Dr Colin Kenyon, leader of the CSIR structural biology research group.

CSIR researchers have made a breakthrough in isolating five compounds that show efficacy against X-DR TB (extensively drug-resistant tuberculosis) - the deadly and virulent strain of tuberculosis. X-DR refers those strains of TB resistant to both first and second line drugs - strains that leave infected people virtually untreatable with currently available anti-TB drugs.

According to the World Health Organisation, X-DR TB has been identified in all regions of the world and is found most frequently in the countries of the former Soviet Union and in Asia. In South Africa, it has resulted in more than 200 deaths since being reported for the first time late last year.

Dr Colin Kenyon, leader of the structural biology research group and a contributor to the SERA-initiated African Centre for Gene Technologies (ACGT), says that the CSIR's investigation into inhibitors against these X-DR TB strains follows an Innovation Fund project aimed at developing inhibitors to Mycobacterium tuberculosis - the bacterium that causes most cases of TB.

The structural biology group is based in Modderfontein. It's research that primarily focuses on infectious diseases includes the validation of potential new drug targets. The findings are used for rational inhibitor design and lead molecule modification. The group found several compounds inhibitory to Mycobacterium tuberculosis while working on the isolation of novel antibiotics by rational drug design using computational techniques, organic synthesis and molecular biology.

"It was decided to determine if these same compounds are also inhibitory to X-DR TB," said Kenyon. The research was conducted in conjunction with Stellenbosch University in September. The selection of the 200 compounds initially tested, was based on the results of a novel invitro-screening programme that that included the discovery of a new anti-bacterial target. None of the compounds that successfully passed the X-DR TB screening test were found to be cyto-toxic. "They were found to kill X-DR. What is of significance, is that the inhibition of Mycobacterium tuberculosis by these compounds is not strain dependent," said Kenyon.

The value of this groundbreaking research is reinforced by the European Union's commitment to invest in the expansion of this project. The structural biology group has also approached the Innovation Fund for financial assistance.

Source: CSIR