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Metal Control on Structure and Function of Ni(Fe) Dioxygenases Included in Methionine Salvage Pathway: Role of Tyr-Fragment and Macrostructures in Mechanism of Catalysis on Model Systems
Published in A. K. Haghi, Devrim Balköse, Omari V. Mukbaniani, Andrew G. Mercader, Applied Chemistry and Chemical Engineering, 2017
L. I. Matienko, L. A. Mosolova, V. I. Binyukov, E. M. Mil, G. E. Zaikov
The methionine salvage pathway (MSP) (Scheme 11.3) plays a critical role in regulating a number of important metabolites in prokaryotes and eukaryotes. ARDs Ni(Fe)-ARD are enzymes involved in the methionine recycle pathway, which regulates aspects of the cell cycle. The relatively subtle differences between the two metalloproteins complexes are amplified by the surrounding protein structure, giving two enzymes of different structures and activities from a single polypeptide Scheme 11.3).21 Both enzymes are members of the structural super family, known as cupins, which also include Fe–acetyl acetone dioxygenase (Dke1) and cysteine dioxygenase. These enzymes that form structure super family of cupins use a triad of histidine ligands (His), and also one or two oxygen from water and a carboxylate oxygen (Glu), for binding with Fe (or Ni) center.22
Genetic Engineering in Improving the Output of Algal Biorefinery
Published in Shashi Kant Bhatia, Sanjeet Mehariya, Obulisamy Parthiba Karthikeyan, Algal Biorefineries and the Circular Bioeconomy, 2022
Yogita Sharma, Ameesh Dev Singh, Sanjeet Mehariya, Obulisamy Parthiba Karthikeyan, Gajendra Pal Singh, Chandra Pal Singh, Antonio Molino
Amino acids are produced via the Shikimate pathway, which has also become an area of genetic engineering in algal biomass for bioprospecting amino acids (Mir et al., 2015). Several essential and non-essential amino acids with high nutritional and medicinal value have been reported from micro and marine algal species (Christaki et al., 2011; Smith, 1955; Fattorusso 2012). DAHP synthase, 3-dehydroquianate synthase, shikimate-5-dehydrogenase, shikimate kinase, and chorismate synthase (Tzin and Galili, 2010) are some of the critical enzymes in this pathway that can be targeted for genetic engineering for amino acid synthesis. Brey et al. (2020) in their study on Synechocystis sp. PCC6803 demonstrated the overproduction of phenylalanine and tyrosine by heterologous expression of enzymes AroG and TyrA from E. coli, resistant to feedback-inhibition during amino acid synthesis. The protein titers exhibited 580 ± 34mg/L of phenylalanine and 41 ± 2.3mg/L of tyrosine following 10 days of photo-autotrophic growth (Brey et al., 2020). Conclusively, these findings prove that amino acid pathway enzymes can also be genetically manipulated in algae and cyanobacteria for the overproduction of proteins. Taurine is another important amino acid required in several biological processes and has antioxidant and membrane stabilizing properties; thus, it is a popular ingredient in the human diet, animal feed, and even aquaculture feed. An engineered C. reinhardtii was designed that could overexpress cysteine dioxygenase/cysteine sulfinic acid decarboxylase (CDO/CSAD) for enhanced taurine levels that were otherwise poorly expressed in the microalga and yielded three times more taurine than wild type (Tevatia et al., 2019).
Mechanism of Ni(Fe)ARD action in methionine salvage pathway, in biosynthesis of ethylene, and role of Tyr-fragment as regulatory factor
Published in A. K. Haghi, Lionello Pogliani, Eduardo A. Castro, Devrim Balköse, Omari V. Mukbaniani, Chin Hua Chia, Applied Chemistry and Chemical Engineering, 2017
Ludmila I. Matienko, Larisa A. Mosolova, Vladimir I. Binyukov, Elena M. Mil, Gennady E. Zaikov
Both enzymes Ni(Fe)-ARD are members of the structural super family, known as cupins, which also include Fe-acetyl acetone dioxygenase (Dke1)2, 3 and cysteine dioxygenase. These family of cupins use a triad of histidineligands (His), and also one or two oxygens from water and a carboxylate oxygen (Glu), for binding with Fe (Ni)-center.2 Being the members of structural super family of cupins, the Ni(Fe)-ARDs present the unusual case of catalysis, as differ in the mechanism of action in relation to general substrates (1,2-dihydroxy-3-oxo-5 (methylthio)pent-1-ene (acireductone) and dioxygen).
Kinetic investigations of the formation of iron(IV) oxido complexes
Published in Journal of Coordination Chemistry, 2022
Florian J. Ritz, Markus Lerch, Jonathan Becker, Siegfried Schindler
Chromium complexes can be used to model the reactivity of iron enzymes. For example Nam and co-workers reported a chromium(III) superoxido complex that was applied as a biomimetic model compound for the proposed iron superoxido species in the active site of cysteine dioxygenase [30]. Furthermore, TMG3tren is quite useful to stabilize otherwise reactive “dioxygen adduct" complexes. Thus we had applied TMG3tren to obtain the first end-on-superoxido copper complex that could be structurally characterized [13]. Superoxides are related to ozonides and alkali ozonides can be synthetically prepared from alkali superoxides by reacting them with ozone [23, 24]. With this background we thought it could be possible to obtain an ozonido chromium(III) complex from the reaction of ozone with a corresponding chromium(II) complex. Chromium(III) complexes are kinetically inert and therefore it seemed likely that such an intermediate could be stable enough to isolate it prior to its further reaction to an oxido complex.