Polyphosphates in the red macroalga Chondrus crispus (Rhodophyceae)

Abstract

SUMMARYPlants of Chondrus crispus Stackhouse, collected from mid-littoral tidepools, were treated as follows. Some plants were kept for a few weeks under controlled starvation conditions in order to decrease their initial content of total tissue phosphorus, then incubated for up to 48 h in phosphorus (15 /^M) and nitrogen (25 /iM)enriched sea water. Other plants were directly incubated in enriched sea water. Chemical analyses showed that the total phosphorus content of fresh and starved plants remained stable, reflecting the nutritional status of the plants. The predominant acid-soluble phosphate fraction was larger in fresh than in starved plants. The content of acid-soluble polyphosphates, similar in both types of plants at the beginning of the experiment, doubled in starved plants, and increased by a factor of 2-7 in fresh plants, over 48 h. The content of acid-insoluble polyphosphates was lower than that of acid-soluble polyphosphates.Transmission electron microscopy and energy dispersive X-ray microanalysis confirmed the presence, mostly in medullary cells, of acid-insoluble polyphosphates in the form of cytoplasmic granules and precipitates along the plasmalemma, particularly near pit plugs. This is the first report of such phosphorus storage structures in a red macroalgal species.

Uptake kinetics and storage capacity of dissolved inorganic phosphorus and corresponding N:P dynamics in Ulva lactuca (Chlorophyta)

“…Over‐compensation of internally stored phosphorus can occur when phosphorus‐starved algae are re‐introduced to high concentrations of external DIP (Aitchison and Butt , Chopin et al. ). Finally, oscillating uptake can also reflect a stress reaction to high external nutrient concentration (e.g., Fourcroy , Jiang and Yu‐Feng ), allowing for mobilization and uptake of sufficient DIP to provide temporary relief.…”

Phylogeography of the Northern Atlantic species Chondrus crispus (Gigartinales, Rhodophyta) inferred from nuclear rDNA internal transcribed spacer sequences

“…Usually, C. crispus flourishes in the lower shore and is distributed mainly on Atlantic coasts of Europe, such as Germany (Franklin et al, 2001), France (Gall et al, 1990;Boyen et al, 1994;Donaldson et al, 2000), Spain (Gutierrez & Ferná ndez, 1992), the Netherlands (Groen et al, 1997), and Northern America like Canada (Chopin et al, 1996(Chopin et al, , 1997Donaldson et al, 1998) and USA (Carrington et al, 2001;Zertuche-Gonzá lez et al, 2001), as well as in the Northern Russia, Western Baltic and Iceland (Dixon & Irvine, 1977). These surveys indicate that C. crispus is a cold temperate species restricted to the Northern Atlantic, and its distribution may be correlated with seasonal global isotherms (van den Hoek, 1984).…”

Relationship between tissue phosphorus and seawater phosphate in the brown alga Hormosira banksii

“…Phosphorus is taken up by seaweeds from the surrounding seawater as phosphate directly or, if phosphate supply is limiting growth, indirectly via extracellular alkaline phosphatase activity that releases phosphate from organic sources of phosphorus. In seaweeds, phosphate may be stored as polyphosphate in the vacuole (Lundberg et al 1989), chloroplast (Rutter & Cobb 1983) or cytoplasm (Bock et al 1996;Chopin et al 1997;Chopin et al 2004). The amount of phosphorus present in the tissues of a seaweed can change depending on the relative rate of supply (phosphate uptake) and demand (growth and reproduction).…”