Haemoglobins, key molecules for life at deep-sea hydrothermal vent sites
Toulmond, A.; Lallier, F.; Zal, F.; Hourdez, S. (1997). Haemoglobins, key molecules for life at deep-sea hydrothermal vent sites, in: Biologie des sources hydrothermales profondes = Biology of deep-sea hydrothermal vents: Journées d'échanges du Programme DORSALES = DORSALES Workshop Roscoff 6-8 octobre 1997. Cahiers de Biologie Marine, 38(2): pp. 144 In: (1997). Biologie des sources hydrothermales profondes = Biology of deep-sea hydrothermal vents: Journées d'échanges du Programme DORSALES = DORSALES Workshop Roscoff 6-8 octobre 1997. Cahiers de Biologie Marine, 38(2)[s.n.][s.l.]. 111-149 pp., more In: Cahiers de Biologie Marine. Station Biologique de Roscoff: Paris. ISSN 0007-9723; e-ISSN 2262-3094, more |  |
| Authors | | Top | - Toulmond, A., more
- Lallier, F.
- Zal, F.
- Hourdez, S.
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| Abstract | Twenty years ago, before the discovery of the deep-sea hydrothermal vents and their specific fauna, animal haemoglobins were considered essentially for their ability to bind and transport molecular oxygen from the external medium to the tissues and, consequently, for the central function they have in the respiratory physiology of vertebrates and invertebrates. Changes in this view have occurred in three steps:(i) firstly, in 1983, when Arp et al. showed that the blood of the hydrothermal vent tubeworm Riftia pachyptila was able to reversibly bind hydrogen sulphide; (ii) secondly, in 1987, when Arp et al. demonstrated that the extracellular haemoglobins contained in the blood of Riftia were the sulphide-binding proteins; (iii) thirdly, recently, when Zal and collaborators revealed that S-sulphaemoglobin and persulphide-groups processes were the mechanisms accountable for sulphide-binding mechanisms (Zal et al. 1997a, Zal et al. submitted), involving either free cystein residues or disulphide bridges respectively. Moreover, cystein residues are also present in the haemoglobins of at least two species of polychaetes living in sulphide-rich environments, i.e. the intertidal lugworm Arenicola marina (Zal et al. 1997b) and the hydrothermal pompei worm Alvinella pompejana (Zal et al. 1997c). These cysteins, in binding sulphide, could participate in its detoxification. In this context, we must reconsider previous ideas on the origin and evolution of the functional properties of haemoglobins, especially their implication in a coupled detoxification-transport process of both oxygen and sulphide. Incidentally, these findings support the idea of a narrow relationship between annelids and vestimentiferans. |
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