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oai:www.ideals.illinois.edu:2142/108165 2023-07-11 col_2142_5131 col_2142_14789 com_2142_5130 com_2142_14788 com_2142_8903

Sweedler, Jonathan V Sweedler, Jonathan V Zhao, Huimin Kraft, Mary L Mitchell, Douglas A Ellis, Joanna Franklin 2020-08-26T23:58:40Z 2020-08-26T23:58:40Z 2022-08-26T23:58:55Z 2020-05-08 2020-05 Chemical heterogeneity is present in all biological systems—whether caused by lipid regulation and expression between individual mammalian single cells or by dynamic chemical communication in bacterial communities. Mass spectrometry imaging (MSI) is an untargeted and unlabeled analytical tool that enables us to look at molecular constituents in two or three dimensions. Exploring these additional spatial dimensions of heterogeneity is essential to understanding of specific molecular pathways or metabolic regulation at the single cell level. Here, we use a combination of secondary ion mass spectrometry (SIMS) imaging and matrix-assisted laser desorption/ionization (MALDI) MSI to detect, visualize, and piece together important chemical variations in biological systems. This thesis covers two main biological systems: a) bacterial communities and b) single mammalian cells with three main aims: 1) developing instrumentation and methodologies for visualizing chemical heterogeneity, 2) improving computational handling, visualization, and analysis of multidimensional mass spectrometry data, and 3) exploring these approaches to answer complex questions regarding chemical signaling and regulation and discovery of significant heterochemical variations between single cells. Development includes quantitative imaging techniques for SIMS imaging and an analytical workflow for characterization of microbially-influenced corrosion during co-culture interactions with correlated SIMS and MALDI MSI. Additionally, we have explored microbial communication during interactions with various antibiotics to map quorum sensing (QS) pathways in Pseudomonas aeruginosa and to observe how the initial arrangement and polymer surface interactions of P. aeruginosa biofilms alter their quinolone profile. Finally, we utilize microMS, an optically-guided mass spectrometry single cell profiling software, to obtain thousands of individual chemical profiles of single mammalian cells. We then developed laboratory-built bioinformatics tools to perform multivariate and clustering analyses and to uncover at least three cell types in rodent DRGs by their lipid, peptide, and protein content. This method was expanded upon and using metabolic information with high mass accuracy and high mass resolution obtained from tens-of-thousands of rat cerebellum cells to discover 101 unique clusters along with rare lipids present in only a small fraction of cells. Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2022-05-01 The student, Joanna Ellis, accepted the attached license on 2020-05-06 at 15:41. The student, Joanna Ellis, submitted this Dissertation for approval on 2020-05-06 at 16:17. This Dissertation was approved for publication on 2020-05-08 at 10:43. DSpace SAF Submission Ingestion Package generated from Vireo submission #15252 on 2020-08-25 at 17:29:53 Made available in DSpace on 2020-08-26T23:58:40Z (GMT). No. of bitstreams: 2 ELLIS-DISSERTATION-2020.pdf: 13821527 bytes, checksum: d2f911cbb9bb067d16f005f78214d8ab (MD5) LICENSE.txt: 4209 bytes, checksum: 5e5e11a55929cc735ade997608f78ffe (MD5) Previous issue date: 2020-05-08 Embargo set by: Seth Robbins for item 115778 Lift date: 2022-08-26T23:58:55Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only application/pdf http://hdl.handle.net/2142/108165 en Copyright 2020 Joanna F. Ellis secondary ion mass spectrometry SIMS matrix-assisted laser desorption/ionization MALDI mass spectrometry imaging MSI chemical signaling chemical heterogeneity quorum sensing Pseudomonas aeruginosa biofilm swarming single cell mass spectrometry Exploring chemical communication and chemical heterogeneity in biological systems with mass spectrometry imaging text Thesis Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.