FREE AMINO ACIDS IN INVERTEBRATES 165 
OCCURRENCE OF COMPOUNDS RELATED TO @-AMINO ACIDS IN INVERTEBRATES 
Many compounds of nitrogen have been isolated from invertebrates; in some instances 
an important role has been ascribed to them as in the case of arginine phosphate 
which replaces creatine phosphate in a number of invertebrates ; in other instances no 
role has been assigned to the various compounds discovered in invertebrates. This is 
the largest group and it appears that the more widely distributed the compound the 
less is known about its role. Such compounds as taurine for example are found in 
both vertebrates and invertebrates in high concentrations but no particular role has 
been assigned to it. A partial list of compounds of nitrogen isolated from invertebrates 
follows: 
Taurine 
Taurine was isolated from extracts of the clam Mytilus edulis by KELLY**. M. edulis 
contains very large quantities of taurine: as much as 4% of its fresh weight. HENZE*8 
H,N—CH,—CH,—SO,H 
found it in the octopus; KossEL AND EDLBACHER*™ found it in some echinoderms; 
DABIE, Vi 
TAURINE CONTENT IN VARIOUS MOLLUSCS 



Mollusca Environment Taurine 
Gastropoda 
Lymnaea palustris Fresh water = 
Marisa cornuarietis Fresh water — 
Pomacea bridgest Fresh water — 
Rumina decollata Terrestrial — 
Otala lactea Terrestrial — 
Mesodon thyroidus Terrestrial = 
Bulimulus alternatus Terrestrial — 
Murex fluvescens Marine ae 
Littovina ivvorata Marine + 
Oliva sayana Marine + 
Polinices duplicata Marine a 
Busycon perversum Marine + 
Siphonaria lineolata Marine Ar 
Fasciolaria distans Marine ae 
Thais haemastoma haysae Marine =F 
Pelecypoda 
Anadonta grandis Fresh water = 
Quadrula quadrula Fresh water = 
Lampsilis sp. Fresh water = 
Elliptio sp. Fresh water — 
Rangia cuneata Brackish-fresh water a 
Byrachiodontes vecurvus Brackish-marine = 
Crassostrea virginica Brackish-marine ot 
Donax variabilis Marine + 
Venus mercenaria Marine 
Dosinia discus Marine ae 
Ayca incongrua Marine + 
Arca compechiensis Marine + 
Noetia ponderosa Marine 35 
Cephalopoda 
Loliguncula brevis Marine - 


References p. 174/175 
