PDBsum entry 1gxw

Hydrolase

PDB id: 1gxw

Contents

Protein chain

316 a.a. *

Ligands

VAL-LYS

SCN

Metals

_CA ×4

_ZN

Waters ×170

* Residue conservation analysis

PDB id:

1gxw

Name:

Hydrolase

Title:

The 2.2 a resolution structure of thermolysin crystallized in presence of potassium thiocyanate

Structure:

Thermolysin. Chain: a. Ec: 3.4.24.27

Source:

Bacillus thermoproteolyticus. Organism_taxid: 1427

Biol. unit:

Monomer (from PDB file)

Resolution:

2.18Å R-factor: 0.163 R-free: 0.215

Authors:

J.F.Gaucher,M.Selkti,T.Prange,A.Tomas

Key ref:

J.F.Gaucher et al. (2002). The 2.2 A resolution structure of thermolysin (TLN) crystallized in the presence of potassium thiocyanate. Acta Crystallogr D Biol Crystallogr, 58, 2198-2200. PubMed id: 12454500 DOI: 10.1107/S0907444902015457

Date:

12-Apr-02 Release date: 05-Dec-02

Protein chain

P00800  (THER_BACTH) -  Thermolysin from Bacillus thermoproteolyticus

Seq: 548 a.a.

Struc: 316 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.3.4.24.27 - thermolysin.
• Reaction: Preferential cleavage: Xaa-|-Leu > Xaa-|-Phe.
• Cofactor: Ca(2+); Zn(2+)

DOI no: 10.1107/S0907444902015457

Acta Crystallogr D Biol Crystallogr 58:2198-2200 (2002)

PubMed id: 12454500

The 2.2 A resolution structure of thermolysin (TLN) crystallized in the presence of potassium thiocyanate.

J.F.Gaucher, M.Selkti, T.Prangé, A.Tomas.

ABSTRACT

A new crystallization protocol for thermolysin (EC 3.4.24.27) from Bacillus thermoproteolyticus is presented. After dissolving the protein in the presence of KSCN, which avoids the use of DMSO and CsCl, crystals were obtained following the salting-in method. Crystal cell parameters are isomorphous with those previously reported from DMSO/CsCl mixtures. The new SCN(-) crystal structure has been analyzed. It shows the presence of one thiocyanate ion in the catalytic site and several rearrangements in the S(1) and S(2) subsites. These results are in agreement with the measurements of Inouye et al. [(1998), J. Biochem. (Tokyo), 123, 847-852], who observed in solution that the solubility of TLN, which is particularly poor in low ionic strength solutions, increases dramatically in the presence of several neutral salts. The results reported here suggest possible explanations for the solubility increase and for the inhibitory effects of high SCN(-) concentrations on thermolysin activity.

Selected figure(s)

Figure 1.
Figure 1 Stereoimages illustrating the mode of binding of the SCN ion to TLN and the rearrangement of the subsite S1-S2. (a) Partial structure of the active site of TLN crystallized in the presence of DMSO/CsCl. (b) Partial structure of the same active site of TLN crystallized in the presence of KSCN. Tyr157 rotates about the [1] angle toward Asp150. The SCN ion tightly binds His231, Glu166 and a water molecule (VMD; Humphrey et al., 1996[Humphrey, W., Dalke, A. & Schulten, K. (1996). J. Mol. Graph. 14, 33-38, 27-28.]).

The above figure is reprinted by permission from the IUCr: Acta Crystallogr D Biol Crystallogr (2002, 58, 2198-2200) copyright 2002.