mastoparan-B

CHEBI:78511 ·resolve ·ANTIBACTERIAL ·EXACT SEEDED

A member of the class of mastopyrans that is a 14-amino acid polypeptide comprising leucyl, lysyl, leucyl, lysyl, seryl, isoleucyl, valyl, seryl, tryptophyl, alanyl, lysyl, lysyl, valyl, and leucinamide residues coupled in sequence. It is the major active component of the venom of the hornet Vespa basalis and causes degranulation of mast cells. It exhibits antimicrobial activity against both Gram-positive and -negative bacteria as well as haemolytic activity on chicken, human and sheep erythrocytes. — ChEBI

Machine-generated and unreviewed. Identity, structure and cross-references come straight from ChEBI's and CARD's own data; no curator has signed off on this record yet.

Classification

Strictly broader compounds or drug classes this molecule belongs to.

CHEBI:15722 CHEBI:15722
CHEBI:78506 CHEBI:78506

Chemical structure

Computed structure properties
Molecular formula	C78H138N20O16
Charge	0
Average mass	1612.086 Da
Monoisotopic mass	1611.05997 Da
Source	ChEBI
InChIKey	NSFBOCKFBVQQKB-CQWNSWRRSA-N

SMILES

CC[C@H](C)[C@H](NC(=O)[C@H](CO)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCCCN)NC(=O)[C@@H](N)CC(C)C)C(=O)N[C@H](C(=O)N[C@@H](CO)C(=O)N[C@@H](Cc1cnc2ccccc12)C(=O)N[C@@H](C)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCCN)C(=O)N[C@H](C(=O)N[C@@H](CC(C)C)C(N)=O)C(C)C)C(C)C

InChI

InChI=1S/C78H138N20O16/c1-14-47(12)64(98-75(111)61(41-100)94-70(106)55(29-19-23-33-81)90-73(109)58(37-44(6)7)92-69(105)54(28-18-22-32-80)88-67(103)51(83)35-42(2)3)78(114)97-63(46(10)11)77(113)95-60(40-99)74(110)93-59(38-49-39-85-52-26-16-15-25-50(49)52)72(108)86-48(13)66(102)87-53(27-17-21-31-79)68(104)89-56(30-20-24-34-82)71(107)96-62(45(8)9)76(112)91-57(65(84)101)36-43(4)5/h15-16,25-26,39,42-48,51,53-64,85,99-100H,14,17-24,27-38,40-41,79-83H2,1-13H3,(H2,84,101)(H,86,108)(H,87,102)(H,88,103)(H,89,104)(H,90,109)(H,91,112)(H,92,105)(H,93,110)(H,94,106)(H,95,113)(H,96,107)(H,97,114)(H,98,111)/t47-,48-,51-,53-,54-,55-,56-,57-,58-,59-,60-,61-,62-,63-,64-/m0/s1

Also called

L-leucyl-L-lysyl-L-leucyl-L-lysyl-L-seryl-L-isoleucyl-L-valyl-L-seryl-L-tryptophyl-L-alanyl-L-lysyl-L-lysyl-L-valyl-L-leucinamide (EXACT_SYNONYM)— chebi
Leu-Lys-Leu-Lys-Ser-Ile-Val-Ser-Trp-Ala-Lys-Lys-Val-Leu-NH2 (EXACT_SYNONYM)— chebi
MP-B (EXACT_SYNONYM)— chebi
Mast cell degranulating peptide (Vespa basalis) (EXACT_SYNONYM)— chebi

Cross-references

Equivalent identifiers for this same structure in other resources.

cas:137354-65-5

Activity roles

Every antimicrobial role a source asserts for this compound — the unreduced evidence behind its antimicrobial_class.

CHEBI:33282 CHEBI:33282

Source concepts

Every upstream concept that resolved to this record. The merge is the product: this is what shows ChEBI and CARD are describing the same structure.

Upstream concepts merged into this record
Source	Native ID	Label	Minted CURIE	Version
CHEBI	`CHEBI:78511`	mastoparan-B	`antibioticmech:chebi-96bbb3d626`	2026-08-30

Curation history

SEEDED_FROM_SOURCES 2026-08-30 · seed_from_sources
Seeded from data/raw/ inventories (CHEBI)
RESEEDED_FROM_SOURCES 2026-08-30 · seed_from_sources
Re-seeded from updated data/raw/ inventories
RESEEDED_FROM_SOURCES 2026-08-30 · seed_from_sources
Re-seeded from updated data/raw/ inventories

Provenance

Seeded by scripts/seed_from_sources.py from the committed inventories in data/raw/. View the record.