P0DQT9 · DEF4_MESMA
- ProteinDefensin BmKDfsin4
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Dual-function peptide with antimicrobial and potassium channel-blocking activities (PubMed:26817841).
Shows inhibitory activity against Gram-positive bacteria such as S.aureus, B.subtilis, and M.luteus as well as methicillin-resistant S.aureus (MIC=0.1-20 uM) (PubMed:26817841).
Does not act on bacteria by disrupting membranes (PubMed:26817841).
Also moderately inhibits Kv1.1/KCNA1 (25.2% inhibition at 1 uM), Kv1.2/KCNA2 (30.5% inhibition at 1 uM), and Kv1.3/KCNA3 potassium channels (IC50=510.2 nM, 61% inhibition at 1 uM) (PubMed:26817841).
Inhibits potassium channels by interacting with the pore region (PubMed:26817841).
Does not show hemolytic activity (PubMed:27128943).
In vitro, dose-dependently decreases the production of Hepatitis B virus (HBV) DNA and HBV viral proteins in both culture medium and cell lysate (PubMed:27128943).
Shows inhibitory activity against Gram-positive bacteria such as S.aureus, B.subtilis, and M.luteus as well as methicillin-resistant S.aureus (MIC=0.1-20 uM) (PubMed:26817841).
Does not act on bacteria by disrupting membranes (PubMed:26817841).
Also moderately inhibits Kv1.1/KCNA1 (25.2% inhibition at 1 uM), Kv1.2/KCNA2 (30.5% inhibition at 1 uM), and Kv1.3/KCNA3 potassium channels (IC50=510.2 nM, 61% inhibition at 1 uM) (PubMed:26817841).
Inhibits potassium channels by interacting with the pore region (PubMed:26817841).
Does not show hemolytic activity (PubMed:27128943).
In vitro, dose-dependently decreases the production of Hepatitis B virus (HBV) DNA and HBV viral proteins in both culture medium and cell lysate (PubMed:27128943).
Miscellaneous
Negative results: has no inhibitory activity against Gram-negative bacteria (PubMed:26817841).
Shows very weak inhibition of the potassium currents mediated by the Kv11.1/KCNH2/ERG1 (11.6%), KCa3.1/KCNN4/IK/SK4 (3.9%), KCa2.3/KCNN3/SK3 (7%), Kv7/KCNQ (5.9%), when tested at 1 uM (PubMed:26817841).
Shows very weak inhibition of the potassium currents mediated by the Kv11.1/KCNH2/ERG1 (11.6%), KCa3.1/KCNN4/IK/SK4 (3.9%), KCa2.3/KCNN3/SK3 (7%), Kv7/KCNQ (5.9%), when tested at 1 uM (PubMed:26817841).
Features
Showing features for site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Site | 37 | Key residue in interaction with Kv1.3/KCNA3 | ||||
Sequence: K | ||||||
Site | 43 | Key residue in interaction with Kv1.3/KCNA3 | ||||
Sequence: R |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | extracellular region | |
Molecular Function | potassium channel regulator activity | |
Molecular Function | toxin activity | |
Biological Process | defense response to bacterium | |
Biological Process | innate immune response |
Keywords
- Molecular function
- Biological process
Names & Taxonomy
Protein names
- Recommended nameDefensin BmKDfsin4
- Alternative names
Organism names
- Taxonomic lineageEukaryota > Metazoa > Ecdysozoa > Arthropoda > Chelicerata > Arachnida > Scorpiones > Buthida > Buthoidea > Buthidae > Mesobuthus
Accessions
- Primary accessionP0DQT9
Subcellular Location
Phenotypes & Variants
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 37 | Important decrease in ability to block Kv1.3/KCNA3 potassium channel. | ||||
Sequence: K → A | ||||||
Mutagenesis | 43 | Important decrease in ability to block Kv1.3/KCNA3 potassium channel. | ||||
Sequence: R → A | ||||||
Mutagenesis | 44 | Moderate decrease in abmility to block Kv1.3/KCNA3 potassium channel. | ||||
Sequence: R → A | ||||||
Mutagenesis | 45 | Moderate decrease in ability to block Kv1.3/KCNA3 potassium channel. | ||||
Sequence: R → A | ||||||
Mutagenesis | 61 | Moderate decrease in ability to block Kv1.3/KCNA3 potassium channel. | ||||
Sequence: R → A |
PTM/Processing
Features
Showing features for signal, chain, disulfide bond.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Signal | 1-24 | |||||
Sequence: MKTIVLLFVLALVFCTLEMGIVEA | ||||||
Chain | PRO_0000455528 | 25-62 | Defensin BmKDfsin4 | |||
Sequence: GFGCPFNQGQCHKHCQSIRRRGGYCDGFLKQRCVCYRK | ||||||
Disulfide bond | 28↔49 | |||||
Sequence: CPFNQGQCHKHCQSIRRRGGYC | ||||||
Disulfide bond | 35↔57 | |||||
Sequence: CHKHCQSIRRRGGYCDGFLKQRC | ||||||
Disulfide bond | 39↔59 | |||||
Sequence: CQSIRRRGGYCDGFLKQRCVC |
Keywords
- PTM
Family & Domains
Domain
Has the structural arrangement of an alpha-helix connected to a beta-sheet by disulfide bonds (CSalpha/beta).
Sequence similarities
Belongs to the invertebrate defensin family. Type 2 subfamily.
Keywords
- Domain