scholarly journals Biochemical characterization of the purple form of Marinobacter hydrocarbonoclasticus nitrous oxide reductase

2012 ◽  
Vol 367 (1593) ◽  
pp. 1204-1212 ◽  
Author(s):  
Simone Dell'Acqua ◽  
Sofia R. Pauleta ◽  
José J. G. Moura ◽  
Isabel Moura
Keyword(s):  
Nitrous Oxide ◽  
Redox State ◽  
Biochemical Characterization ◽  
Specific Activity ◽  
Active Species ◽  
Nitrous Oxide Reductase ◽  
Strictly Anaerobic ◽  
Prolonged Incubation ◽  
Redox Active ◽  
Marinobacter Hydrocarbonoclasticus

Nitrous oxide reductase (N 2 OR) catalyses the final step of the denitrification pathway—the reduction of nitrous oxide to nitrogen. The catalytic centre (CuZ) is a unique tetranuclear copper centre bridged by inorganic sulphur in a tetrahedron arrangement that can have different oxidation states. Previously, Marinobacter hydrocarbonoclasticus N 2 OR was isolated with the CuZ centre as CuZ*, in the [1Cu 2+ : 3Cu + ] redox state, which is redox inert and requires prolonged incubation under reductive conditions to be activated. In this work, we report, for the first time, the isolation of N 2 OR from M. hydrocarbonoclasticus in the ‘purple’ form, in which the CuZ centre is in the oxidized [2Cu 2+ : 2Cu + ] redox state and is redox active. This form of the enzyme was isolated in the presence of oxygen from a microaerobic culture in the presence of nitrate and also from a strictly anaerobic culture. The purple form of the enzyme was biochemically characterized and was shown to be a redox active species, although it is still catalytically non-competent, as its specific activity is lower than that of the activated fully reduced enzyme and comparable with that of the enzyme with the CuZ centre in either the [1Cu 2+ : 3Cu + ] redox state or in the redox inactive CuZ* state.

Biochemical characterization and solution structure of nitrous oxide reductase from Alcaligenes xylosoxidans (NCIMB 11015)

2001 ◽  
Vol 259 (3) ◽  
pp. 651-659 ◽  
Author(s):  
Silvia Ferretti ◽  
J. Günter Grossmann ◽  
S. Samar Hasnain ◽  
Robert R. Eady ◽  
Barry E. Smith
Keyword(s):  
Nitrous Oxide ◽  
Solution Structure ◽  
Biochemical Characterization ◽  
Nitrous Oxide Reductase

scholarly journals Protonation state of the Cu4S2CuZsite in nitrous oxide reductase: redox dependence and insight into reactivity

2015 ◽  
Vol 6 (10) ◽  
pp. 5670-5679 ◽  
Author(s):  
Esther M. Johnston ◽  
Simone Dell'Acqua ◽  
Sofia R. Pauleta ◽  
Isabel Moura ◽  
Edward I. Solomon
Keyword(s):  
Electron Transfer ◽  
Nitrous Oxide ◽  
Redox State ◽  
Nitrous Oxide Reductase ◽  
Protonation State ◽  
Proton Coupled Electron Transfer ◽  
Insight Into

The edge ligand in the Cu4S2CuZform of nitrous oxide reductase is a μ2-thiolate in the 1-hole and a μ2-sulfide in the 2-hole redox state, leading to proton-coupled electron transfer reactivity.

scholarly journals The effect of pH on Marinobacter hydrocarbonoclasticus denitrification pathway and nitrous oxide reductase

2020 ◽  
Vol 25 (7) ◽  
pp. 927-940 ◽  
Author(s):  
Cíntia Carreira ◽  
Rute F. Nunes ◽  
Olga Mestre ◽  
Isabel Moura ◽  
Sofia R. Pauleta
Keyword(s):  
Nitrous Oxide ◽  
Nitrous Oxide Reductase ◽  
Effect Of Ph ◽  
Marinobacter Hydrocarbonoclasticus

