A new boost to anti-TB crusade
Tuberculosis (TB), could be fought more effectively in the future. The Centre for DNA Fingerprinting and Diagnostics in Hyderabad (CDFD), has gained new insights into the molecular mechanism that allows the TB bacterium to escape the immune system.
Since the dawn of human civilization, TB has been associated to mankind. It is caused by Mycobacterium tuberculosis, a bacterium. It moves through the air, passing from one person to another until it reaches its home in the lungs. Tuberculosis can be treated quickly and properly. A rapid and sophisticated detection system is needed to diagnose tuberculosis. This could be a smoke detector or a fire alarm. Important virulent M.tb proteins are important to TB management and care. Many of these proteins are part of the M.tb arsenal, which helps the bacterium avoid and weaken host immune-responses. One example is PPE2, a protein that helps the bacterium to avoid and weaken host immune-responses.
The group of researchers previously discovered that PPE2 protein blocks the production of reactive nitrogen species (RNS), and reactive oxygen substances (ROS), which are key components of the immune system.
New insights have been gained that suggest that PPE2 may also play an important role in controlling the synthesis Vitamin B12 in bacteria. Vitamin B12 is essential for gene regulation and bacterial metabolism. Vitamin B12 cannot be synthesized by the human body. Instead, it is dependent on external food supplements and gut microbiota to provide Vitamin B12. M.tb however, has genes that allow for Vitamin B12 synthesis. It is not known what the Vitamin B12 pathway looks like in M.tb. This is what the new study provides insight into.
One striking feature of M.tb biology is the presence of a regulatory element or riboswitch within a cluster genes known as an operon. This unit of DNA's DNA is called an operon. There are three genes in the cluster - cobq, cobu and ppe2. Although cobq genes and cobu are part of Vitamin B12 biosynthesis, little is known about PPE2.
This new study helped to unravel some of the mysteries. This study revealed that PPE2 could bind DNA before operon ppe2-cobq–cobu, suggesting that the PPE2 protein may play a role in regulation of the ppe2-cobq1–cobu cluster.
India Science Wire spoke to Dr. Sangita Mukhopadhyay, who stressed that this was just a first step, and that more research is required to understand the mechanism. She said that Vitamin B12 plays a crucial role in bacterial metabolism as well as gene regulation. If the ppe2-cobq1 cobu cluster and riboswitch are thoroughly investigated, it may be possible to transform basic knowledge about microbial metabolism into useful therapeutic methods.