TAURINE IN MARINE INVERTEBRATES
22 1
taurine is thought to involve oxidation and deamination of cysteine to
cystaldimine followed by the degradation of the latter to thiocysteamine
which spontaneously breaks down to cysteamine and sulphur. Cysteamine on oxidation is then converted to hypotaurine, some of which is
transsulphurated to thiotaurine (Jacobsen and Smith, 1968). Cysteamine
is also thought to be derived from cysteine via coenzyme A (Fig. 1).
TABLE VIII. ESTIMATED CONCENTRATIONS OF SIX AMINO ACIDS IN TISSUES OF
MARINE INVERTEBRATES
Figures estimated from histograms givon by Simpson et al. (1959).
p &l aminolg tiasue
Taurine
Aapartamic
tic
Species
Alanine Argi- Glycine
nine
Bunodoaoma covernata
Penaeua aztecw,
Clibanariua vittatw,
Siphonaria lineolata
Fmciolaria dietuna
Bu.ycon peruersurn
Thak haemaatoma
Polynices duplicata
Oliva aagana
Lithophaga biaulcda
Craaaoatrea virginica
Arm umbonata
Volsella demiaaua
Loliguncula brevie
Thyone sp.
Luidia elathrata
Pagurw, pollimris
1.0
1.0
3.0
1.0
0.8
10.0
5-2
6.5
56.0
2.0
0.8
23.0
4-0
4.0
6.0
2.8
0.5
2-4
7.0
4.5
23-0
2.4
0.3
36.0
5.5
1.4
2.4
3.0
1.2
4.3
2.0
2.0
5.0
2.3
1.5
12.0
4.0
3.0
2.5
1.2
2.0
15.0
7-4
4.5
20.0
1.0
3.0
16.0
18.0
3.0
8-0
1.5
2.3
60.0
2-3
1.0
1.0
1.5
0.5
5.6
1.4
11.0
0.8
1.0
14.0
-
7-0
1.0
6.3
5.5
1.5
6.0
5.0
1.5
6.0
6.0
2.5
70.0
12.0
1.0
11.5
2.2
1.2
10.0
15-0
1-4
20.0
2.0
0.6
55.0
14.0
2.0
20.0
-
0.5
-
5-0
0.4
34.0
2.5
2-6
11.0
The work of Yoneda (1 967) on Mytitus adductor muscle-known to
contain large quantities of taurine (page 215) indicated that this pathway might also exist in invertebrates. He incubated cysteine and
cysteamine with enzyme extracts of adductor muscle and showed that
cysteamine was metabolized to a greater extent than cysteine, but at
this stage did not identify the products. Further studies (Yoneda, 1968)
showed that during the incubation of cysteamine with Mytilus adductor
muscle extract small amounts of hypotauriiie were formed, although
30% of the cysteamine was converted to taurine within two hours.
When hypotaurine was incubated with the same mixture an increase in
taurine was recorded. Yoneda (1968) concluded that there must be a
22 1
taurine is thought to involve oxidation and deamination of cysteine to
cystaldimine followed by the degradation of the latter to thiocysteamine
which spontaneously breaks down to cysteamine and sulphur. Cysteamine on oxidation is then converted to hypotaurine, some of which is
transsulphurated to thiotaurine (Jacobsen and Smith, 1968). Cysteamine
is also thought to be derived from cysteine via coenzyme A (Fig. 1).
TABLE VIII. ESTIMATED CONCENTRATIONS OF SIX AMINO ACIDS IN TISSUES OF
MARINE INVERTEBRATES
Figures estimated from histograms givon by Simpson et al. (1959).
p &l aminolg tiasue
Taurine
Aapartamic
tic
Species
Alanine Argi- Glycine
nine
Bunodoaoma covernata
Penaeua aztecw,
Clibanariua vittatw,
Siphonaria lineolata
Fmciolaria dietuna
Bu.ycon peruersurn
Thak haemaatoma
Polynices duplicata
Oliva aagana
Lithophaga biaulcda
Craaaoatrea virginica
Arm umbonata
Volsella demiaaua
Loliguncula brevie
Thyone sp.
Luidia elathrata
Pagurw, pollimris
1.0
1.0
3.0
1.0
0.8
10.0
5-2
6.5
56.0
2.0
0.8
23.0
4-0
4.0
6.0
2.8
0.5
2-4
7.0
4.5
23-0
2.4
0.3
36.0
5.5
1.4
2.4
3.0
1.2
4.3
2.0
2.0
5.0
2.3
1.5
12.0
4.0
3.0
2.5
1.2
2.0
15.0
7-4
4.5
20.0
1.0
3.0
16.0
18.0
3.0
8-0
1.5
2.3
60.0
2-3
1.0
1.0
1.5
0.5
5.6
1.4
11.0
0.8
1.0
14.0
-
7-0
1.0
6.3
5.5
1.5
6.0
5.0
1.5
6.0
6.0
2.5
70.0
12.0
1.0
11.5
2.2
1.2
10.0
15-0
1-4
20.0
2.0
0.6
55.0
14.0
2.0
20.0
-
0.5
-
5-0
0.4
34.0
2.5
2-6
11.0
The work of Yoneda (1 967) on Mytitus adductor muscle-known to
contain large quantities of taurine (page 215) indicated that this pathway might also exist in invertebrates. He incubated cysteine and
cysteamine with enzyme extracts of adductor muscle and showed that
cysteamine was metabolized to a greater extent than cysteine, but at
this stage did not identify the products. Further studies (Yoneda, 1968)
showed that during the incubation of cysteamine with Mytilus adductor
muscle extract small amounts of hypotauriiie were formed, although
30% of the cysteamine was converted to taurine within two hours.
When hypotaurine was incubated with the same mixture an increase in
taurine was recorded. Yoneda (1968) concluded that there must be a