Protein variation in the venom spat by the red spitting cobra, Naja pallida (Reptilia : Serpentes)

The venom spat by red spitting cobras (Naja pallida) was analyzed to docume nt variations in protein composition occurring over short temporal periods (less than 5 min). These cobras exhibited distinct control of venom flow wi th spits averaging 1.7% of the volume of the venom gland, thus enabling the cobras to rapidly expel over 40 consecutive spits. Variations in the low a nd high molecular weight proteins were observed when comparing the Ist, 20t h and 40th spits produced by the same specimens. The first few spits were c haracterized by a distinctive 9 kDa protein which was never observed beyond the 7th spit, was present in milked venom and was present when the spittin g behavior was preceded by a 5 min period of induced defensive behaviors. ( C) 1999 Elsevier Science Ltd. All rights reserved.