An autoradiographic examination of carbon fixation, transfer and utilization in the Riftia pachyptila symbiosis

Bright, Monika; Keckeis, Hubert; Fisher, Charles R.

doi:10.1007/s002270050722

Cited by 81 publications

(82 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The distinction of different symbiotic morphotypes of the same phylotype is based not only on size and shape modulations and on different locations within the trophosome lobules, but also on different physiological abilities. This has been proven for inorganic carbon fixation and incorporation rates (Bright et al 2000), but is also evidenced by the increase in the amount of glycogen storage from the central rods to the large peripheral cocci.…”

Section: Discussionmentioning

confidence: 73%

“…Glycogen distribution is not correlated with incorporation rates of organic carbon, which were similarly high in the central rods and the large peripheral cocci after the 1 to This organic carbon incorporation shows that there is no gradient in the compounds used in chemosynthesis (Bright et al 2000). Even if there were some limitation to the formation of a nitrogen or phosphorus gradient (chemicals that, in free-living bacteria, are known to result in glycogen synthesis when organic carbon is available in excess; Preiss 1984, Preiss & Romeo 1989, Lou et al 1997, any such limitation would result in high glycogen concentrations in the center where the pool would be depleted most and low concentrations at the periphery.…”

Section: Discussionmentioning

confidence: 91%

“…Its enormous tube length (up to 1.5 m; Jones 1981) and high growth rate (Lutz et al 1994) depend on a successful nutritional symbiosis with endosymbiotic, chemolithoautotrophic, sulfide-oxidizing bacteria (Fisher & Childress 1986, Felbeck & Jarchow 1998, Bright et al 2000. The symbionts are harbored in the trophosome, a specialized organ in the trunk of R. pachyptila that is differentiated into lobules.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Glycogen storage in the Riftia pachyptila trophosome: contribution of host and symbionts

Sorgo¹,

Gaill²,

Lechaire³

et al. 2002

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Glycogen storage in host tissue and symbiotic bacteria in the anterior trophosome of the vestimentiferan tubeworm Riftia pachyptila Jones, 1981, was investigated using transmission electron microscope and stereological methods. The relative glycogen content (RGC) of each partner was calculated from the percentage of host and bacterial cytoplasm area taken up by glycogen and from the percentage area that host and symbionts occupy within a trophosome lobule section. Our results show that host and symbionts contribute equally to the total glycogen content of the trophosome; this ratio remains similar for up to 40 h of hypoxia. Furthermore, there is a glycogen gradient in the lobule. In both symbiotic partners, the glycogen content increased from the lobule center toward the periphery, implying different metabolic activities of host cells and bacteria depending on their location within a trophosome lobule.

show abstract

Section: Discussionmentioning

confidence: 73%

Section: Discussionmentioning

confidence: 91%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Glycogen storage in the Riftia pachyptila trophosome: contribution of host and symbionts

Sorgo¹,

Gaill²,

Lechaire³

et al. 2002

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

show abstract

“…Enzymes in the Trophosome-Analysis of the trophosome by electron microscopy has suggested the presence of the symbiont at various states of development as follows: dividing bacteria predominantly present in the central part of the trophosome lobules (clusters of bacteriocytes) and lysed bacteria present at the periphery (45). We hypothesized that such a specific tissue organization could exist across the entire trophosome, accompanied by differential distribution of the enzymes of catabolism FIG.…”

Section: Heterogeneity Of Localization Of Pyrimidine Metabolismmentioning

confidence: 99%

“…Ultrastructural cellular studies have shown the occurrence of symbiont lysis in the trophosome (45,58,59), and it was proposed that such lysis might represent a nutritional source for R. pachyptila. Our enzymatic analysis shows the existence of a gradual increase of the catabolic enzyme activities, 5Ј-nucleotidase and UPase, from the center toward the peripheral region of the trophosome.…”

Section: Figmentioning

confidence: 99%

Catabolism of Pyrimidine Nucleotides in the Deep-sea Tube WormRiftia pachyptila

Pastra-Landis

Gaill

Hervé³

2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

The present study describes the distribution and properties of enzymes of the catabolic pathway of pyrimidine nucleotides in Riftia pachyptila, a tubeworm living around deep-sea hydrothermal vents and known to be involved in a highly specialized symbiotic association with a bacterium. The catabolic enzymes, 5-nucleotidase, uridine phosphorylase, and uracil reductase, are present in all tissues of the worm, whereas none of these enzymatic activities were found in the symbiotic bacteria. The 5-nucleotidase activity was particularly high in the trophosome, the symbiont-harboring tissue. These results suggest that the production of nucleosides in the trophosome may represent an alternative source of carbon and nitrogen for R. pachyptila, because these nucleosides can be delivered to other parts of the worm. This process would complement the source of carbon and nitrogen from organic metabolites provided by the bacterial assimilatory pathways. The localization of the enzymes participating in catabolism, 5-nucleotidase and uridine phosphorylase, and of the enzymes involved in the biosynthesis of pyrimidine nucleotides, aspartate transcarbamylase and dihydroorotase, shows a non-homogeneous distribution of these enzymes in the trophosome. The catabolic enzymes 5-nucleotidase and uridine phosphorylase activities increase from the center of the trophosome to its periphery. In contrast, the anabolic enzymes aspartate transcarbamylase and dihydroorotase activities decrease from the center toward the periphery of the trophosome. We propose a general scheme of anatomical and physiological organization of the metabolic pathways of the pyrimidine nucleotides in R. pachyptila and its bacterial endosymbiont.

show abstract

The skin of Osedax (Siboglinidae, Annelida): An ultrastructural investigation of its epidermis

Katz

Klepal

Bright

2010

Journal of Morphology

View full text Add to dashboard Cite

The symbiotic polychaetes of the genus Osedax living on the bones of whale carcasses have become known as bone-eating worms. It is believed that whale bones are the source of nutrition for those gutless worms and that fatty acids are produced by their symbionts and transferred to the host. However, the symbionts are of the heterotrophic group Oceanospirillales and as such are not able to synthesize organic carbon de novo. Also, they are not housed in close contact to the bone material. We studied the ultrastructure of the integument overlying the symbiont housing trophosome in the ovisac region and the roots region and of the symbiont-free trunk region of Osedax to investigate the host's possible contribution in feeding for the whole symbiosis. The epidermis differs conspicuously between the three regions investigated and clearly points to being correlated with different functions carried out by those regions. The ultrastructure of the integument of the root region changed towards the ovisac region and corresponds with the change of the ultrastructure observed in the Osedax trophosome. We suggest that the epidermis in the root region is tightly linked to bone degradation and nutrient uptake. The trunk region possess two types of unicellular gland cells, at least one of which seems to be involved in secretion of the gelatinous tube of adult Osedax females.

show abstract

An autoradiographic examination of carbon fixation, transfer and utilization in the Riftia pachyptila symbiosis

Cited by 81 publications

References 20 publications

Glycogen storage in the Riftia pachyptila trophosome: contribution of host and symbionts

Glycogen storage in the Riftia pachyptila trophosome: contribution of host and symbionts

Catabolism of Pyrimidine Nucleotides in the Deep-sea Tube WormRiftia pachyptila

The skin of Osedax (Siboglinidae, Annelida): An ultrastructural investigation of its epidermis

Contact Info

Product

Resources

About