The roles of oxygen and ammonia in the symbiotic relationship between the spotted salamander Ambystoma maculatum and the green alga Oophila amblystomatis during embryonic development

  title={The roles of oxygen and ammonia in the symbiotic relationship between the spotted salamander Ambystoma maculatum and the green alga Oophila amblystomatis during embryonic development},
  author={Daniel P Small and Richard S. Bennett and Cory D. Bishop},
Some of the positive benefits of the symbiotic relationship between the yellow spotted salamander Ambystoma maculatum and the green alga Oophila amblystomatis on salamander embryonic development have been well documented. However, the fundamental basis of the relationship, in terms of the exchange of metabolic and photosynthetic products, is under debate, especially as it relates to newly discovered endosymbiotic aspects of the relationship. We developed a novel experimental approach in which… 

Heterotrophic Carbon Fixation in a Salamander-Alga Symbiosis

The results confirm earlier studies suggesting a role of heterotrophic carbon fixation during vertebrate embryonic development and show that the considerable capacity of developing A. maculatum embryos for inorganic carbon fixation precludes the ability to distinguish any minor role of photosynthetically transferred carbon from algal symbionts to host salamanders using bicarbonate introduced to the egg system as a marker.

Physiological benefits and latent effects of an algal-salamander symbiosis.

  • Daniel P SmallC. Bishop
  • Biology
    Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
  • 2020

Transcriptome analysis illuminates the nature of the intracellular interaction in a vertebrate-algal symbiosis

Transcriptional changes in salamander cells suggest an innate immune response to the alga, with potential attenuation of NF-κB, and metabolic alterations indicative of modulation of insulin sensitivity.

Patterns of bacterial diversity in embryonic capsules of the spotted salamander Ambystoma maculatum: an expanding view of a symbiosis.

There are bacterial taxa whose presence is held in common spatially and temporally among capsules and that the symbiosis between O. amblystomatis and A. maculatum may involve these taxa.

Co-cultures of Oophila amblystomatis between Ambystoma maculatum and Ambystoma gracile hosts show host-symbiont fidelity

Data reveal a potential host-symbiont fidelity that allows the unique endosymbiosis to occur in A. maculatum and A. gracile hosts, and suggests the intracapsular algae are assimilating ammonia for nitrogen metabolism and may be undergoing a life-cycle transition.

The establishment of endosymbiosis: An experimental and computational investigation using the artificial symbiont Synechocystis

This project applies metabolic modelling, using flux balance analysis (FBA), to this evolutionary transition to study the metabolic adaptations necessary for the symbiont to transition from free-living to endosymbiotic, and shows the applicability of FBA modelling to those ancient evolutionary transitions that were driven by metabolic exchanges, like endosYmbioses.

Metabolic constraints for a novel symbiosis

The results show the applicability of FBA modelling to ancient evolutionary transitions driven by metabolic exchanges, and predict how newly established endosymbioses, governed by conflict, will differ from a well-developed one that has reached a mutual-benefit state.

Egg mass polymorphism in Ambystoma maculatum is not associated with larval performance or survival, or with cell density of the algal symbiont Oophila amblystomatis

The data do not support the hypothesis that variation in predator density and light availability among microhabitats could maintain the two phenotypes within populations.

Diversity and substrate-specificity of green algae and other micro-eukaryotes colonizing amphibian clutches in Germany, revealed by DNA metabarcoding

A multi-marker DNA metabarcoding study to characterize the community of algae and other micro-eukaryotes associated with agile frog (Rana dalmatina) clutches and confirmed in samples the existence of two distinct clades of green algae assigned to Oophila in past studies.

Evolution of Photosynthetic Eukaryotes; Current Opinion, Perplexity, and a New Perspective.

It is proposed that the free-living ancestors to the plastids may have originated from a diversified lineage of cyanobacteria that were prone to symbioses, akin to some modern-day algae such as the Symbiodiniaceae dinoflagellates and Chlorella-related algae that associate with a number of unrelated host eukaryotes.



Acid Water Interferes with Salamander–Green Algae Symbiosis during Early Embryonic Development

It is concluded that chronic exposure to acidic breeding ponds had a profound effect on the microenvironment of developing A. maculatum embryos, which resulted in an elevation of potentially harmful metabolic end products and inhibited growth.

Symbioses between salamander embryos and green algae

Earlier research on this symbiosis between Ambystoma maculatum embryos and green algae is summarized and gaps in understanding are emphasized and various research avenues are suggested to address these unanswered questions.

Intracellular invasion of green algae in a salamander host

The invasion of algae into salamander host tissues and cells represents a unique association between a vertebrate and a eukaryotic alga, with implications for research into cell–cell recognition, possible exchange of metabolites or DNA, and potential congruence between host and symbiont population structures.

Embryonic motility and hatching success of Ambystoma maculatum are influenced by a symbiotic alga

Embryonic motion is potentially vital to salamander development and muscular contractions were more frequent in embryos from algae-inhabited egg masses in light than those in the dark; thus embryos with less O2 reduced muscular activity, thereby reducing energy consumption when O2 availability was compromised.

Intermittent hypoxia in eggs of Ambystoma maculatum: embryonic development and egg capsule conductance

Intermittent hypoxia caused comparable but less pronounced developmental delays than chronic Hypoxia and failed to elicit the measurable change in GO2 seen in ambystomatid salamander eggs exposed to chronic hypoxIA.

Observations on the Eggs of Ambystoma Maculatum with Especial Reference to the Green Algae Found Within the Egg Envelopes

Algae probably "helps provide oxygen for the developing embryos in the presence of light and robs them of it in darkness" as well as on the possibility of a symbiotic relationship.

Metabolic interactions between algal symbionts and invertebrate hosts.

The loss of the algal symbiont and its metabolic contribution to the host has the potential to result in the transition from a coral-dominated to an algal-dominated ecosystem.

Intracapsular algae provide fixed carbon to developing embryos of the salamander Ambystoma maculatum

It is shown that carbon fixed by O. amblystomatis is transferred to the embryos, providing the first evidence of direct translocation of photosynthate from a symbiont to a vertebrate host and showing that larger algal populations promote faster embryonic growth and development.

Symbiosis between salamander eggs and green algae: microelectrode measurements inside eggs demonstrate effect of photosynthesis on oxygen concentration

Photosynthetic oxygen production by the chlamydomonads exceeded respiratory consumption by the embryo–algae complex and led to oxygen supersaturation inside eggs, even when water surrounding the egg mass was almost anoxic.

Phylogenetic Analysis of Algal Symbionts Associated with Four North American Amphibian Egg Masses

Combined analysis shows that symbiotic algae found in egg masses of four North American amphibians are closely related to each other, and form a well-supported clade that also contains three strains of free-living chlamydomonads.