.7, 0.3, and 0.1 V, respectively. This study provides a detailed solution process for the calculation of the ion mobility coefficients in the SIMION simulation, and the use of temperature control can effectively improve the resolution and accuracy of FAIMS in volatile organic compounds (VOCs) detection.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2026–2035"},"PeriodicalIF":2.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144999296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Online Buffer Exchange Platform for Charge Detection Mass Spectrometry Analysis of AAVs and AAV-Antibody Complexes","authors":"Chen Du,&nbsp;, ,&nbsp;Victoria C. Cotham*,&nbsp;, ,&nbsp;Garima Thakur,&nbsp;, ,&nbsp;Sheldon Mink,&nbsp;, ,&nbsp;Andrew D. Tustian,&nbsp;, ,&nbsp;Sven Møller-Tank,&nbsp;, ,&nbsp;Shunhai Wang*,&nbsp;, and ,&nbsp;Ning Li,&nbsp;","doi":"10.1021/jasms.5c00206","DOIUrl":"10.1021/jasms.5c00206","url":null,"abstract":"<p >Adeno-associated viruses (AAVs) are leading vectors in gene therapy that have demonstrated great potential in combating a wide range of human diseases. To enhance specificity and reduce dosing requirements, antibody-retargeted AAVs have emerged as a promising strategy to redirect vectors to novel receptors, thereby achieving improved efficacy and safety. However, effective characterization of AAVs and AAV-antibody complexes is complicated by heterogeneities that arise from variations in capsid protein assembly, genome integrity, and antibody decorations, demanding high-resolution techniques beyond traditional methods. Charge detection mass spectrometry (CDMS) is an emerging technique that effectively characterizes complex AAV samples by directly measuring ion charge. This technique is typically performed using static infusion-based nanoelectrospray ionization with long acquisition times, which is highly manual and subject to unstable spray and sample instability. To address limitations of static infusion in CDMS, we have developed a novel automated platform: size-exclusion chromatography-based flow injection coupled with CDMS (SEC-FI-CDMS). This platform streamlines and automates sample introduction with a dual-flow setup, enabling fast online desalting in high-flow mode and stable, prolonged infusion in low-flow mode for Orbitrap-based CDMS analysis. It accurately determines AAV genome packaging ratios and masses, differentiates capsid assembly and payload variations, and resolves antibody decoration on AAV-antibody complexes. This comprehensive characterization supports AAV manufacturing and development, paving the way for more effective next generation gene therapies.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2230–2238"},"PeriodicalIF":2.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/jasms.5c00206","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144938273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Micrococcus luteus Lipidome Containing Novel Lipid Families by Multiple Stage Linear Ion-Trap with High Resolution Mass Spectrometry","authors":"Brian A. Kleiboeker,&nbsp; and ,&nbsp;Fong-Fu Hsu*,&nbsp;","doi":"10.1021/jasms.5c00133","DOIUrl":"10.1021/jasms.5c00133","url":null,"abstract":"<p ><i>Micrococcus luteus</i> (<i>M. luteus</i>) is a ubiquitous, long-existing Gram-positive bacterium with a distinctive yellow or golden color. It is a model organism for laboratory studies due to its small genome and ease of cultivation. However, only limited knowledge about its constituent lipid structure is known, and its entire lipid profile remains unclear. Here, we applied linear ion trap (LIT) multiple-stage mass spectrometry (MS<i>ⁿ</i>) with high resolution for structural characterization of the native lipid extract, along with GC/MS analysis of the acid hydrolysate to reveal the structural details of the entire lipidome, which includes the major phosphatidylglycerol (PG), cardiolipin (CL), phosphatidylinositol (PI), dimannosyl diacylglycerol (DMDG), and minor diacylglycerol (DAG) lipid families. Importantly, we also found two extra lipid families, the new phosphatidyl 1,3-propanediol and the known polyprenyl 1-phosphosate that was not previously reported for <i>M. luteus</i>. We also revealed the unique lipidome simplified by the dominance of branched 15:0-fatty acid substituents (&gt;90% branched 15:0-FA with anteiso-15:0 to iso-15:0 abundance ratio of 4/1), which is in line with the small genome of <i>M. luteus</i>. In addition, the applied LIT MS^<i>n</i> mass spectrometry revealed a fragmentation pathway that undergoes internal loss of a glycerol residue specific to DMDG, leading to its structural characterization.</p>","PeriodicalId":672,"journal":{"name":"Journal of the American Society for Mass Spectrometry","volume":"36 10","pages":"2117–2125"},"PeriodicalIF":2.7,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144938329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}