Publications by authors named "Y Hacham"
Article Synopsis
- - Cysteine is crucial for making glutathione, which protects plants from stress, and methionine, important for cell growth and protein synthesis.
- - Under oxidative stress, glutathione competes with methionine for cysteine, with elevated oxidized glutathione (GSSG) levels suppressing methionine production by accelerating the breakdown of a key enzyme involved in its synthesis.
- - This study uncovers a feedback loop where glutathione promotes cysteine’s use for stress protection at the expense of methionine production, revealing a complex relationship affecting plant growth and nutritional quality under stress.
Alkaloids play an essential role in protecting plants against herbivores. Humans can also benefit from the pharmacological effects of these compounds. Plants produce an immense variety of structurally different alkaloids, including quinolizidine alkaloids, a group of bi-, tri-, and tetracyclic compounds produced by species.
View Article and Find Full Text PDFMethionine is an essential amino acid in mammals and a precursor for vital metabolites required for the survival of all organisms. Consequently, its inclusion is required in diverse applications, such as food, feed, and pharmaceuticals. Although amino acids and other metabolites are commonly produced through microbial fermentation, high-yield biosynthesis of L-methionine remains a significant challenge due to the strict cellular regulation of the biosynthesis pathway.
View Article and Find Full Text PDFArticle Synopsis
- - The study focuses on the enzyme methionine γ-lyase (MGL), crucial for methionine metabolism in plants, especially during seed development and germination, showing high accumulation levels in seeds compared to other plant organs.
- - Under heat and osmotic stress, seeds exhibit reduced methionine levels and increased isoleucine, with MGL activity ramping up to produce isoleucine as it serves as an osmoprotectant and energy source.
- - Transgenic seeds with MGL repression fail to accumulate methionine under standard conditions, and while germination efficiency is similar for various lines, those exposed to heat or salt stress show significantly reduced germination rates, highlighting MGL's role in
Arabidopsis (Arabidopsis thaliana) seeds expressing the feedback-insensitive form of cystathionine γ-synthase (AtD-CGS), the key gene of methionine (Met) synthesis, under the control of a seed-specific phaseolin promoter (SSE plants) show a significant increase in Met content. This elevation is accompanied by increased levels of other amino acids (AAs), sugars, total protein, and starch, which are important from a nutritional aspect. Here, we investigated the mechanism behind this phenomenon.
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