Virus glycosylation mechanism

For other plant-derived antibodies, stability was shown to be similar to mammalian counterparts. For instance, a humanized anti-herpes simplex virus monoclonal antibody (IgGl) was expressed in soybean and showed stability in human semen and cervical mucus over 24 h similar to the antibody obtained from mammalian cell culture. In addition, the plant-derived and mammalian antibodies were tested in a standard neutralization assay with no apparent differences in their ability to neutralize HSV-2. As glycans may play a role in immune exclusion mechanisms in mucus, the diffusion of these monoclonal antibodies in human cerival mucus was tested. No differences were found in terms of the prevention of vaginal HSV-2 transmission in a mouse model, i.e. the plant-derived antibody provided efficient protection against a vaginal inoculum of HSV-2 [58]. This shows that glycosylation differences do not necessarily affect efficacy. 

Secondly, based on amino acid sequence similarity, chitinolytic enzymes are grouped into families 18, 19, and 20 of glycosyl hydrolases (Henrissat and Bairoch, 1993). Family 18 is diverse in evolutionary terms and contains chitinases from bacteria, fimgi, viruses, animals, and some plant chitinases. Family 19 consists of plant chitinases (classes I, II, and IV) and some Streptomyces chitinases (Hart et al., 1995). The chitinases of the two families, that is, 18 and 19, do not share amino acid sequence similarity. They have completely different 3-D structures and molecular mechanisms and are therefore likely to have evolved from different aneestors (Suzuki et al., 1999). Family 20 includes P-N-acetylhexosaminidases from bacteria, streptomycetes, and humans (Dahiya et al., 2006). 

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