The journal Chemistryworld selected some 20 examples of “Cutting edge chemistry in 2015” from around the world. It brings together articles like ”On the origin and variation of colors in lobster carapace”, authored by a group including LiU researchers Bo Durbeej and Olle Falklöf, with work on an ebola vaccine and Pluto’s atmosphere.
From blue to red“The great thing about our model is that it can be understood by a senior high school student,” says Bo Durbeej, senior lecturer at Linköping University’s Department of Physics, Chemistry and Biology.
OK, here’s the explanation:
Living lobsters are dark blue in colour because their shells contain the protein crustacyanin. This binds a chromophore called astaxanthin, which – confusingly – has a distinctly red-orange colour. For instance it gives salmon its colour. So using this logic, living lobsters should be red – if something strange isn’t going on.
90 year old mystery
The astaxanthin in the living lobster’s shell is dark blue because it occurs in an unexpected, negatively charged form, which absorbs light of another wavelength. This form is stabilised by the surrounding protein, crustacyanin. But when the lobster is lowered into the boiling water, this protein is destroyed, the astaxanthin returns to its original form and the colour changes from dark blue to orange-red.
Cutting edge chemistry in 2015
On the origin and variation of colors in lobster carapace av S. Begum et al. Physical Chemistry Chemical Physics No 26, 2015