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J. A. ALLEN AND M. R. GARRETT
of the thermodynamic potential is phosphocreatine > phosphoarginine > phosphotaurocyamine and phosphoglycocyamine.
Taurocyamine is not restricted t o polychaetes and sipunculids.
Thus, Robin and Roche (1954), investigating taurine and taurine
derivatives in various sponges and coelenterates, found it in Hymeniacedon caruncula Bowerbank, Thetia lyncurium Linn6 and in Actinia
equina Linn6. The same workers (Roche and Robin, 1954) had also
shown phosphoarginine and phosphocreatine to be present in
Hymeniacedon and Thetia respectively, but they did not find phosphotaurocyamine. The presence of taurocyamine and the absence of its
phosphagen clearly require further confirmation, but should this be so
then another function for taurocyamine must be found. A clue may lie
in experiments of Thoai et al. (1954, 1956) on the rat. The latter authors
found taurocyamine in the urine following the injection of taurine.
They did not find taurocyamine in muscle, but creatine is known to be
the guanidine derivative acting as N P acceptor. They suggest that aa
taurocyamine, like guanidine derivatives in general, is not easily hydrolysed by enzymes, it may be a link in a cycle in which amino acid can
be excreted, and ammonia eliminated in a non-toxic form (Fig. 1).
The presence of taurocyamine in the urine of rats (and also man) has
been confirmed by Schram and Crockaert (1957a and b). However,
they found no significant increase in excretion of taurocyamine when
taurine was injected into rats, nor was there any increase in the urine
of another supposed intermediate in this cycle, carbamyltaurine
(2-ureidoethanesulphonic acid), in the same experiments. However,
when carbamyltaurine and taurocyamine were injected, these were
quickly excreted, most within the following 24 hours. Curiously
carbamyltaurine (see Table I) was found nearly a century ago by
Salkowski (1872, 1873, 1876) in the urine of dogs following administration of taurine.
Before taurocyamine had been found in nature Ackermann (1936)
hypothesized that it should be an intermediate product between
taurine and its dimethyl derivative, asterubin (dimethyl guanidinotaurine). Ackermann (1935) had found asterubin in two species of
Asterias. Twenty years later, following the work of Thoai et al. (1953a
and b), Ackermann (1955) confirmed the presence of taurocyamine in
Areniwla, although he did not find asterubin, nor, surprisingly, taurine.
Jeuniaux et al. (1962a and b) showed that Asterias contains large
amounts of taurine, however, they suggest a role unconnected with that
of the formation of asterubin (see p. 236). This does not preclude the
possibility that Ackermann (1936) was correct and that because
taurine and asterubin are both present, taurocyamine may also be
J. A. ALLEN AND M. R. GARRETT
of the thermodynamic potential is phosphocreatine > phosphoarginine > phosphotaurocyamine and phosphoglycocyamine.
Taurocyamine is not restricted t o polychaetes and sipunculids.
Thus, Robin and Roche (1954), investigating taurine and taurine
derivatives in various sponges and coelenterates, found it in Hymeniacedon caruncula Bowerbank, Thetia lyncurium Linn6 and in Actinia
equina Linn6. The same workers (Roche and Robin, 1954) had also
shown phosphoarginine and phosphocreatine to be present in
Hymeniacedon and Thetia respectively, but they did not find phosphotaurocyamine. The presence of taurocyamine and the absence of its
phosphagen clearly require further confirmation, but should this be so
then another function for taurocyamine must be found. A clue may lie
in experiments of Thoai et al. (1954, 1956) on the rat. The latter authors
found taurocyamine in the urine following the injection of taurine.
They did not find taurocyamine in muscle, but creatine is known to be
the guanidine derivative acting as N P acceptor. They suggest that aa
taurocyamine, like guanidine derivatives in general, is not easily hydrolysed by enzymes, it may be a link in a cycle in which amino acid can
be excreted, and ammonia eliminated in a non-toxic form (Fig. 1).
The presence of taurocyamine in the urine of rats (and also man) has
been confirmed by Schram and Crockaert (1957a and b). However,
they found no significant increase in excretion of taurocyamine when
taurine was injected into rats, nor was there any increase in the urine
of another supposed intermediate in this cycle, carbamyltaurine
(2-ureidoethanesulphonic acid), in the same experiments. However,
when carbamyltaurine and taurocyamine were injected, these were
quickly excreted, most within the following 24 hours. Curiously
carbamyltaurine (see Table I) was found nearly a century ago by
Salkowski (1872, 1873, 1876) in the urine of dogs following administration of taurine.
Before taurocyamine had been found in nature Ackermann (1936)
hypothesized that it should be an intermediate product between
taurine and its dimethyl derivative, asterubin (dimethyl guanidinotaurine). Ackermann (1935) had found asterubin in two species of
Asterias. Twenty years later, following the work of Thoai et al. (1953a
and b), Ackermann (1955) confirmed the presence of taurocyamine in
Areniwla, although he did not find asterubin, nor, surprisingly, taurine.
Jeuniaux et al. (1962a and b) showed that Asterias contains large
amounts of taurine, however, they suggest a role unconnected with that
of the formation of asterubin (see p. 236). This does not preclude the
possibility that Ackermann (1936) was correct and that because
taurine and asterubin are both present, taurocyamine may also be