Thiole und Thioredoxine

Abstract

Wie werden Dutzende unterschiedlicher Stoffwechselreaktionen mit S‐S‐/SH‐Redoxwechsel in und außerhalb von Zellen durch kleine Dicysteinproteine hinsichtlich Spezifität, Richtung und Regulation differenziert? Antworten gab die erstmals in Deutschland veranstaltete Konferenz über Thioredoxine, Glutaredoxine und verwandte Proteine.

A hypothesis on the catalytic mechanism of the selenoenzyme thioredoxin reductase

“…Thioredoxin reductase (EC 1.6.4.5), like lipoamide dehydrogenase, mercuric reductase and glutathione reductase, is a member of the pyridine nucleotide-disulphide oxidoreductase family of dimeric flavoenzymes [1]. It catalyses the NADPH-dependent reduction of the 12 kDa protein thioredoxin [NADPHj H + jthioredoxin-S # NADP + jthioredoxin-(SH) # ], which provides reducing equivalents for processes like the reduction of ribonucleotides to deoxyribonucleotides by ribonucleotide reductase [2] and is also considered as a pleiotropic regulator of the cellular redox balance [3,4]. The sequences, sizes and catalytic mechanisms of thioredoxin reductases are different between prokaryotes, such as Escherichia coli, and mammals [5,6].…”