Seed germination plays a pivotal role in plant growth and undergoes many intricate biochemical changes including lipid metabolism.Nevertheless,little is known about lipid changes and distributions in different structu...Seed germination plays a pivotal role in plant growth and undergoes many intricate biochemical changes including lipid metabolism.Nevertheless,little is known about lipid changes and distributions in different structures of soybean seeds during germination.Here,we applied mass spectrometry imaging(MSI)in conjunction with MS-based lipidomics to examine the lipid alterations in the embryo and cotyledon of soybean seeds during germination.To expand the coverage of lipid detection in soybean seeds,we used the novel techniques of matrix-assisted laser desorption/ionization(MALDI)and MALDI coupled with laser-postionization(MALDI-2).The results revealed that compared to MALDI,MALDI-2 enhanced the detected numbers and intensities of lipid species in various lipid classes,except for a few classes(e.g.,sphingomyelin and phosphatidylcholine).Lipidomic data showed that compared to the embryo,the cotyledon demonstrated slower but similar lipid changes during germination.These changes included the reduced levels of glycerolipids,phospholipids,and sterols,as well as the increased levels of lysophospholipids.Data from MALDI&MALDI-2 MSI supported and complemented these lipidomic findings.Our work highlights the significance of integrating lipid profiles and distributions to enhance our understanding of the metabolic pathways involved in seed germination.展开更多
目的对本院一位患者产后发热的血培养标本进行基质辅助激光解析电离飞行时间质谱(Matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF MS)分析和16S rRNA基因测序,以明确产后发热的原因,为临床...目的对本院一位患者产后发热的血培养标本进行基质辅助激光解析电离飞行时间质谱(Matrix-assisted laser desorption/ionization time of flight mass spectrometry,MALDI-TOF MS)分析和16S rRNA基因测序,以明确产后发热的原因,为临床诊治提供参考。方法对血培养瓶内阳性培养物转种于哥伦比亚血琼脂平板和巧克力琼脂平板,置于35℃、5%CO_(2)培养箱中孵育,同时直接涂片革兰染色镜检;对培养基上的目标菌株补充瑞氏染色,利用MALDI-TOF MS分析技术对目标菌株进行鉴定;根据质谱鉴定结果对目标菌株进行抗菌药物敏感性试验,采用16S rRNA基因测序技术对目标菌株进行验证确认。结果血培养瓶内阳性培养物直接涂片革兰染色镜检未见菌体结构。哥伦比亚血琼脂平板培养48 h可见针尖样透明小菌落,巧克力琼脂平板无细菌生长。哥伦比亚血琼脂上的目标菌株质谱鉴定结果为人型支原体,置信度为99.9%。抗菌药物敏感性试验结果显示该菌对米诺环素、多西环素、交沙霉素和克林霉素敏感,对其他药物耐药。目标菌株的16S rRNA基因序列结果与人型支原体标准菌株ATCC23114的核苷酸同源性为99.71%。结论患者产后发热的原因为人型支原体菌血症,MALDI-TOF MS分析技术对人型支原体的鉴定结果可靠,MALDI-TOF MS分析联合16S rRNA基因测序技术能提高少见病原体的诊断效率和准确性。展开更多
Cancer cell spheroids(CCS) are a valuable three-dimensional cell model in cancer studies because they could replicate numerous characteristics of solid tumors. Increasing researches have used matrix-assisted laser des...Cancer cell spheroids(CCS) are a valuable three-dimensional cell model in cancer studies because they could replicate numerous characteristics of solid tumors. Increasing researches have used matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) to investigate the spatial distribution of endogenous compounds(e.g., lipids) in CCS. However, only limited lipid species can be detected owing to a low ion yield by using MALDI. Besides, it is still challenging to fully characterize the structural diversity of lipids due to the existence of isomeric/isobaric species. Here, we carried out the initial application of MALDI coupled with laser-postionization(MALDI-2) and trapped ion mobility spectrometry(TIMS) imaging in HCT116 colon CCS to address these challenges. We demonstrated that MALDI-2 is capable of detecting more number and classes of lipids in HCT116 colon CCS with higher signal intensities than MALDI. TIMS could successfully separate numerous isobaric/isomeric species of lipids in CCS. Interestingly, we found that some isomeric/isobaric species have totally different spatial distributions in colon CCS. Further MS/MS imaging analysis was employed to determine the compositions of fatty acid chains for isomeric species by examining disparities in signal intensities and spatial distributions of product ions. This work stresses the robust ability of TIMS and MALDI-2 imaging in analyzing endogenous lipids in CCS, which could potentially become powerful tools for future cancer studies.展开更多
基金supported by National Natural Science Foundation of China(No.22036001)。
文摘Seed germination plays a pivotal role in plant growth and undergoes many intricate biochemical changes including lipid metabolism.Nevertheless,little is known about lipid changes and distributions in different structures of soybean seeds during germination.Here,we applied mass spectrometry imaging(MSI)in conjunction with MS-based lipidomics to examine the lipid alterations in the embryo and cotyledon of soybean seeds during germination.To expand the coverage of lipid detection in soybean seeds,we used the novel techniques of matrix-assisted laser desorption/ionization(MALDI)and MALDI coupled with laser-postionization(MALDI-2).The results revealed that compared to MALDI,MALDI-2 enhanced the detected numbers and intensities of lipid species in various lipid classes,except for a few classes(e.g.,sphingomyelin and phosphatidylcholine).Lipidomic data showed that compared to the embryo,the cotyledon demonstrated slower but similar lipid changes during germination.These changes included the reduced levels of glycerolipids,phospholipids,and sterols,as well as the increased levels of lysophospholipids.Data from MALDI&MALDI-2 MSI supported and complemented these lipidomic findings.Our work highlights the significance of integrating lipid profiles and distributions to enhance our understanding of the metabolic pathways involved in seed germination.
基金supported by the National Natural Science Foundation of China (Nos.22036001, 22276034 and 22106130)。
文摘Cancer cell spheroids(CCS) are a valuable three-dimensional cell model in cancer studies because they could replicate numerous characteristics of solid tumors. Increasing researches have used matrix-assisted laser desorption/ionization mass spectrometry imaging(MALDI-MSI) to investigate the spatial distribution of endogenous compounds(e.g., lipids) in CCS. However, only limited lipid species can be detected owing to a low ion yield by using MALDI. Besides, it is still challenging to fully characterize the structural diversity of lipids due to the existence of isomeric/isobaric species. Here, we carried out the initial application of MALDI coupled with laser-postionization(MALDI-2) and trapped ion mobility spectrometry(TIMS) imaging in HCT116 colon CCS to address these challenges. We demonstrated that MALDI-2 is capable of detecting more number and classes of lipids in HCT116 colon CCS with higher signal intensities than MALDI. TIMS could successfully separate numerous isobaric/isomeric species of lipids in CCS. Interestingly, we found that some isomeric/isobaric species have totally different spatial distributions in colon CCS. Further MS/MS imaging analysis was employed to determine the compositions of fatty acid chains for isomeric species by examining disparities in signal intensities and spatial distributions of product ions. This work stresses the robust ability of TIMS and MALDI-2 imaging in analyzing endogenous lipids in CCS, which could potentially become powerful tools for future cancer studies.
