کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2048537 1074083 2011 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Conversion of a decarboxylating to a non-decarboxylating glutaryl-coenzyme A dehydrogenase by site-directed mutagenesis
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش گیاه شناسی
پیش نمایش صفحه اول مقاله
Conversion of a decarboxylating to a non-decarboxylating glutaryl-coenzyme A dehydrogenase by site-directed mutagenesis
چکیده انگلیسی

Glutaryl-coenzyme A (CoA) dehydrogenases (GDHs) are acyl-CoA dehydrogenases, which usually dehydrogenate and decarboxylate the substrate to crotonyl-CoA. In some anaerobic bacteria, non-decarboxylating GDHs exist that release glutaconyl-CoA (2,3-dehydroglutaryl-CoA) without decarboxylation. The differing mechanisms of decarboxylating and non-decarboxylating GDHs were investigated by site-directed mutagenesis of the gene coding for the crotonyl-CoA-forming GDH from Geobacter metallireducens. Exchange of single amino acids involved in substrate carboxylate binding impaired the decarboxylation step, resulting in relative glutaconyl-CoA:crotonyl-CoA formation rates of 1:1 (S97A) or 13:1 (Y370A). The total amount of glutaconyl-CoA formed was maximal in the Y370V+S97A double mutant. The results obtained indicate that an invariant deprotonated Tyr plays a crucial role for optimizing the leaving group potential of CO2 in decarboxylating GDHs.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: FEBS Letters - Volume 585, Issue 9, 6 May 2011, Pages 1317–1321
نویسندگان
, , , ,