Role of Proximal Methionine Residues in Leishmania Major Peroxidase
IR@IICB: CSIR-Indian Institute of Chemical Biology, Kolkata
View Archive Info| Field | Value | |
| Title |
Role of Proximal Methionine Residues in Leishmania Major Peroxidase
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| Creator |
Yadav, Rajesh K
Pal, Swati Dolai, Subhankar Adak, Subrata |
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| Subject |
Structural Biology & Bioinformatics
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| Description |
The active site architecture of Leishmania major peroxidase (LmP) is very similar with both cytochrome c
peroxidase and ascorbate peroxidase. We utilized point mutagenesis to investigate if the conserved proximal
methionine residues (Met248 and Met249) in LmP help in controlling catalysis. Steady-state kinetics
of methionine mutants shows that ferrocytochrome c oxidation is <2% of wild type levels without affecting
the second order rate constant of first phase of Compound I formation, while the activity toward a
small molecule substrate, guaiacol or iodide, increases. Our diode array stopped-flow spectral studies
show that the porphyrin p-cation radical of Compound I in mutant LmP is more stable than wild type
enzyme. These results suggest that the electronegative sulfur atoms of the proximal pocket are critical
factors for controlling the location of a stable Compound I radical in heme peroxidases and are important
in the oxidation of ferrocytochrome c.
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| Date |
2011
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| Type |
Article
PeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://www.eprints.iicb.res.in/1009/1/abb2011.pdf
Yadav, Rajesh K and Pal, Swati and Dolai, Subhankar and Adak, Subrata (2011) Role of Proximal Methionine Residues in Leishmania Major Peroxidase. Archives of Biochemistry and Biophysics, 512. pp. 21-27. |
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| Relation |
http://dx.doi.org/10.1016/j.abb.2011.08.007
http://www.eprints.iicb.res.in/1009/ |
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