cDNA Sequences for Four Snake Venom Metalloproteinases: Structure, Classification, and Their Relationship to Mammalian Reproductive Proteins

摘要: Presented here are four new cDNA sequences for hemorrhagic metalloproteinases from Crotalus atrox venom, toxins a, b, c, and d. Comparison of the translated open reading frames to mature protein gives evidence post-translational processing at both amino carboxyl termini. This comparison is also basis a classification system these precursors, based on their different sizes. Protein in zymogen region support hypothesis cysteine-switch type mechanism maintaining latency. The coordination geometry around active site zinc ion discussed. relationship between venom family mammalian reproductive proteins supported by sequences. cysteine pattern carboxyl-terminal domain largest proteinase, toxin compared other proteinases proteins, showing striking similarities subtle differences. It would appear that have resulted deletions subsequent divergence larger ancestor, one they may shared with aforementioned proteins.