Nature’s way of handling a greenhouse gas: the copper-sulfur cluster of purple nitrous oxide reductase

2012 ◽  
Vol 393 (10) ◽  
pp. 1067-1077 ◽  
Author(s):  
Anja Wüst ◽  
Lisa Schneider ◽  
Anja Pomowski ◽  
Walter G. Zumft ◽  
Peter M.H. Kroneck ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Paracoccus Denitrificans ◽  
Copper Ions ◽  
Bacterial Species ◽  
Three Dimensional ◽  
Pseudomonas Stutzeri ◽  
Structural Data ◽  
Nitrous Oxide Reductase ◽  
Bridging Ligand ◽  
Marinobacter Hydrocarbonoclasticus

Abstract The tetranuclear CuZ cluster is the unique active site of nitrous oxide reductase, the enzyme that catalyzes the reduction of nitrous oxide to dinitrogen as the final reaction in bacterial denitrification. Three-dimensional structures of orthologs of the enzyme from a variety of different bacterial species were essential steps in the elucidation of the properties of this center. However, while structural data first revealed and later confirmed the presence of four copper ions in spectroscopically distinct forms of CuZ, the exact structure and stoichiometry of the cluster showed significant variations. A ligand bridging ions CuZ1 and CuZ2 was initially assigned as a water or hydroxo species in the structures from Pseudomonas nautica (now Marinobacter hydrocarbonoclasticus) and Paracoccus denitrificans. This ligand was absent in a structure from ‘Achromobacter cycloclastes’, and could be reconstituted by iodide that acted as an inhibitor of catalysis. A recent structure of anoxically isolated nitrous oxide reductase from Pseudomonas stutzeri revealed the bridging ligand to be sulfide, S2-, and showed an unprecedented side-on mode of nitrous oxide binding to this form of CuZ.

scholarly journals Biochemical characterization of specific Alanine Decarboxylase (AlaDC) and its ancestral enzyme Serine Decarboxylase (SDC) in tea plants (Camellia sinensis)

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Peixian Bai ◽  
Liyuan Wang ◽  
Kang Wei ◽  
Li Ruan ◽  
Liyun Wu ◽  
...  
Keyword(s):  
Gene Duplication ◽  
Camellia Sinensis ◽  
Biochemical Characterization ◽  
Specific Activity ◽  
Protein Sequences ◽  
Biochemical Properties ◽  
High Similarity ◽  
New Gene ◽  
Tea Plants

Abstract Background Alanine decarboxylase (AlaDC), specifically present in tea plants, is crucial for theanine biosynthesis. Serine decarboxylase (SDC), found in many plants, is a protein most closely related to AlaDC. To investigate whether the new gene AlaDC originate from gene SDC and to determine the biochemical properties of the two proteins from Camellia sinensis, the sequences of CsAlaDC and CsSDC were analyzed and the two proteins were over-expressed, purified, and characterized. Results The results showed that exon-intron structures of AlaDC and SDC were quite similar and the protein sequences, encoded by the two genes, shared a high similarity of 85.1%, revealing that new gene AlaDC originated from SDC by gene duplication. CsAlaDC and CsSDC catalyzed the decarboxylation of alanine and serine, respectively. CsAlaDC and CsSDC exhibited the optimal activities at 45 °C (pH 8.0) and 40 °C (pH 7.0), respectively. CsAlaDC was stable under 30 °C (pH 7.0) and CsSDC was stable under 40 °C (pH 6.0–8.0). The activities of the two enzymes were greatly enhanced by the presence of pyridoxal-5′-phosphate. The specific activity of CsSDC (30,488 IU/mg) was 8.8-fold higher than that of CsAlaDC (3467 IU/mg). Conclusions Comparing to CsAlaDC, its ancestral enzyme CsSDC exhibited a higher specific activity and a better thermal and pH stability, indicating that CsSDC acquired the optimized function after a longer evolutionary period. The biochemical properties of CsAlaDC might offer reference for theanine industrial production.

Sign in / Sign up

Export Citation Format

Share Document