1.C.32 The Amphipathic Peptide Mastoparan (Mastoparan) Family

Mastoparans are 14 (sometimes 13 or 15) amino acyl residue, amphipathic, α-helical peptides present in the venom of hornets, wasps and yellow jackets. They exert numerous biological effects including (1) degranulation of mast cells, (2) G-protein receptor mimicry, (3) phospholipase A2 stimulation, and (4) inhibition of Golgi vesicle transport. They all increase bilayer permeability to hydrophilic solutes by forming short lived pores. Because they are too short to span the membrane as amphipathic α-helices (a configuration they assume when in association with membranes), it is thought that they form bundles of peptides in a so called 'barrel-stove' configuration. Pore formation has been demonstrated electrophysiologically as well as by demonstrating increased permeability to hydrophilic molecules and dyes. They also exhibit cytotoxicity, but certain amino acid substitutions reduce the activity (Irazazabal et al. 2016). Their actual transmembrane architecture is unknown.

The generalized transport reaction catalyzed by mastoparan pores is:

Small molecules (in) Small molecules (out)



This family belongs to the Cecropin Superfamily.

 

References:

Arbuzova, A and G. Schwarz (1999). Pore-forming action of mastoparan peptides on liposomes: a quantitative analysis. Biochim. Biophys. Acta. 1420: 139-152.

Arcisio-Miranda, M., M.P. Dos Santos Cabrera, K. Konno, M. Rangel, and J. Procopio. (2008). Effects of the cationic antimicrobial peptide eumenitin from the venom of solitary wasp Eumenes rubronotatus in planar lipid bilayers: Surface charge and pore formation activity. Toxicon. 51: 736-745.

Irazazabal, L.N., W.F. Porto, S.M. Ribeiro, S. Casale, V. Humblot, A. Ladram, and O.L. Franco. (2016). Selective amino acid substitution reduces cytotoxicity of the antimicrobial peptide mastoparan. Biochim. Biophys. Acta. 1858: 2699-2708.

Examples:

TC#NameOrganismal TypeExample
1.C.32.1.1

Mastoparan (INWKKMAATALKMI).  Amiino acid substitutions gave rise to mastoparans that displayed a broad-spectrum antimicrobial activity against bacteria and fungi (MIC in the range 3-25μM), without being hemolytic or cytotoxic (Irazazabal et al. 2016).

Wasps, hornets, yellowjackets

Mastoparan of Parapolybia indica

 
1.C.32.1.2Mastoparan X (INWKGIAAMAKKLL) Hornets Mastoparan X of Vespa xanthoptera
 
1.C.32.1.3Mast cell degranulation peptide, Mastoparan (INLKAIAALVKKVL) Wasps Mastoparan of Vespa orientalis
 
1.C.32.1.4Mastoparan M (INLKAIAALAKKLL) Wasps Mastoparan M of Vespa mandarinia
 
1.C.32.1.5

Mastoparan C (LNLKALLAVAKKIL)

Wasps

Mastoparan C of Vespa crabro

 
1.C.32.1.6Mastoparan (INLKALAALAKKIL) Yellowjackets Mastoparan of Vespula lewisii
 
1.C.32.1.7Mastoparan B (LKLKSIVSWAKKVL) Wasps Mastoparan B of Vespa basalis
 
Examples:

TC#NameOrganismal TypeExample
1.C.32.2.1

Polistes Mastoparan (VDWKKIGQHILSVL)

Wasps

Polistes Mastoparan of Polistes jadwigae

 
1.C.32.2.2

Eumenitin (LNLKGIFKKVASLLT) (K+ > Cl- selectivity) (Arcisio-Miranda et al., 2008).

Wasps

Eumenitin of Eumenes rubronotatus (P0C931)

 
Examples:

TC#NameOrganismal TypeExample
1.C.32.3.1Cabrolin (FLPLILRKIVTAL) Wasps Cabrolin of Vespa crabro