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71.
Summary Physiological and ultrastructural studies of unialgal cultures demonstrated that silicon is a required nutrient and a component of the cell walls of Cladophora glomerata. Addition of silicon promoted growth of the alga, and the addition of germanium, an analogue of silicon, inhibited growth of C. glomerata in culture. An electron-dense outer layer was a conspicuous part of the cell walls of filaments taken from silicon rich medium.Abbreviation SWE
soil water extract 相似文献
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Spermatium formation in G. juniperi-virginianae is phialidic. The spermatia are blown out of the tips of spermatiophores which possess a thickened neck region and a distinct, flared collarette. Each spermatium initial is surrounded by a thin wall which is attached to the inner surface of the spermatiophore wall just below the thickened neck region. A spermatium is delimited by a centripetally developing septum and then pushed into the spermogonial cavity by the next spermatium initial. Mature spermatia are ellipsoid with tapered ends and are surrounded by a thin wall. Each contains a single nucleus, many ribosomes, a few small vacuoles, and a number of lipid bodies and mitochondria. 相似文献
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Pascal Bonnarme Serge Moukha Patrick Moreau Eric Record Laurence Lesage Claude Cassagne Marcel Asther 《FEMS microbiology letters》1994,120(1-2):155-161
Abstract Mycelia from the basidiomycete Phanerochaete chrysosporium , producing lignin and manganese peroxidases, were homogenized and fractionated on a sucrose gradient. The main subcellular fungal membrane fractions were successfully separated. Lipid composition analyses of the isolated membranes as well as associated marker enzymes distribution gave evidence to similarities with membranes originating from plants. Lignin and manganese peroxidases were investigated by immunodetection in subcellular fractions. Our results show that lignin and manganese peroxidases are mainly associated with Golgi apparatus vesicles and, to a lesser extent, with endoplasmic reticulum and light density vesicles, but not with plasma membranes. 相似文献
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