Tenebrosin-A, a new cardiostimulant protein from the Australian sea anemone Actinia tenebrosa
Thomson, M.; Moritz, R.L.; Simpson, R.J.; Norton, R.S.
Biochemistry International 15(4): 711-718
1987
ISSN/ISBN: 0158-5231 PMID: 2893616 Document Number: 301598
A new cardiac stimulatory protein, tenebrosin-A, has been isolated from the Australian sea anemone Actinia tenebrosa by gel filtration and cation-exchange chromatography, followed by cation-exchange HPLC. Its purity is established by analytical reversed-phase HPLC and N-terminal sequence analysis. According to SDS-PAGE, its apparent Mr is 20,000 daltons. Amino acid analysis indicates that it contains 186 residues, and is devoid of cysteine or cystine. Tenebrosin-A exerts a strong positive inotropic effect on isolated guinea pig atria at a concentration of 1.4 nM, with little chronotropic activity.