/■. H. JOHXSOX, E. H.-C. S/E, AM) )'. HANEDA 209 



he llu' case with Coiiyinihix (.SI), or to instability of either the hici- 

 lirin. siK h as tliat ol lim,<;i (I), or the hiciferase, such as that of 

 (c'l lain IncMics (,S7) . 



Luminescence of Dried Materials 



The fact, however, that a niimljer of instances have been found in 

 which the whole organism, or its photogenic organ or cells, can be 

 dried and can then linninesce again on moistening, shows that the 

 necessary reactants are not hopelessly unstable except in a living 

 environment. Examples of this phenomenon, among organisms which 

 thus far have not yielded active extracts of luciferin and luciferase, 

 include the following: jellyfish, sea pens, ctenophores (Beroe) , 

 nemerteans, polychaetes (Chaetopterus) , earthworms, nudibranchs, 

 cephalopods, copepods, myriapods, ophiurids, and tunicates (27) . 



Indirect evidence for an enzyme-substrate system, where these two 

 components have not been successfidly separated, can sometimes be 

 foiuid in the effects of factors w^hich influence enzyme action or states 

 of proteins in general. For example, if urethane is added during the 

 decay of luminescence in the slime secreted by Chaetopterus, the 

 intensity of the light drops at once, but if sea water is then added to 

 reduce the concentration of the drug, the intensity immediately in- 

 creases, thus indicating a reversible inhibition (33) . More re- 

 cently- it has been shown that desiccated photogenic tissue of jelly 

 fish (Aquorea) or sea pens {Leioptilus) can be ground to a powder 

 and taken up in concentrated solutions of urea, ammonium sulfate, 

 sodium chloride, etc., which partially suppress the light normally 

 emitted on moistening, but a bright flash of light will subsequently 

 occur on dilution with distilled ^vater (Fig. 1) . In 6 M urea, the 

 system gradually deteriorates at room temperature, and in 10 M 

 urea it undergoes rapid destruction. Similar results are obtained with 

 homogenates prepared by squeezing whole jellyfish, or excised ring 

 canals with their associated photogenic tissue, through several layers 

 of cheese cloth. On adding ammoniimi sulfate to 60 per cent satura- 

 tion, a precipitate forms which is highly active on dilution with 

 distilled water, and retains its activity for days. The ring canals can 

 be dehydrated with acetone at — 10°C, or colder, and on adding 

 water to the dry powder prejiared therefrom, a bright flash of light 

 occurs. No additional light could then be elicited by addition of 



-The work on Aquorea and Lci()j>lihis reported licre was carried out in the 

 summer of 19r)9 at the Marine Laboratory of the University of Washington. Friday 

 Harbor, \\'ashington. 



