Login With Google
Aptamer inhibits TB bacteria entry into cells
Why is it in news?
- By using a small single-stranded DNA molecule (DNA aptamer) that specifically binds to a single protein (HupB) present in TB bacteria, researchers have been able to achieve 40-55% reduction in the bacteria’s ability to enter into human cells and infect them.
- Besides facilitating entry into host cells, HupB also helps the TB bacteria survive various stresses encountered inside host cells.
More in news
- The HupB protein was discovered in late 1990s by Prof. H. Krishna Prasad, formerly with AIIMS, while looking at specific TB bacterial antigens that induced immune response in humans.
- He found the protein was associated with the DNA of the bacteria (Tubercle and Lung Disease journal).
- The TB bacteria use a number of proteins to enter host cells. But their entry into host cells is inhibited 40-55% when the HupB protein alone is inhibited. This shows how vital the HupB protein is in modulating the bacterial entry into host cells.
- Using the HupB protein alone, the researchers tested the ability of the aptamers to inhibit DNA binding.
- At 75%, the HupB-4T aptamer showed greater DNA binding inhibition than the HupB-13T aptamer (25%).
- Inhibition of DNA binding will make the bacteria vulnerable to stress inside the host cells, leading to death.
What are Aptamers?
- Aptamers are oligonucleotide or peptide molecules that bind to a specific target molecule.
- Aptamers are usually created by selecting them from a large random sequence pool, but natural aptamers also exist in riboswitches.
- Aptamers can be used for both basic research and clinical purposes as macromolecular drugs.
- Aptamers can be combined with ribozymes to self-cleave in the presence of their target molecule.
- These compound molecules have additional research, industrial and clinical applications.
- More specifically, aptamers can be classified as
- DNA or RNA or XNA aptamers. They consist of (usually short) strands of oligonucleotides.
- Peptide aptamers. They consist of one (or more) short variable peptide domains, attached at both ends to a protein scaffold.
Source
The Hindu