@Article{phyton.2024.050450,
AUTHOR = {Bairu Li, Jingyu Jia, Hemin Wang, Jiaju Sun, Enyan Chen, Xin Li},
TITLE = {4-Hydroxy-2-Oxoglutaric Acid, A Key Metabolite Involved in Trypsin-Regulation of Arginine Metabolism in <i>Hylocereus undatus</i> during Storage},
JOURNAL = {Phyton-International Journal of Experimental Botany},
VOLUME = {93},
YEAR = {2024},
NUMBER = {5},
PAGES = {885--900},
URL = {http://www.techscience.com/phyton/v93n5/56748},
ISSN = {1851-5657},
ABSTRACT = {Trypsin, a novel superoxide scavenger, significantly enhances the storage quality of <i>Hylocereus undatus</i> (<i>H. undatus</i>). To elucidate the preservation mechanism of trypsin on <i>H. undatus</i>, a widely targeted metabolomic analysis, and transcriptomics analysis were conducted. Firstly, a total of 453 metabolites were identified, with organic acids and their derivatives constituting the largest proportion (25%). Amino acids and their metabolites, prominent among organic acids, were further analyzed. Among them, 73 metabolites were associated with amino acids, and 37 exhibited significant differences. The most enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway was arginine biosynthesis (map00220), with polyamine metabolites showing the most pronounced differences, particularly spermine (FC = 1.7594). Compared with the control group, 4-hydroxy-2-oxoglutaric acid was significantly upregulated (FC = 2.117) in the process of spermine biosynthesis. Furthermore, the results of Gene Ontology (GO) and KEGG enrichment analysis of the <i>H. undatus</i> transcriptome profile revealed that trypsin treatment led to 187 differentially expressed genes associated with arginine. Both GO and KEGG analyses exhibited significant enrichment in the spermine biosynthetic process (GO:0006597) (map:00220) within the arginine biosynthesis pathway. Moreover, most enzymes and metabolites within the spermine biosynthesis pathway in <i>H. undatus</i> were upregulated. The results of the PPI network highlighted that ADC, SPDS, and SAMDC, among others, were pivotal proteins involved in trypsin-regulated arginine metabolism and spermine synthesis. This study revealed that trypsin could significantly delay postharvest senescence of <i>H. undatus</i> at room temperature. This effect might be attributed to trypsin triggering the synthesis of 4-hydroxy-2-oxoglutaric acid in the fruit peel, thereby promoting the biosynthesis of spermine and other polyamines.},
DOI = {10.32604/phyton.2024.050450}
}