Cell Surface Polysaccharides of the Red Alga Porphyridium

N-Glycosylation of the 66-kDa Cell-Wall Glycoprotein of a Red Microalga

“…That was not the case here, where no difference in the cell-wall glycoprotein amount was observed between these two growth phases. 13.01 Control ** Each peak matches its GU value in line with those shown in the NP-HPLC (in Figure 3). The molar rate was calculated by Water Empower software.…”

“…When red microalgae are grown in a liquid medium, the viscosity of the medium increases continuously as the polysaccharides are released from the cell surface [1,13]. As a result, during the logarithmic phase of growth polysaccharide capsules are thinnest, while during the stationary phase they are thickest.…”

“…[12,58,80] and of other red microalgae species [77,81] were found to be involved in the synthesis of the cell-wall polysaccharide. Polysaccharide synthesis in P. aerugineum and Rhodella reticulata and their subsequent packaging into vesicles takes place in the Golgi [77,82]. The vesicles are transported, fuse with the plasma membrane, and then secrete their contents on the cell surface [12,58,77].…”

Precursor-Product Relationships during Sulfate Incorporation into Porphyridium Capsular Polysaccharide

“…The sulfur has been shown to be present as the sulfate ester, the sulfate accounting for up to 7.6% of the polysaccharide by weight (1,2). Hydrolysis in trifluoroacetic acid yields primarily glucose, galactose, xylose, and several minor components including hexuronic acids (3). The polysaccharide is heterogeneous, acidic (due to free carboxyl and sulfate moieties), and is of a high mol wt.…”

“…In log phase, the rate of solubilization exceeds the rate of deposition, causing the capsule to decrease in dimension, whereas in sta-'This work was supported by the National Science Foundation Grant GB-18144. tionary phase, the rate of deposition exceeds the rate of solubilization, causing the capsule to increase in dimension (3). When cells were "pulsed" with SO4', labeled polysaccharide appeared in the medium, and the time-dependence of isotope incorporation showed a peak in the specific radioactivity of the excreted polysaccharide (2).…”