INTRODUCTION
Plants
use carbon dioxide and water to produce glucose through the process of
photosynthesis. The combination of glucose with other monosaccharide gives
starch and cellulose. Energy is stored in plants in form of carbohydrate, thus
carbohydrate is known as the energy giving food. The energy giving food is
composed majorly of carbon, hydrogen and oxygen and has the general molecular
formula Cx(H20)y. Carbohydrates can be classified naturally into
simple sugar which include the monosaccharide e.g. glucose, fructose, mannose
and galactose, the disaccharides (formed from the condensation of two monosaccharide
with the loss of a water molecule) e.g. sucrose, maltose and lactose. Complex
sugar also called polysaccharides (formed from the condensation of more than
two monosaccharide) e.g. starch, glycogen and cellulose. Carbohydrate is
commonly, found on fruits, sap of plants e.g. tuber plants and grain crops. And
also in honey.
Glycobiology is the study of the structure, biosynthesis, chemical synthesis and biology of saccharide (sugar chains or glycans). The importance of sugar can never be over emphasized since it is an essential component of living organism and it serves as the major sources of energy. According to the research done by various fields like medical, biochemical and biotechnological field sugar plays an important role in biology.
In the broadest sense glycobiology can be defined as the study of the roles of carbohydrates in cellular life. Often they are continently bound to proteins (glycoproteins) and lipids (glycololipids to form glycoconjugates. Many glycol conjugates have structural roles. However, the carbohydrates groups of gylycoconjugates also can be involved in cellular processes including adhesion, transformation, growth, endocytosis and fertilization.
CHAPTER
ONE
1.0 OCCURRENCE AND PRODUCTION
The occurrence of
glycobiology in the living cells include the following.
1. The
outer membrane of all living cells in nature is majorly composed of a dense and
complex array of sugar chains (glycans).
2. Many
classes of glycans and glycoconjugates is found on the bacteria and archea cell
walls.
3. In
eukaryotic organism most of proteins been secreted contains very large amount
of covalently bond glycans.
4. Also in eukaryotes, the cells surface and secreted glycans are mostly assembled via the Endoplasmic Reticulum – Golgi pathway.