Moco

Most of the Moco enzymes catalyze oxygen atom addition or removal from their substrates. Molybdenum usually alternates between oxidation states VI and IV. The Mo(V) state forms as an intermediate as the active site is reconstituted by coupled proton—electron transfer processes (62). The working of the Moco enzymes depends on the 0x0 chemistry of Mo (VI), Mo(V), and Mo (TV). 

Fig. 5.10. The formula of one of the mononuclear molybdenum cofactors, Moco. Others have a nucleotide phosphate extension (see references to these elements in Further Reading). In sulfide-rich environments, tungsten replaced molybdenum. In some coenzymes, two pterins are bound to the metal ions.

Step by step introduction of more effective ways of handling cytoplasmic chemistry, using coenzymes and special metal cofactors, e.g. haem (Fe), vitamin B12(Co), F-430(Ni), chlorophyll(Mg) and Moco(Mo). 

In some studies the LC has been coupled to triple quadrupole and time-of-flight detectors. Moco and others (2006) used this technique to study phytochemicals including... 

Moco S, Bino RJ, Vorst O, Verhoeven HA, de Groot J, van Beek TA, Vervoort J and de Vos CH. 2006. A liquid chromatography-mass spectrometry-based metabolome database for tomato. Plant Physiol 141 (4) 1205—1218. 

Molybdenum co-factor (Moco), 77 33 Molybdenum complexes, 26 927-929, 949 Molybdenum(III) complexes, 17 26-27 Molybdenum compounds, 17 19-43 in advanced structural and heating materials, 17 38-39 in anticorrosion agents, 17 39 biological aspects of, 17 31-34 biological uses for, 17 39-40 biomedical uses for, 17 40 catalytic applications of, 17 38 chemistry of, 17 29-31... 

MORE COMPLEX COFACTORS MoCo, FeMoCo, P-CLUSTERS, H-CLUSTERS AND CuZ... 

Another factor that characterizes molybdenum and tungsten enzymes is that instead of using the metal itself, directly coordinated to amino acid side-chains of the protein, an unusual pterin cofactor, Moco, is involved in both molybdenum- and tungsten-containing enzymes. The cofactor (pyranopterin-dithiolate) coordinates the metal ion via a dithiolate side-chain (Figure 17.2). In eukaryotes, the pterin side-chain has a terminal phosphate group, whereas in prokaryotes, the cofactor (R in Figure 17.2) is often a dinucleotide. 

More Complex Cofactors MoCo, FeMoCo, P-Clusters, H-Clusters and CuZ.36... 

The molybdenum cofactor (Moco) is the essential component of a group of redox enzymes [20-22], which are diverse not only in terms of their phylogenetic distri-... 

Fig. 3.1. Moco biosynthesis in E. coli. (A) The present besides the dithiolene sulfurs shown carbon atom at position 8 of the guanosine here, with the metal being either penta- or...

The crystal structure of MPT synthase and the simultaneously determined NMR structure of the MoaD-related ThiS protein involved in thiamine biosynthesis [37] unambiguously demonstrated the evolutionary relationship between a subset of enzymes involved in the biosynthesis of S-containing cofactors (e.g. Moco, thiamine and certain EeS-clusters) and the process of ubiquitin activation. MoaD displays significant structural homology to human ubiquitin (Figure 3.3B and C), resulting in a superposition with a root mean square (rms) deviation of 3.6 A for 68 equivalent Ca atoms out of 76 residues in ubiquitin. The key secondary structure... 

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