Biotechnology Archive
Today we have the genome sequences for humans as well as many other animals, plants, fungi, and bacteria. All these data have given scientists a global view of the various genes in humans and others. However, genes are only the …
Individuals who survive an infection normally become immune to that particular disease, although not to other diseases. This is because the immune system “remembers” foreign antigens, a process called immune memory . Next time the same antigen appears, it triggers …
There are many clinical uses for antibodies. They are used in diagnostic procedures (including the ELISA), for pregnancy testing, and to detect the presence of proteins characteristic of particular disease-causing agents. In the future, they may be used …
Depending on the type of heavy chain, antibodies are categorized into different classes, and assume different roles in the immune system. The most abundant and typical antibody has a gamma heavy chain and is called immunoglobulin G (IgG) . IgG …
Each antibody consists of four protein subunits, two light chains and two heavy chains , arranged in a Y-shape. Disulfide bonds between cysteine amino acid residues hold the chains together. Each of the light and heavy chains consists of a …
Antibodies are proteins that recognize and bind to alien molecules. Because there are an almost infinite variety of possible alien molecules, a correspondingly vast number of different antibody molecules are needed. The amino acids making up protein molecules can certainly …
Antigen The term antigen refers to any foreign molecule that provokes a response by the immune system. In practice, most antigens are proteins made by invading bacteria or viruses. In particular, glycoproteins, which carry carbohydrate residues, and lipoproteins, which carry lipid …
The world is full of infectious microorganisms, all looking for a suitable host to infect. Bacteria, viruses, and protozoans are constantly attempting to gain entry into our tissues. If nothing was done about these attempts at invasion, no human could …
Botulinum toxin is the most toxic substance known. It is made by the anaerobic bacterium, Clostridium botulinum , and is the cause of botulism, a severe form of food poisoning. It has been proposed as a biowarfare agent but has …
DNA fingerprinting relies on the unique pattern made by a series of DNA fragments after separating them according to length by gel electrophoresis. DNA samples from different suspects, the victim, and samples from the crime scene are first purified. Restriction …