PDBsum entry 6ycc

Hydrolase

PDB id: 6ycc

Contents

Protein chains

215 a.a.

Ligands

E64 ×2

SO4 ×4

GOL ×3

Waters ×447

PDB id:

6ycc

Name:

Hydrolase

Title:

Structure the ananain protease from ananas comosus covalently bound to the e64 inhibitor

Structure:

Ananain. Chain: a, b. Ec: 3.4.22.31

Source:

Ananas comosus. Pineapple. Organism_taxid: 4615

Resolution:

1.30Å R-factor: 0.145 R-free: 0.169

Authors:

M.Azarkan,P.Charlier,R.Herman,F.Delbrassine,E.Sauvage,N.M Rabet, R.Calvo Esposito,F.Kerff

Key ref:

M.Azarkan et al. (2020). Structures of the free and inhibitors-bound forms of bromelain and ananain from Ananas comosus stem and in vitro study of their cytotoxicity. Sci Rep, 10, 19570. PubMed id: 33177555 DOI: 10.1038/s41598-020-76172-5

Date:

18-Mar-20 Release date: 25-Nov-20

Protein chains

P80884  (ANAN_ANACO) -  Ananain from Ananas comosus

Seq: 345 a.a.

Struc: 215 a.a.

Enzyme reactions

• Enzyme class: E.C.3.4.22.31 - ananain.
• Reaction: Hydrolysis of proteins with broad specificity for peptide bonds. Best reported small molecule substrate Bz-Phe-Val-Arg-|-NHMec, but broader specificity than fruit bromelain.

DOI no: 10.1038/s41598-020-76172-5

Sci Rep 10:19570 (2020)

PubMed id: 33177555

Structures of the free and inhibitors-bound forms of bromelain and ananain from Ananas comosus stem and in vitro study of their cytotoxicity.

M.Azarkan, E.Maquoi, F.Delbrassine, R.Herman, N.M'Rabet, R.Calvo Esposito, P.Charlier, F.Kerff.

ABSTRACT

The Ananas comosus stem extract is a complex mixture containing various cysteine ​​proteases of the C1A subfamily, such as bromelain and ananain. This mixture used for centuries in Chinese medicine, has several potential therapeutic applications as anti-cancer, anti-inflammatory and ecchymosis degradation agent. In the present work we determined the structures of bromelain and ananain, both in their free forms and in complex with the inhibitors E64 and TLCK. These structures combined with protease-substrate complexes modeling clearly identified the Glu68 as responsible for the high discrimination of bromelain in favor of substrates with positively charged residues at P2, and unveil the reasons for its weak inhibition by cystatins and E64. Our results with purified and fully active bromelain, ananain and papain show a strong reduction of cell proliferation with MDA-MB231 and A2058 cancer cell lines at a concentration of about 1 μM, control experiments clearly emphasizing the need for proteolytic activity. In contrast, while bromelain and ananain had a strong effect on the proliferation of the OCI-LY19 and HL-60 non-adherent cell lines, papain, the archetypal member of the C1A subfamily, had none. This indicates that, in this case, sequence/structure identity beyond the active site of bromelain and ananain is more important than substrate specificity.