The effect of shortining glycan chains linked to the cationic peanut Dissertation

The effect of shortining glycan chains linked to the cationic peanut peroxidase on its activity - Dissertation Example Recent studies have gone further to discover linkages between other sugars like D-Glc, L-Rha and D-GaiNAc and ASn in bacteriai glycoproteins (Neuhoff, 1999). Glycans Structural Features The process of examining glycan sytructures in large numbers has shown that there exist a number of rules which include; the glycans that are N-linked indicate a common Mannotriosedi and N-acetlylchitobiose structural pattern which is linked to a residue of Asn. Most of the plants containing glycoproteins have a residue of Xyl that is attached via f3-1 to 2 linkage extending towards the core of the p-linked Man. The link in some cases extends to GLcNAc proximal via a a-1, 3 bond involving glycoside. The second rule is that the glycans N-linked, with reference to the antenna structures they have, can be easily put into three categories (Neuhoff, 1999). 1. The aligomannose kind where the antennae substitute can only be achieved through adding Man residues 2. Complex type where the its antennae is made u p of Fuc, GlcNac, Sia and Gd together with Man residues 3. Hybrid type; this is a representation of the two above types. In the past, the above was believed to only take place in animals yeast and in some cases fungal glycoproteins. Recent studies on agglutinin structure show that such glycans are also found in glycoproteins of higher plants. Glycans come in varied forms from a residue of a single Ga1 to a structure that is branched with more than 20 residues of monosaccharide. The mucins O-glycans which form the most glycoproteins containing O-glycans, show heterogeneity that are extreme with a good number of oligosaccharide per molecule. Although the core structure concept can be extrapolated to O-glycans, its essence is not the same as there exists seven 0-linked classes core and they in most cases come as trisaccharides or disaccharides (Dwek, 2009). Cationic Peanut Peroxidase On Its Activity By looking at the ribosome which are both free and membrane bounded, the process of iso lation of the poly (A)- having mRNA for the entire polysomal RNA , it has been decided that approximately 2 % of the total protein synthesis have been slated for cationic peroxidase (CPRx) (Dwek, 2009).At the same time, the two fractions that are minor for the other two isozymes can be used as a confirmation of the three isozymes found in the acetone isolated pellet. The use of peptide mapping however shows that the three peroxidase isozymes contained different sequences of amino acids. In this case, the protein pellets that have been isolated recorded the highest nm ratio of a bout 403/480. This shows that that they pellets contain high protein heme ratio indicating purity. As the absorption bands of normal amino acids are the simplest near UV, there are a number of suggestions on ways of detecting the protein structure in relation to the sequence of amino acids through spectroscopic analysis. The isolated CPRx has an absorbance of 403 nm and appears to be red in color. These chara cteristics have been associated with the heme presence containing iron as this in required for the activity of enzymes. However, not all the iron having proteins are definitely heme proteins. There exist a number of enzymes that are in need of iron a part from peroxidase with other enzymes having different enzyme requirements. In CPRx, its cells grow in the iron presence in the medium that is suspended. A peroxide secretion loss takes place in the