Dataset Information

Chemical Proteomics Enhances the Understanding of 2AA Stress in Salmonella enterica

ABSTRACT: Pyridoxal 5’phosphate (PLP) is an essential cofactor for enzymes that catalyze diverse reactions in central metabolism. 2-aminoacrylate (2AA) is a reactive enamine and an obligate catalytic intermediate in some PLP-mediated reactions. In the absence of the enamine/imine deaminase RidA, Salmonella enterica accumulates 2AA, which causes cellular stress. 2AA can attack PLP in the active site of some enzymes and covalently inactivate the enzyme by forming a PLP/pyruvate adduct. Damage to a few target enzymes has been characterized in vivo and in vitro. The mechanism of 2AA attack suggests the majority of the cellular PLP-DEs would be targets of 2AA damage. Herein a chemical proteomics workflow that uses PL (pyridoxal) probes to enrich PLP-DEs with a click chemistry-based protocol was implemented to investigate the global scale of 2AA damage in S. enterica. Results showed PLP-DEs in S. enterica could be enriched when cells were labeled with two different PL probes. Labeling cells by providing the PL probe as the sole source of vitamin B6 found several proteins that were enriched when grown in conditions of high 2AA versus low 2AA stress. These data identified proteins previously shown to be attacked by 2AA and identified new candidate targets, showing this approach will contribute to continuing efforts to define the 2AA stress response with a global perspective. Growth analyses indicated 2AA stress impacts the salvage of PL probes, suggesting these and other PL probes will be valuable in future physiological studies to understand PLP salvage, a critical pathway in all organisms. In total, this study expands our understanding of 2AA metabolism and takes an initial step toward characterizing the global impact of 2AA stress in S. enterica.

INSTRUMENT(S):

ORGANISM(S): Salmonella Typhimurium (strain Lt2 / Sgsc1412 / Atcc 700720)

SUBMITTER: Nina Bach

LAB HEAD: Stephan Axel Sieber

PROVIDER: PXD060390 | Pride | 2025-05-24

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	DIANN_output.zip	Other
	Eclipse_raw_files.zip	Other
	Fusion_raw_files.zip	Other
	MaxQuant_output.zip	Other
	Salmonella_typhimurium_LT2_UP000001014.fasta	Fasta

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Project description:Vitamin B-6, folate and homocysteine may play a critical role in the colorectal cancer progression. This is a 4-y study and the specific aims are: 1) to compare vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation between subjects with colorectal polyps and colorectal cancer; 2) to study the effects of vitamin B-6, folate and homocysteine status on oxidative stress, antioxidant activities and DNA methylation in colorectal cancer patients; 3) to evaluate whether folic acid and/or pyridoxine supplementation had a beneficial effect on oxidative stress, antioxidant activities and DNA methylation in patients with colorectal; 4) to compare vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation between colorectal cancer patients and age-, sex-matched healthy subjects; 5) to evaluate the effect of vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation on the risk of colorectal cancer (odds ratio); 6) to follow the effects of vitamin B-6, folate and homocysteine status, oxidative stress, antioxidant activities and DNA methylation on the occurrence of colorectal cancer; 7) to follow the effects of pyridoxine and/or folic acid supplementation on the occurrence of colorectal cancer. This protocol is designed as a hospital-based cross-sectional, case-control, double blinded randomized placebo-controlled intervention and follow-up trial. Three hundred colorectal cancer patients and 300 age-, sex-matched controls who meet the inclusion criteria will be recruited from Taichung General Veterans Hospital. If cancer patients’ plasma pyridoxal 5’-phosphate (PLP) level less than 30 nmol/L will be asked to participate the intervention study and will be blinded and randomly assigned to either the 1) control (vitamin C, 100 mg/d); 2) 50 mg vitamin B-6; 3) 400 microgram/d folic acid; or 4) vitamin B-6 (50 mg/d) plus folic acid (400 microgram/d) for 1 year. Data on demography, anthropometry, medical history, food frequency questionnaire and 24-h diet recall will be collected. Cancer patients will have fasting blood drawn before surgery or receiving chemotherapy. Additionally, fasting blood samples will be obtained at month 0, 3, 6, 9 and 12 during intervention period and at month 6, 12, 18, 24, 30, 36, 42 and 48 during follow-up. Hematological, plasma and erythrocyte PLP, plasma pyridoxal and 4-pyridoxic acid, serum and erythrocyte folate, serum vitamin B-12, homocysteine, SAM, SAH, lipid peroxidation indicators (TBARS, oxidized LDL), glutathione, antioxidant enzymatic activities and DNA methylation and MTHFR 677C>T polymorphism will be measured.

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Chemical Proteomics Enhances the Understanding of 2AA Stress in Salmonella enterica

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