8G4B

Crystal structure of heterodimeric Crotoxin B from Crotalus durissus collilineatus

Summary for 8G4B

• Entry DOI: 10.2210/pdb8g4b/pdb
• Descriptor: Phospholipase A2 crotoxin basic subunit CBb, Phospholipase A2 crotoxin basic subunit CBd, SULFATE ION, ... (4 entities in total)
• Functional Keywords: phospholipase a2, neurotoxin, crotoxin b, hydrolase
• Biological source: Crotalus durissus collilineatus; More
• Total number of polymer chains: 2
• Total formula weight: 28474.28

Authors

Salvador, G.H.M.,Borges, R.J.,Fontes, M.R.M. (deposition date: 2023-02-09, release date: 2026-01-28)

Primary citation

Salvador, G.H.M.,Fernandes, C.A.H.,Borges, R.J.,Soares, A.M.,Fontes, M.R.M.
Structural studies with crotoxin B from Crotalus durissus collilineatus venom suggest a heterodimeric assembly formed by two new isoforms.
Biochimie, 218:46-56, 2024

PubMed Abstract: In accidents involving Crotalus snakes, the crotoxin complex (CTX) plays lethal action due to its neurotoxic activity. On the other hand, CTX have potential biotechnological application due to its anti-tumoral, anti-inflammatory, antimicrobial, analgesic and immunomodulatory properties. CTX is a heterodimer composed of Crotoxin A (CA or crotapotin), the acidic nontoxic and non-enzymatic component and; Crotoxin B (CB), a basic, toxic and catalytic PLA. Currently, there are two classes of CTX isoforms, whose differences in their biological activities have been attributed to features presented in CB isoforms. Here, we present the crystal structure of CB isolated from the Crotalus durissus collilineatus venom. It amino acid sequence was assigned using the SEQUENCE SLIDER software, which revealed that the crystal structure is a heterodimer composed of two new CB isoforms (colCB-A and colCB-B). Bioinformatic and biophysical analyses showed that the toxin forms a tetrameric assembly in solution similar to CB from Crotalus durissus terrificus venom, despite some differences observed at the dimeric interface. By the previously proposed classification, the colCB-B presents features of the class I isoforms while colCB-A cannot be classified into classes I and II based on its amino acid sequence. Due to similar features observed for other CB isoforms found in the NCBI database and the results obtained for colCB-A, we suggest that there are more than two classes of CTX and CB isoforms in crotalic venoms.

PubMed: 37659716
DOI: 10.1016/j.biochi.2023.08.018

Experimental method

X-RAY DIFFRACTION (1.89 Å)