malonüüli

Malonüüli is a term used primarily in biochemistry to denote the malonyl moiety, a two‑carbon acyl group derived from malonic acid. The chemical formula for malonyl is C3H4O3. It is most commonly encountered in the form of malonyl‑Coenzyme A, a key intermediate in fatty acid biosynthesis and polyketide synthesis. Malonyl‑CoA is generated by the carboxylation of acetyl‑CoA with the enzyme acetyl‑CoA carboxylase, a reaction that consumes ATP and bicarbonate.

In fatty acid synthesis, malonyl‑CoA provides two-carbon units that are sequentially condensed by the fatty acid synthase complex. Each condensation cycle shortens the growing acyl chain by one acetyl unit, creating the elongated fatty acid. In polyketide biosynthesis, malonyl donors enable the assembly of complex natural products such as antibiotics and pigments.

Malonyl groups can also be incorporated into proteins through post‑translational modification, a process known as malonylation. This modification occurs on lysine residues and can influence protein function, stability, and cellular localization. Research on protein malonylation has expanded understanding of metabolic regulation and epigenetic control.

Overall, malonüüli is a fundamental chemical entity in metabolic pathways, playing central roles in energy storage, biosynthetic processes, and regulatory mechanisms within living organisms.

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