کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1926838 1536484 2008 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The dimeric assembly of Photobacterium leiognathi and Salmonella typhimurium SodC1 Cu,Zn superoxide dismutases is affected differently by active site demetallation and pH: An analytical ultracentrifuge study
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
The dimeric assembly of Photobacterium leiognathi and Salmonella typhimurium SodC1 Cu,Zn superoxide dismutases is affected differently by active site demetallation and pH: An analytical ultracentrifuge study
چکیده انگلیسی

To establish whether the species-specific variations at the subunit interface of bacterial Cu,Zn superoxide dismutases affect dimer assembly, the association state of the Photobacterium leiognathi (PlSOD) and Salmonella typhimurium (StSOD) enzymes, which differ in 11 out of 19 interface residues, was investigated by analytical ultracentrifugation.The same linkage pattern correlates quaternary assembly, active site metallation, and pH in the two enzymes albeit with quantitative differences. Both holo-enzymes are stable dimers at pH 6.8 and 8.0, although their shape is altered at alkaline pH. In contrast, dimer stability is affected differently by metal removal. Thus, apo-StSOD is a stable dimer at pH 6.8 whereas apo-PlSOD is in reversible monomer–dimer equilibrium. In both apoproteins a pH increase to 8.0 favors monomerization. These effects prove the existence of long-range communication between the active site and the subunit interface and provide a structural explanation for the known functional differences between the two enzymes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Archives of Biochemistry and Biophysics - Volume 471, Issue 1, 1 March 2008, Pages 77–84
نویسندگان
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