Two genes (CM-AAT1 and CM-AAT2) with strong sequence homology (87% identity at the protein level) putatively involved in the formation of aroma volatile esters have been isolated from Charentais melon fruit. They belong to a large and highly divergent family of multifunctional plant acyl-transferases and show at most 21% identity to the only other fruit acyl-transferase characterized so far in strawberry. RT-PCR studies indicated that both genes were specifically expressed in fruit at increasing rates in the early and mid phases of ripening. Expression was severely reduced in ethylene-suppressed antisense ACC oxidase (AS) fruit and in wild-type (WT) fruit treated with the ethylene antagonist 1-MCP. Cloning of the two genes in yeast revealed that the CM-AAT1 protein exhibited alcohol acyl-transferase activity while no such activity could be detected for CM-AAT2 despite the strong homology between the two sequences. CM-AAT1 was capable of producing esters from a wide range of combinations of alcohols and acyl-CoAs. The higher the carbon chain of aliphatic alcohols, the higher the activity. Branched alcohols were esterified at differential rates depending on the position of the methyl group and the nature of the acyl donor. Phenyl and benzoyl alcohols were also good substrates, but activity varied with the position and size of the aromatic residue. The cis/trans configuration influenced activity either positively (2-hexenol) or negatively (3-hexenol). Because ripening melons evolve the whole range of esters generated by the recombinant CM-AAT1 protein, we conclude that CM-AAT1 plays a major role in aroma volatiles formation in the melon.
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http://dx.doi.org/10.1046/j.1432-1033.2002.02892.x | DOI Listing |
Int J Mol Sci
December 2024
Division of Clinical Geriatrics, Centre for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, 141 57 Stockholm, Sweden.
Choline-acetyltransferase (ChAT) is the key cholinergic enzyme responsible for the biosynthesis of acetylcholine (ACh), a crucial signaling molecule with both canonical neurotransmitter function and auto- and paracrine signaling activity in non-neuronal cells, such as lymphocytes and astroglia. Cholinergic dysfunction is linked to both neurodegenerative and inflammatory diseases. In this study, we investigated a serendipitous observation, namely that the catalytic rate of human recombinant ChAT (rhChAT) protein greatly differed in buffered solution in the presence and absence of Triton X-100 (TX100).
View Article and Find Full Text PDFFront Genet
December 2024
School of Life Sciences and Medicine, Shandong University of Technology, Zibo, Shandong, China.
Acylation represents a pivotal biochemical process that is instrumental in the modification of secondary metabolites throughout the growth and developmental stages of plants. The BAHD acyltransferase family within the plant kingdom predominantly utilizes coenzyme A thioester as the acyl donor, while employing alcohol or amine compounds as the acceptor substrates to facilitate acylation reactions. Using bioinformatics approaches, the gene family members in the genome of () were identified and characterized including gene structure, conserved motifs, -acting elements, and potential gene functions.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Cardiovascular Medicine, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, 330006, Jiangxi, China.
Liver enzymes are associated with liver function, but their relationship with body mass index (BMI) remains unclear. This cross-sectional study aimed to identify correlations between serum liver enzyme levels and BMI in the general population. The data were derived from the Dryad Digital Repository.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2025
Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China. Electronic address:
Abiotic stresses, including drought, salinity, and temperature extremes, are serious constraints to plant growth and agricultural development. These stresses that plants face in nature are often multiple and complex. Biotin carboxyl carrier protein subunit 2 (BCCP2) is one of the two subunits of biotin carboxyl carrier protein, which is a functional subunit of acetyl coenzyme A carboxylase, primarily studied for its role in fatty acid synthesis.
View Article and Find Full Text PDFLiver Int
January 2025
Department of Gastroenterology, Hepatopancreatology and Digestive Oncology, Hôpital Universitaire de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium.
The discovery of PNPLA3 as a genetic risk factor for liver disease has transformed our understanding of the pathogenesis of alcohol-related liver disease (ALD). The recent reclassification of fatty liver disease as steatotic liver disease (SLD), introducing metabolic dysfunction and alcohol-related liver disease (MetALD), has highlighted how genetic and environmental factors synergistically drive liver damage. The PNPLA3 rs738409 variant stands as a paradigmatic example of gene-environment interaction, where its effect on liver disease is dramatically amplified by alcohol consumption, obesity and type 2 diabetes.
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