4R9I

Crystal structure of cysteine proteinase inhibitor Serpin18 from Bombyx mori


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.65 Å
  • R-Value Free: 0.207 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.179 

wwPDB Validation 3D Report Full Report



Literature

Structural insights into the unique inhibitory mechanism of the silkworm protease inhibitor serpin18

Guo, P.C.Dong, Z.Zhao, P.Zhang, Y.He, H.W.Tan, X.Zhang, W.Xia, Q.Y.

(2015) Sci Rep 5: 11863-11863

  • DOI: 10.1038/srep11863
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Serpins generally serve as inhibitors that utilize a mobile reactive center loop (RCL) as bait to trap protease targets. Here, we present the crystal structure of serpin18 from Bombyx mori at 1.65 Å resolution, which has a very short and stable RCL. ...

    Serpins generally serve as inhibitors that utilize a mobile reactive center loop (RCL) as bait to trap protease targets. Here, we present the crystal structure of serpin18 from Bombyx mori at 1.65 Å resolution, which has a very short and stable RCL. Activity analysis showed that the inhibitory target of serpin18 is a cysteine protease rather than a serine protease. Notably, this inhibitiory reaction results from the formation of an intermediate complex, which then follows for the digestion of protease and inhibitor into small fragments. This activity differs from previously reported modes of inhibition for serpins. Our findings have thus provided novel structural insights into the unique inhibitory mechanism of serpin18. Furthermore, one physiological target of serpin18, fibroinase, was identified, which enables us to better define the potential role for serpin18 in regulating fibroinase activity during B. mori development.


    Organizational Affiliation

    State Key Laboratory of Silkworm Genome Biology, Southwest University, 216, Tiansheng Road, Beibei, Chongqing 400716, People's Republic of China.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Serpin-18
A
378Bombyx moriMutation(s): 0 
Find proteins for C0J8G7 (Bombyx mori)
Go to UniProtKB:  C0J8G7
Protein Feature View
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FLC
Query on FLC

Download CCD File 
A
CITRATE ANION
C6 H5 O7
KRKNYBCHXYNGOX-UHFFFAOYSA-K
 Ligand Interaction
BME
Query on BME

Download CCD File 
A
BETA-MERCAPTOETHANOL
C2 H6 O S
DGVVWUTYPXICAM-UHFFFAOYSA-N
 Ligand Interaction
NA
Query on NA

Download CCD File 
A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.65 Å
  • R-Value Free: 0.207 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.179 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 109.301α = 90
b = 109.301β = 90
c = 72.545γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
SOLVEphasing
REFMACrefinement
HKL-3000data reduction
HKL-3000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-09-09
    Type: Initial release