Overview of the Fungal Cell Structure

overview of the fungal cell structure fungi are eukaryotic organisms and are not related to bacteria as eukaryotes they contain membranebound organel and possess cell membrane surrounded by a rigid cell wall fungi occur in two basic forms or stages yeast are unicellular whereas filamentous and mold forms are a vegetative growth of filaments fungal filaments are also known as hyi which may be septate or non-septate the cell membrane of fungi is similar to that of other eukaryotic cells and is composed of a lipid bilayer with proteins embedded within it a major component of the eukaryotic cell membrane

is the presence of sterols which are virtually absent from all procaryotes such as bacteria ergosterol is an essential stero in the fungal cell membrane the fungal cell wall is made up of 80 to 90% polysaccharides in yeast the cell wall contains several different polysaccharides including glucans Polymers of glucose manin a polymer of Manos and kiten a polymer of n acety glucosamine glucan is the major component of the fungal cell wall accounting for 30 to 60% of the cell wall of yeasts such as candida species the cell wall of filamentous fungi differs somewhat from that of

yeast and contains a higher concentration of kiten the glucan synthes complex located in the fungal cell membrane is responsible for the synthesis of beta 13 glucan glucan synthesis occurs on the cytoplasmic side of the fungal membrane as glucan chains are synthesized they extrude toward the perlas space where they are then incorporated into the cell wall in most fungi ergosterol replaces the cholesterol component found in higher eukaryotic cell membranes ergosterol provides stability and flexibility to the fungal cell membrane although many enzymes are involved in the formation of ergosterol the 14 Alpha demethylase enzyme is responsible for

the c14 alpha deethylation of lanosterol 14 Alpha demethylate is a cytochrome p450 dependent enzyme which is essential for ergosterol formation once formed ergosterol is incorporated into the fungal cell membrane