456 



Procecdings Columbia Biochemical Association [April 



scarch Lahoratory, Roosevelt Hospital, New York.) The hydro- 

 lytic action of castor bean lipase on ethyl butyrate was decreased in 

 aqueous Suspension and entirely inhibited by heating the aqueous 

 Suspension one to two hours in a water bath. Suspensions that had 

 been partially deactivated by Standing showed an increase in lipolytic 

 power when allowed to act in the presence of small amounts of 

 manganous sulfate ; those that had been completely deactivated by 

 heating showed a sHght but consistent activity in the presence of 

 manganous sulfate, and the activity was still greater if, to the water 

 Suspension of lipase, manganous sulfate was added and the Solution 

 allowed to stand fifteen to twenty hours before testing. 



These results suggest the tentative hypothesis that, in view of 

 the common function of manganese as an oxygen carrier, the lipase 

 in castor bean is formed from a zymogen, by oxidation aided by 

 an oxygen carrier, with or without simultaneous hydrolysis. 



67. The temperature limits of phosphorescence of luminous 

 bacteria. E. Newton Harvey. (Physiological Laboratory, 

 Princeton University, Princeton, N. /,) Light production by many 

 organisms has been observed at relatively high and low tempera- 

 tures, above or below which we should not expect biochemical 

 processes to continue. According to Panceri, Phyllirrhöe (a naked 

 snail of the Mediterranean) is luminous at 75° C, while Pyrosoma 

 (a pelagic ascidian) still glows at 60°. On the other band tissues 

 of the South American fire-fly, Pyrophorus, phosphoresce at 

 — 100° C. (Dubois) and Pseudomonas javanica (a protozoan) at 

 — 20° C. (Eijkmann). 



The following temperatures have been recorded for luminous 

 bacteria : 



The temperatures recorded are not excessively high or low, yet the 

 variations in the results suggest that further observations are 

 desirable. 



Luminous bacteria isolated from fish were grown on absorbent 



