Страна 1 од 59 резултати
Glucans of fungal origin have been shown to inhibit the early stages of infection of Nicotiana by numerous viruses of different taxonomic groups. Several glucans were isolated from the cell walls of Phytophthora parasitica, Phytophthora megasperma f. sp. glycinea (Pmg) and Fusarium oxysporum, and
An important component of barley cell walls, particularly in the endosperm, is (1,3;1,4)-β-glucan, a polymer that has proven health benefits in humans and that influences processability in the brewing industry. Genes of the cellulose synthase-like (Csl) F gene family have been shown to be involved
Two genes for prepro glucan endo-1,3-beta-glucosidase (1,3-beta-glucanase; 1,3-beta-D-glucan glucanohydrolase, EC 3.2.1.39) of tobacco were cloned and their sequences were compared with cDNA clones. Southern analysis indicates that the genomic clones represent genes derived from ancestral parents of
Plant class I glucan endo-1,3-beta-glucosidases (beta-1,3-glucanase; 1,3-beta-D-glucan glucanohydrolase, EC 3.2.1.39) have been implicated in development and defense against pathogen attack. Nevertheless, beta-1,3-glucanase deficiencies generated by antisense transformation of Nicotiana sylvestris
A high level of activity of a β-1,3-glucan hydrolase is present in leaves of Nicotiana glutinosa and the enzyme is also present in the roots, midribs, petioles and stems. By comparison, very low levels of β-1,4-glucan hydrolase are found throughout the plant. The activity of the β-1,3-glucan
The active sites of a spectrum of beta-glucan endohydrolases with distinct, but related substrate specificities have been probed using a series of epoxyalkyl beta-glycosides of glucose, cellobiose, cellotriose, laminaribiose, laminaritriose, 3O-beta-D-glucosyl-cellobiose and
The protein NaGSL1 (Nicotiana alata glucan synthase-like 1) is implicated in the synthesis of callose, the 1,3-beta-glucan that is the major polysaccharide in the walls of N. alata (flowering tobacco) pollen tubes. Here we examine the production, intracellular location and post-translational
Sulfate substituents naturally occurring in biomolecules, such as oligosaccharides and polysaccharides, can play a critical role in major physiological functions in plants and animals. We show that laminarin, a beta-1,3 glucan with elicitor activity in tobacco (Nicotiana tabacum), becomes, after
Cellulose synthase-like F6 (CslF6) genes encode polysaccharide synthases responsible for (1,3;1,4)-β-glucan biosynthesis in cereal grains. However, it is not clear how both (1,3)- and (1,4)-linkages are incorporated into a single polysaccharide chain and how the frequency and arrangement of the two
Mixed-linkage glucan (MLG) is a cell wall polysaccharide containing a backbone of unbranched (1,3)- and (1,4)-linked β-glucosyl residues. Based on its occurrence in plants and chemical characteristics, MLG has primarily been associated with the regulation of cell wall expansion due to its high and
The walls deposited by growing pollen tubes contain two types of beta-glucan, the (1,3)-beta-glucan callose and the (1,4)-beta-glucan cellulose, as well as various alpha-linked pectic polysaccharides. Pollen tubes of Nicotiana alata Link et Otto, an ornamental tobacco, were therefore used to
(1,3;1,4)-β-D-glucans (mixed-linkage glucans) are found in tissues of members of the Poaceae (grasses), and are particularly high in barley (Hordeum vulgare) grains. The present study describes the isolation of three independent (1,3;1,4)-β-D-glucanless (betaglucanless; bgl) mutants of barley which
Although cyclic glucans have been shown to be important for a number of symbiotic and pathogenic bacterium-plant interactions, their precise roles are unclear. Here, we examined the role of cyclic beta-(1,2)-glucan in the virulence of the black rot pathogen Xanthomonas campestris pv campestris
Plants survey their environment for the presence of potentially harmful or beneficial microbes. During colonization, cell surface receptors perceive microbe-derived or modified-self ligands and initiate appropriate responses. The recognition of fungal chitin oligomers and the subsequent activation
Wall-bound purple acid phosphatases have been shown to be potentially involved in the regulation of plant cell growth. The aim of this work was to further investigate the function of one of these phosphatases in tobacco (Nicotiana tabacum), NtPAP12, using transgenic cells overexpressing the enzyme.