Characterization of a carotenoprotein from the carapace of the crab Macropipus puber.

An orange carotenoprotein (lambda max = 480 nm) containing astaxanthin as prosthetic group was extracted and purified from the carapace of the crab Macropipus puber. The extraction was made possible by means of Triton X-100, yielding an orange carotenoprotein, with a molecular weight of about 56,000. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated only a single polypeptide of 14,000 daltons, suggesting that the orange caroteno-protein was a tetrameric form.