5phosphorylated

5-phosphorylated refers to molecules that contain a phosphate group esterified to the fifth position of a sugar or ring structure, most commonly the 5' carbon of a ribose in nucleotides. In biological contexts, the term is often used to describe 5'-phosphate forms, such as nucleoside monophosphates (NMPs) like AMP, CMP, GMP, and UMP, which have a single phosphate attached at the 5' position. The 5' end of RNA and DNA strands also bears a phosphate group in many forms, and during transcription RNA molecules can begin with a 5' triphosphate before processing or capping. A notable specialized 5' structure in eukaryotic mRNA is the 5'-cap, a methylated guanine linked via a 5'-5' triphosphate bridge, which plays a key role in mRNA stability and translation.

Chemical and biological significance arises from the phosphate group’s negative charge and hydrophilicity, which influence the molecule’s solubility, conformation, and interactions with enzymes and other biomolecules. 5'-phosphate groups are essential substrates for enzymes such as kinases and polymerases, and they participate in pathways of energy transfer (as in ATP and other nucleoside triphosphates) and nucleic acid metabolism, including synthesis, repair, and ligation of nucleic acids. The presence or absence of a 5'-phosphate can affect the efficiency of ligation reactions in molecular cloning and the processing of RNA transcripts.

Synthesis and detection of 5-phosphorylated compounds typically involve chemical phosphorylation or enzymatic transfer of phosphate groups, with analytical methods like chromatography and mass spectrometry used to confirm phosphorylation status. See also phosphate group, phosphorylation, nucleotides, and nucleic acid ligation.