Cell wall The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicelluloses and pectin. Often, other polymers such as lignin, suberin or cutin are anchored to or embedded in plant cell walls. Algae possess cell walls made of glycoproteins and polysaccharides such as carrageenan and agar that are absent from land plants. In bacteria, the cell wall is composed of peptidoglycan. The cell walls of archaea have various compositions, and may be formed of glycoprotein S-layers, pseudopeptidoglycan, or polysaccharides. Fungi possess cell walls made of the N-acetylglucosamine polymer chitin. Unusually, diatoms have a cell wall composed of biogenic
Insect cell culture culture. Insect cell culture The use of insect cell lines as production hosts is an emerging technology for the production of bio pharmaceuticals. There are currently more than 100 insect cell lines available for recombinant protein production with lines derived from "Bombyx mori", "Mamestra brassicae", "Spodoptera frugiperda", "Trichoplusia ni", and "Drosophila melanogaster" being of particular interest. Insects cell lines are commonly used in place of prokaryotic ones because post-translational modifications of proteins are possible in insect cells whereas this mechanism is not present in prokaryotic systems. The Sf9 cell line is one of the most commonly used lines in insect