scholarly journals Peroxygenase and Oxidase Activities of Dehaloperoxidase-Hemoglobin from Amphitrite ornata

2014 ◽  
Vol 136 (22) ◽  
pp. 7914-7925 ◽  
Author(s):  
David A. Barrios ◽  
Jennifer D’Antonio ◽  
Nikolette L. McCombs ◽  
Jing Zhao ◽  
Stefan Franzen ◽  
...  
Keyword(s):  
Amphitrite Ornata

scholarly journals Interaction of Azole-Based Environmental Pollutants with the Coelomic Hemoglobin from Amphitrite ornata: A Molecular Basis for Toxicity

Biochemistry ◽  
2017 ◽  
Vol 56 (17) ◽  
pp. 2294-2303 ◽  
Author(s):  
Nikolette L. McCombs ◽  
Tadeo Moreno-Chicano ◽  
Leiah M. Carey ◽  
Stefan Franzen ◽  
Michael A. Hough ◽  
...  
Keyword(s):  
Molecular Basis ◽  
Environmental Pollutants ◽  
Amphitrite Ornata

Amphitrite ornata erythrocruorin. I. Structural properties and characterization of subunit interactions

1980 ◽  
Vol 623 (1) ◽  
pp. 146-162 ◽  
Author(s):  
Emilia Chiancone ◽  
Michael Brenowitz ◽  
Franca Ascoli ◽  
Celia Bonaventura ◽  
Joseph Bonaventura
Keyword(s):  
Structural Properties ◽  
Subunit Interactions ◽  
Properties And Characterization ◽  
Amphitrite Ornata

Structures of K42N and K42Y sperm whale myoglobins point to an inhibitory role of distal water in peroxidase activity

2014 ◽  
Vol 70 (11) ◽  
pp. 2833-2839 ◽  
Author(s):  
Chunxue Wang ◽  
Leslie L. Lovelace ◽  
Shengfang Sun ◽  
John H. Dawson ◽  
Lukasz Lebioda
Keyword(s):  
Peroxidase Activity ◽  
Physiological Role ◽  
Sperm Whale ◽  
Reaction Rates ◽  
Heme Iron ◽  
Oxygen Storage ◽  
Dual Function ◽  
Amphitrite Ornata ◽  
Coordinated Water

Sperm whale myoglobin (Mb) functions as an oxygen-storage protein, but in the ferric state it possesses a weak peroxidase activity which enables it to carry out H2O2-dependent dehalogenation reactions. Hemoglobin/dehaloperoxidase fromAmphitrite ornata(DHP) is a dual-function protein represented by two isoproteins DHP A and DHP B; its peroxidase activity is at least ten times stronger than that of Mb and plays a physiological role. The `DHP A-like' K42Y Mb mutant (K42Y) and the `DHP B-like' K42N mutant (K42N) were engineered in sperm whale Mb to mimic the extended heme environments of DHP A and DHP B, respectively. The peroxidase reaction rates increased ∼3.5-fold and ∼5.5-fold in K42Y and K42NversusMb, respectively. The crystal structures of the K42Y and K42N mutants revealed that the substitutions at position 42 slightly elongate not only the distances between the distal His55 and the heme iron but also the hydrogen-bonding distances between His55 and the Fe-coordinated water. The enhanced peroxidase activity of K42Y and K42N thus might be attributed in part to the weaker binding of the axial water molecule that competes with hydrogen peroxide for the binding site at the heme in the ferric state. This is likely to be the mechanism by which the relationship `longer distal histidine to Fe distance – better peroxidase activity', which was previously proposed for heme proteins by Matsuiet al.(1999) (J. Biol. Chem.274, 2838–2844), works. Furthermore, positive cooperativity in K42N was observed when its dehaloperoxidase activity was measured as a function of the concentration of the substrate trichlorophenol. This serendipitously engineered cooperativity was rationalized by K42N dimerization through the formation of a dityrosine bond induced by excess H2O2.

scholarly journals Structural Probes Of Reactive Intermediates Of Dehaloperoxidase From Amphitrite ornata

2009 ◽  
Vol 96 (3) ◽  
pp. 558a
Author(s):  
Stefan Franzen ◽  
Vesna de Serrano ◽  
Michael F. Davis ◽  
Matt Thompson
Keyword(s):  
Reactive Intermediates ◽  
Amphitrite Ornata ◽  
Structural Probes

Amphitrite ornata dehaloperoxidase: enhanced activity for the catalytically active globin using MCPBA

2004 ◽  
Vol 324 (4) ◽  
pp. 1194-1198 ◽  
Author(s):  
Robert L. Osborne ◽  
Laurie O. Taylor ◽  
Kai Ping Han ◽  
Bert Ely ◽  
John H. Dawson
Keyword(s):  
Enhanced Activity ◽  
Amphitrite Ornata ◽  
Catalytically Active
Sign in / Sign up

Export Citation Format

Share Document