NodS: Difference between revisions
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NodS is an S-adenosyl-L-methionine (SAM)-dependent methyltransferase that methylates the deacetylated nitrogen atom at the nonreducing end of the chitooligosaccharide substrate, converting at the same time the S-adenosyl-L-methionine methyl donor into S-adenosyl-L-homocysteine, which is then released as a by-product (see figure above).<ref>PMID: 7494487</ref> | NodS is an S-adenosyl-L-methionine (SAM)-dependent methyltransferase that methylates the deacetylated nitrogen atom at the nonreducing end of the chitooligosaccharide substrate, converting at the same time the S-adenosyl-L-methionine methyl donor into S-adenosyl-L-homocysteine, which is then released as a by-product (see figure above).<ref>PMID: 7494487</ref> | ||
S-adenosyl-L-methionine-dependent methyltransferases, many of which have been reported to date, methylate a wide variety of substrates and are involved in diverse processes ranging from biosynthetic pathways to gene silencing. Those of them which have been structurally analyzed have been divided into five structural families known as classes I–V, class I, to which NodS belongs, being the most numerous.<ref>PMID: 12826405</ref> Its <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/2'>typical fold</scene> consists of a <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/3'>seven-stranded β-sheet</scene> ( | S-adenosyl-L-methionine-dependent methyltransferases, many of which have been reported to date, methylate a wide variety of substrates and are involved in diverse processes ranging from biosynthetic pathways to gene silencing. Those of them which have been structurally analyzed have been divided into five structural families known as classes I–V, class I, to which NodS belongs, being the most numerous.<ref>PMID: 12826405</ref> Its <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/2'>typical fold</scene> consists of a <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/3'>seven-stranded β-sheet</scene> (the strands are named 1-7 beginning from the N-terminus) with a <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/8'>reversed β-hairpin</scene> (residues 182-189) at the C-terminal end of the sheet, between strands β6 and β7. The sheet, which is characterized by a curvature due to the presence of three β-bulges, is surrounded on both sides by <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/5'>α-helices</scene> (named A-G beginning from the N-terminus), forming an <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/2'>α/β/α</scene> folding pattern. In the apo form shown here, only 6 out of 7 helices are visible. In addition to conventional helices, there are also three short, 3<sub>10</sub> helices (not represented as helices), each one-turn-long (residues 19-21, 63-65, 117-119), <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/7'>two of which are visible</scene> in the apo structure. The fact that <scene name='User:Marcin_Jozef_Suskiewicz/Sandbox_MarcinSuskiewicz/1/9'>strand β7 is inserted in an anti-parallel orientation</scene> results in a divergence from a classic Rossmann fold<ref>PMID: 4737475</ref>, to which the structure is otherwise classifiable. | ||