EC Number   |
Posttranslational Modification |
Reference |
|---|
   1.4.9.1 | more |
MauG catalyzes posttranslational modifications of methylamine dehydrogenase precursor to complete the biosynthesis of its protein-derived tryptophan tryptophylquinone cofactor |
725020 |
| 1.4.9.1 | more |
MauG protein is required for correct formation of prosthetic group tryptophan tryptophylquinone from Trp57 and Trp108 of enzyme beta subunit. Inactivation of MauG results in a biosynthetic intermediate of tryptophan tryptophylquinone with monohydroxylated Trp57 leading to an enzymatically inactve enzyme. In presence of intact MauG, cross-link of Trp57 with Trp108 occurs in vitro |
674171 |
| 1.4.9.1 | more |
ORF2 protein is necessary for posttranslational processing of enzyme gamma-subunit, probably participating in the formation of the intrapeptidyl thioether cross-links. In absence of ORF2, enzyme subunits alpha and beta are transferred normally to periplasm, while subunit gamma accumulates in the cytoplasm and stains negatively for redox-cycling quinone |
674556 |
| 1.4.9.1 | more |
structural features of the gamma subunit clearly indicate that it must undergo multiple posttranslational modifications before it can form an active QHNDH complex with the alpha and beta subunits. The qhpG gene encodes a putative FAD-dependent monooxygenase, which is required for the generation of the quinone cofactor in the gamma subunit |
741905 |
| 1.4.9.1 | more |
tryptophan tryptophyquinone, TTQ, the catalytic cofactor of enzyme MADH is not an exogenous cofactor but is instead derived from posttranslational modifications of the beta subunits of MADH via 8-electron oxidation of two specific tryptophans in the MADH beta-subunit, betaTrp57 and betaTrp108. The final 6-electron oxidation is catalyzed by the unusual c-type di-heme enzyme, MauG. reMADH has essentially the same structure as mature MADH, with preTTQ betaTrp108 coincident with its position in TTQ, and the plane of the betaTrp57-OH indole rotated about 20° from its position in TTQ |
742338 |
| 1.4.9.1 | proteolytic modification |
MauG is a diheme enzyme responsible for the posttranslational modification of two tryptophan residues in pre-MADH to form the tryptophan tryptophylquinone, TTQ, cofactor of methylamine dehydrogenase. MauG converts pre-MADH, containing monohydroxylated betaTrp57, to fully functional MADH by catalyzing the insertion of a second oxygen atom into the indole ring and covalently linking betaTrp57 to betaTrp108. MauG catalyzes a sixelectron oxidation to complete TTQ biosynthesis. Oxidizing equivalents may be provided by three mol of either O2, plus an electron donor, or H2O2. The overall reaction can be viewed as three two-electron oxidations to catalyze (i) insertion of an OH group at C6 of bTrp57, (ii) formation of the crosslink between bTrp57 and bTrp108, and (iii) oxidation of the quinol to the quinone, detailed overview |
713510 |
| 1.4.9.1 | proteolytic modification |
the diheme enzymeMauG catalyzes the post-translational modification of a precursor protein of methylamine dehydrogenase, preMADH, to complete the biosynthesis of its protein-derived tryptophan tryptophylquinone, TTQ, cofactor. This six-electron oxidation of preMADH requires long-range electron transfer as the structure of the MauG-preMADH complex reveals that the shortest distance between the modified residues of preMADH and the nearest heme of MauG is 14.0 A. Steady-state kinetic and single turnover kinetic studies of MauG-dependent oxidation of quinol MADH at pH 7.5, 25°C, overview |
711254 |
