General Information

General Information

DRAVP ID DRAVPe00279

Peptide Name Circulin-B (CIRB; Plant defensin)

Sequence GVIPCGESCVFIPCISTLLGCSCKNKVCYRN

Sequence Length 31

UniProt ID P56879

Source Chassalia parviflora

Activity Information

Target Organism HIV

Assay

Activity

[Ref.18008336]HIV-1:inhibition the cytopathic effects of HIV-1 infection in cultured human T-lymphoblast (CEM-SS) cells(EC50=40-260 nM).

Hemolytic Activity

[Ref.10430870] EC50 = 550 μM against blood type A human erythrocytes.

Cytotoxicity

[Ref.10430870] It caused 50% cell growth inhibition of mouse fibroblasts at 820 μM.
[Ref.18008336]CEM-SS cells:IC50=500 nM.

Binding Target Not found

Mechanism No machanism information found in the reference(s) presented in this entry

Structure Information

PDB ID 2ERI

Predicted Structure Download DRAVPe00279

Linear/Cyclic Cyclic

N-terminal Modification Cyclization (N termini to C termini)

C-terminal Modification Cyclization (C termini to N termini)

Other Modification Disulfide bonds between Cys5 and Cys19, Cys9 and Cys21, Cys14 and Cys27.

Stereochemistry L

Physicochemical Information

Formula C141H232N38O41S6

Absent amino acids ADHMQW

Common amino acids C

Mass 3307.98

Pl 8.33

Basic residues 3

Acidic residues 1

Hydrophobic residues 9

Net charge 2

Boman Index -882

Hydrophobicity 64.19

Aliphatic Index 90.97

Half Life

Mammalian:30 hour
Yeast:>20 hour
E.coli:>10 hour

Extinction Coefficient cystines 1865

Absorbance 280nm 62.17

Polar residues 16

Literature Information

Literature 1

Title Cyclotides as natural anti-HIV agents.

Pubmed ID 18008336

Reference Biopolymers. 2008;90(1):51-60.

Author Ireland DC, Wang CK, Wilson JA, Gustafson KR, Craik DJ.

DOI 10.1002/bip.20886

Literature 2

Title An unusual structural motif of antimicrobial peptides containing end-to-end macrocycle and cystine-knot disulfides.

Pubmed ID 10430870

Reference Proc Natl Acad Sci U S A. 1999 Aug 3;96(16):8913-8.

Author Tam JP, Lu YA, Yang JL, Chiu KW.

DOI 10.1073/pnas.96.16.8913