Primary Cell Wall Composition of Bryophytes and Charophytes

Abstract

Major differences in primary cell wall (PCW) components between non-vascular plant taxa are reported. (1) Xyloglucan: driselase digestion yielded isoprimeverose (the diagnostic repeat unit of xyloglucan) from PCW-rich material of Anthoceros (a hornwort), mosses and both leafy and thalloid liverworts, as well as numerous vascular plants, showing xyloglucan to be a PCW component in all land plants tested. In contrast, charophycean green algae (Klebsormidium flaccidium, Coleochaete scutata and Chara corallina), thought to be closely related to land plants, did not contain xyloglucan. They did not yield isoprimeverose; additionally, charophyte material was not digestible with xyloglucan-specific endoglucanase or cellulase to give xyloglucan-derived oligosaccharides. (2) Uronic acids: acid hydrolysis of PCW-rich material from the charophytes, the hornwort, thalloid and leafy liverworts and a basal moss yielded higher concentrations of glucuronic acid than that from the remaining land plants including the less basal mosses and all vascular plants tested. Polysaccharides of the hornwort Anthoceros contained an unusual repeat-unit, glucuronic acid-alpha(1-->3)-galactose, not found in appreciable amounts in any other plants tested. Galacturonic acid was consistently the most abundant PCW uronic acid, but was present in higher concentrations in acid hydrolysates of bryophytes and charophytes than in those of any of the vascular plants. Mannuronic acid was not detected in any of the species surveyed. (3) Mannose: acid hydrolysis of charophyte and bryophyte PCW-rich material also yielded appreciably higher concentrations of mannose than are found in vascular plant PCWs. (4) Mixed-linkage glucan (MLG) was absent from all algae and bryophytes tested; however, upon digestion with licheninase, PCW-rich material from the alga Ulva lactuca and the leafy liverwort Lophocolea bidentata yielded penta- to decasaccharides, indicating the presence of MLG-related polysaccharides. Our results show that major evolutionary events are often associated with changes in PCW composition. In particular, the acquisition of xyloglucan may have been a pre-adaptive advantage that allowed colonization of land.

Characterization of methyl sugars, 3-deoxysugars and methyl deoxysugars in marine high molecular weight dissolved organic matter

“…In the HSQC spectrum we observed a correlation between βH-3 (3.37 ppm) and a carbon at 82.4 ppm, which we assigned as βC-3, further establishing the site of methylation. There is a cross peak between H-4 (3.45 ppm) and a carbon at 71.4 ppm, which we assigned as βC-4, in good agreement with the values assigned by Popper and Fry (2003) We used the same reasoning to identify F 3 B2 as a α/ß mixture of 2-Omethylrhamnose (XVI) (Zdorovenko et al 2001;Schäffer et al 2002). Fractions F 3 B1…”

“…polysaccharides from a large number of cyanobacteria (Painter, 1983;Shekharam et al 1987;Ogawa et al 1997), and vascular plants (Bacon and Cheshire, 1971;Casagrande et al 1985;Popper and Fry, 2003;Popper et al 2004;Sassaki et al, 2005). These two sugars, together with 3-O-methylglucose and 2-O-methylfucose are common in lipopolysaccharides, part of the outer cell membrane of gram-negative bacteria (Kennedy and White, 1983;Brade et al 1988).…”

Macromolecular and chemical features of the excreted extracellular polysaccharides in induced biological soil crusts of different ages

“…Indeed, in the EPSs extracted from the IBSCs under study, these two monosaccharides were found to be the second and third most abundant sugars respectively, while mannose was found to be the most abundant sugar. Most probably mosses have significantly contributed to the presence of large amount of this sugar, as it is largely present in their cell walls (Popper and Fry, 2003).…”

Occurrence of the Primary Cell Wall Polysaccharide Rhamnogalacturonan II in Pteridophytes, Lycophytes, and Bryophytes. Implications for the Evolution of Vascular Plants

“…Many of the morphological and biochemical changes that allowed plants to adapt to life on land have been documented (Graham, 1993;Niklas, 1997). However, the limited amount of information available on the composition and architecture of non-flowering plant cell walls (Ligrone et al, 2002;Popper and Fry, 2003) is an impediment to understanding the evolutionary origins of cell walls and the changes in wall structure that occurred during the evolution of land plants.All growing plant cells are surrounded by a polysaccharide-rich primary wall. Primary walls regulate cell expansion and also have important roles in plant growth and development, in the defense against micro-organisms (Carpita and Gibeaut, 1993), and in intercellular signaling (Ridley et al, 2001).…”

“…Many of the morphological and biochemical changes that allowed plants to adapt to life on land have been documented (Graham, 1993;Niklas, 1997). However, the limited amount of information available on the composition and architecture of non-flowering plant cell walls (Ligrone et al, 2002;Popper and Fry, 2003) is an impediment to understanding the evolutionary origins of cell walls and the changes in wall structure that occurred during the evolution of land plants.…”