The BioPorto range of monoclonal antibodies includes clones targeting bacteria antigens and toxins, for use in ELISA and Western Blot applications.
Targets include Gram-positive bacteria such as Clostridium
(C.botulinum and C.tetani), Corynerbacterium diptheriae
toxoid and Streptococcal toxins pneumolysin and
streptolysin. Antibodies are also available for detection of
polio and flu viruses.
Bacteria are prokaryotic organisms with no nucleus or other membrane bound organelles that occur in a variety of shapes from spherical and rod-shaped to spiral. They are often divided based upon their uptake of the Gram stain, as Gram-positive and Gram-negative. Found in almost every habitat, from soil and water to acidic hot springs and radio active waste, these microorganisms are vital for nutrient recycling. Some bacteria also form symbiotic relationships with other animals, such as the mutalism that exists in the human digestive tract enabling the digestion of certain starches and sugars. However, other bacteria are pathogenic causing infection and disease.
Clostridium botulinum is a Gram-positive, rod-shaped bacterium commonly found in soil. This anaerobic spore-forming organism produces a variety of toxins, in particular a series of neurotoxins responsible for the muscular paralysis seen in botulism. The neurotoxins, subdivided into types A-G are only produced during sporulation and are a feature of the C.botulinum species. Whiles most strains produce only one form of toxin, some multiple toxin producing strain have been described. Types A, B, E and F cause disease in humans, whilst types C and D cause disease in birds and other animals. Type A is used cosmetically to reduce the appearance of frown lines. Clostridium botulinum type E is prevelant in aquatic sediments in Norway, Sweden, Denmark the Netherlands and Baltic Coast.
Clostridium Tetani is another Gram-positive, rod shaped bacteria belonging to the genus Clostridium.This anaerobic bacterium is found as spores in soil or in the gastrointestinal tract of animals and produces the potent neurotoxin tetanospasmin which causes tetanus. Clostridium Tetani typically enters the host through a wound in the skin and begins to replicate. Tetanospasmin is a zinc-dependent metalloproteinase produced when the bacteria lyse during spore germination or vegetative growth. Whilst structurally similar to botulinum toxin, tetanospasmin has different effects.
Tetanus is characterised by painful muscular spasms that can lead to respiratory failure and death. Once released into the circulation tetanospasmin binds peripheral motor neuron terminals and is transported across synaptic junctions until it reaches the central nervous system. Here it binds gangliosides in the presynaptic membrane of inhibitory motor neurones. Tetanus toxin blockade of inhibitory impulses results in an increase in the firing rate of the alpha motor neurones producing rigidity, unopposed muscle contraction and spasm.
Mycobacterium Tuberculosis is an aerobic bacterium with that is neither Gram-positive nor Gram-negative, a high lipid content in the cell wall prevents staining. Typically acid-fast methods of staining are used for identification. M tuberculosis is primarily a pathogen of the mammalian respiratory system and infects the lungs. It is taken up by alveolar macrophages but the bacterium cell wall prevents fusion of the phagosome with a lysosome so the pathogen is not digested but instead replicates within the macrophage.
M tyberculosis secretes various proteins such as early release secretory antigen target 6 (ESAT-6), Antigen 85 and A-alanine dehydrogenase (Ald) which can elicit antibody responses and may play important roles in protective immunity.
Corynebacterium diptheriae are Gram-Positive, rod-shaped bacteria and some strains secrete an exotoxin that causes diphtheria. Diptheria is an upper respiratory tract disease, characterised by sore throat, fever and a pseudomembrane on the tonsils, pharynx and nasal cavity. The diphtheria toxin can also cause myocarditis and polyneuritis and mortality rates can be as high as 20% in young children and older adults.
The diphtheria toxin gene is encoded by a bacteriophage, a virus that infects bacteria, and is not part of the bacterium genome. Only strains lysogenised by a specific beta phage produce diphtheria toxin. The toxin binds to HB-EGF receptors and enters the host cell by receptor mediated endocytosis. Once in the cytoplasm the diphtheria toxin inhibits protein synthesis ultimately leading to host cell death.
Streptococcus pneumoniae is a Gram-positive, spherical, aerotolerant anaerobic bacterium and a major cause of bacterial pneumonia, sinusitis, otits media, meningitis and other pneumococcal diseases. Pneumolysin is the major cytotoxin produced by S pneumoniae, it facilitates colonisation and attacks host cells by creating pores in cholesterol containing membranes that resulting in cell lysis. S pneumoniae is an alpha-haemolytic species of Streptococcus causing oxidation of iron in haemoglobin.
Streptococcus pyrogenes is the causative agent in streptococcal infections such as streptococcal pharygitis (“strep throat”), scarlet fever and necrotizing fasciitis. Gram-positive and spherical, S pyrogenes displays the streptococcal group A antigen on its cell wall. As a beta-heamolytic species it causes the complete disruption of erythrocytes and release of haemoglobin. S pyrogenes produce an exotoxin called streptolysin which produces the haemolytic effect. Streptolysin exists in two forms oxygen label (streptolysin-O) and oxygen stable (streptolysin-S). The later is smaller and non-antigenic whilst measurement of antibodies detecting streptolysin-O, the ASO test, can be used to confirm recent infection