EC Number |
Reaction |
Reference |
---|
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
activation of the enzyme may involve a transformation of S-adenosylmethionine into a form that promotes the generation of an adenosyl-5' free radical, which abstracts hydrogen from Lys to form 5'-deoxyadenosine as an intermediate |
-, 3391 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
evidence for participation of pyridoxal 5'-phosphate in a radical rearrangement, formation of an aldimine linkage between the pyridoxal 5'-phosphate and the beta-nitrogen of (3S)-3,6-diaminohexanoic acid |
-, 3392 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
formation of substrate radicals as intermediates |
3385 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
LAM catalytic cycle and reaction intermediate analysis for lysine 2,3-aminomutase |
746570 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
lysine 2,3-aminomutase (LAM) is a radical S-adenosyl-L-methionine (SAM) enzyme, catalysis is initiated by reductive cleavage of the S-adenosyl-L-methionine S-C5' bond, which creates the highly reactive 5'-deoxyadenosyl radical, the same radical generated by homolytic Co-C bond cleavage in B12 radical enzymes. The S-adenosyl-L-methionine surrogate S-3',4'-anhydroadenosyl-L-methionine can replace S-adenosyl-L-methionine as a cofactor in the isomerization of L-alpha-lysine to L-beta-lysine by 2,3-LAM, via the stable allylic anhydroadenosyl radical. The holoenzyme coordinates a pyridoxal 5'-phosphate cofactor through formation of an internal aldimine with Lys337. As L-alpha-lysine binds, pyridoxal 5'-phosphate forms an external aldimine linkage to the alpha-amine group of the substrate. Reductive cleavage of S-adenosyl-L-methionine leads to formation of 5'-dA radical. Electron transfer from the [4Fe4S]1+ cluster initiates radical S-adenosyl-L-methionine reactions by reductive cleavage of the S-C5' bond to create the highly reactive 5'-deoxyadenosyl radical |
-, 748031 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
lysine 2,3-aminomutase catalyzes S-adenosylmethionine and pyridoxal 5'-phosphate-dependent interconversion of L-lysine and L-beta-lysine, the reaction follows the pattern of adenosylcobalamin-dependent rearrangements, with hydrogen transfer from lysine through the adenosyl-C5' of S-adenosyl-L-methionine to beta-lysine. S-Adenosyl-L-methionine is cleaved to form 5'-deoxyadenosine-5'-yl followed by abstraction of C3(H) from pyridoxal-5'-phosphate-alpha-lysine aldimine to form PLP-R-lysine-3-yl. Pyridoxal 5'-phosphate-alpha-lysine-3-yl isomerizes to pyridoxal-beta-lysine-2-yl, and a hydrogen abstraction from 5'-deoxyadenosine regenerates 5'-deoxyadenosine-5'-yl and releases beta-lysine, 4 radicals in the reaction. Identification of radical intermediates. Reaction mechanism, detailed overview |
-, 746571 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
lysine radicals participate in the rearrangement mechanism |
3394 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
mechanism |
-, 3383, 3384, 3385 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
mechanism of radical rearrangement in the reaction |
3387 |
5.4.3.2 | L-lysine = (3S)-3,6-diaminohexanoate |
only the migrating (3-pro-R) hydrogen of alpha-Lys is involved in the intermolecular exchange |
3384 |