Ciencia Colombia , Bogotá D.C., Martes, 20 de octubre de 2015 a las 10:13

Approach to a tuberculosis vaccine

Universidad Nacional de Colombia (UNal) researchers are working on protein structures with bactericide properties which are fundamental for survival of tuberculosis causing microorganisms

UN/DICYT Tuberculosis treatment consists of a combination of drugs which if used correctly successfully controls the disease. However when patients do not follow the treatment correctly or use low quality antibiotics for long periods of time, the consequence is emergence of antibiotic resistant mycobacteria (Mycobacterium tuberculosis).


In a study for new anti-tuberculosis drugs, the UNal Mycobacteria Biochemistry and Molecular Biology Research Group (BBMM, for its Spanish acronym) is researching the potential usefulness of antibiotic peptides, a type of molecules formed by several amino acids present in proteins to help control bacteria. Up to now they have observed that some innate response peptides have antimicrobial activity.


“Organisms have natural defense mechanisms and we are using natural compounds organisms use to fight primarily skin surface bacteria. After a chemical process, these molecules are modified making them more useful to combat Mycobacterium tuberculosis,” said Carlos Yesid Soto, the director of the research project.


Chemistry doctoral candidate Sandra Milena Chingate added that activity of antimicrobial peptides have a positive effect when it comes to battling tuberculosis and may be from different species. The role of said molecules is to inhibit lipobacteria growth.


Professor Soto says that these peptides are produced by this organism but the BBMM is also producing them in the lab by using a solid phase resin to which they add amino acids in order to produce determined length peptides, for instance peptides with fifteen amino acids. “What we did was change the sequence of some amino acids to increase their antibacterial value,” he said.


Therefore, highlighted Soto, they have observed important alterations in cell wall microstructures in latent tuberculosis mycobacteria that suggest possible composition changes in lipid content, which is relevant in modulating immune response and virulence of these microorganisms.


Then master’s candidate and group member Laudy Viviana Quitián says that the project is based in protein structures with bactericide properties, in other words they are basic membrane transporters for bacteria survival.


The researchers agree that the relevance of this research project is to develop new drugs and a possible vaccine which is a molecular approach as conventional drugs have not been entirely successful.