PDBsum entry 1ylc

Hydrolase/inhibitor

PDB id: 1ylc

Contents

Protein chains

223 a.a. *

56 a.a. *

Ligands

SO4 ×2

Metals

_CA

Waters ×227

* Residue conservation analysis

PDB id:

1ylc

Name:

Hydrolase/inhibitor

Title:

Trypsin/bpti complex mutant

Structure:

Trypsin ii. Chain: a. Engineered: yes. Mutation: yes. Pancreatic trypsin inhibitor. Chain: b. Synonym: basic protease inhibitor, bpi, bpti, aprotinin. Engineered: yes. Mutation: yes

Source:

Rattus norvegicus. Norway rat. Organism_taxid: 10116. Gene: try2. Expressed in: escherichia coli. Expression_system_taxid: 562. Synthetic: yes. Other_details: 5,30,51,55 abu

Biol. unit:

Dimer (from PQS)

Resolution:

1.70Å R-factor: 0.197 R-free: 0.224

Authors:

C.K.Brown,D.H.Ohlendorf

Key ref:

I.V.Getun et al. (2008). Partially folded bovine pancreatic trypsin inhibitor analogues attain fully native structures when co-crystallized with S195A rat trypsin. J Mol Biol, 375, 812-823. PubMed id: 18054043 DOI: 10.1016/j.jmb.2007.10.084

Date:

19-Jan-05 Release date: 25-Apr-06

Protein chain

P00763  (TRY2_RAT) -  Anionic trypsin-2 from Rattus norvegicus

Seq: 246 a.a.

Struc: 223 a.a.*

Protein chain

P00974  (BPT1_BOVIN) -  Pancreatic trypsin inhibitor from Bos taurus

Seq: 100 a.a.

Struc: 56 a.a.*

* PDB and UniProt seqs differ at 5 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chain A: E.C.3.4.21.4 - trypsin.
• Reaction: Preferential cleavage: Arg-|-Xaa, Lys-|-Xaa.

DOI no: 10.1016/j.jmb.2007.10.084

J Mol Biol 375:812-823 (2008)

PubMed id: 18054043

Partially folded bovine pancreatic trypsin inhibitor analogues attain fully native structures when co-crystallized with S195A rat trypsin.

I.V.Getun, C.K.Brown, J.Tulla-Puche, D.Ohlendorf, C.Woodward, G.Barany.

ABSTRACT

Crystal structures, at 1.7 A resolution, were solved for complexes between each of two chemically synthesized partially folded analogues of bovine pancreatic trypsin inhibitor (BPTI) with the proteolytically inactive rat trypsin mutant S195A. The BPTI analogue termed [14-38](Abu) retains only the disulfide bond between Cys14 and Cys38, while Cys5, Cys30, Cys51, and Cys55 are replaced by isosteric alpha-amino-n-butyric acid residues. The analogue K26P,A27D[14-38](Abu) contains two further replacements, by statistically favored residues, in the type I beta-turn that has been suggested to be a main site for initiation of BPTI folding. As a control, the structure of the complex between S195A trypsin and wild-type BPTI was also solved. Despite significant differences in the degree of structure detected among these three BPTIs in solution by several biophysical techniques, their tertiary folds once bound to S195A trypsin in a crystalline lattice are essentially superimposable.

Selected figure(s)

Figure 4.
Fig. 4. Positions of BPTI internal waters 500, 512, 522, 525, and 529 in the complexes of S195A trypsin with wild-type BPTI (cyan), with [14–38][Abu] (blue), and with K26P,A27D[14–38][Abu] (magenta).

Figure 5.
Fig. 5. 2F[o] − F[c] density in the S195A trypsin–wild-type BPTI complex around the 30–51 disulfide (pink) and corresponding 2F[o] − F[c] density in the S195A trypsin–K26P,A27D[14–38][Abu] complex around the paired Abu residues (white).

The above figures are reprinted by permission from Elsevier: J Mol Biol (2008, 375, 812-823) copyright 2008.

Figures were selected by an automated process.