Crystal structure of thioredoxin domain of ST2123 from thermophilic archaea Sulfolobus tokodaii strain7

Single-molecule paleoenzymology probes the chemistry of resurrected enzymes

“…It is interesting to compare the acid tolerance of the resurrected enzymes with enzymes from extant extremophiles. For example, Trx from Sulfolobus tokodaii (thermophilic archaea33), with a melting temperature of 122° C (Supplementary Fig. 7), is active at pH 7 (0.12×10 5 M −1 s −1 at 50 pN), but does not show detectable activity at pH 5 (Fig.…”

The dimeric structure of Sulfolobus solfataricus thioredoxin A2 and the basis of its thermostability

“…1(A)]. Notably, Ss TrxA2 monomer shows also significant differences when it is compared to St Trx monomer9 (RMSD of 0.72 Å), despite the high sequence identity (73%) of the two proteins [Fig. 1(A)].…”

“…Here we report a structural characterization of Ss TrxA2 (sequence entry Q97WI4). Although this protein shows an elevated level of sequence identity (73%) with a thioredoxin isolated from S. tokodaii ( St Trx), whose structure has been recently determined,9 the two proteins exhibit a different oligomeric state, being St Trx monomeric9 and Ss TrxA2 dimeric 6. The structural characterization of very similar proteins which display different quaternary structures is a topic of remarkable interest for understanding the process of protein oligomerization 10, 11.…”

Crystallographic and spectroscopic characterizations of Sulfolobus solfataricus TrxA1 provide insights into the determinants of thioredoxin fold stability

“…Although these analyses have unveiled that no mechanism has a general validity, it seems that an important role in protein stabilization is played by the occurrence of salt bridges (Kumar et al, 2000;Kumar and Nussinov, 2004). Moreover, previous studies have suggested that electrostatic interactions may be responsible for the remarkable stability of StTrx (Ming et al, 2007). As SsTrxA1 is endowed with a remarkable thermal stability (see also below) we carried out a detailed analysis of the ion pairs in SsTrxA1.…”

“…The comparison of SsTrxA1 with SsTrxA2 (Ruggiero et al, 2009a) and Trxs isolated from Sulfolobus tokodaii (StTrx) (Ming et al, 2007), Escherichia coli (EcTrx) (Katti et al, 1990), Thermus thermophilus (TtTrx) (Yanai, H., Yokoyama, S., Kuramitsu, S. PDB code 2CVK), and spinach chloroplast M (SpTrx) (Capitani et al, 2000) yields root mean square deviation (RMSD) values in the range of 0.74-1.08 Å. This is in line with the sequence identity detected between SsTrxA1 and these Trxs (38-45%) (Fig.…”