Antibiotic Resistance is a critical problem
The emergence of Multiple Drug Resistant (MDR) pathogenic bacteria has lessened the effectiveness of antibiotic drugs designed to cure or prevent infections. The issue is so critical that United Nations recently declared it a fundamental threat to global health. Unless concerted global actions are initiated, we will head for the pre-antibiotic era, when common bacterial infections and minor injuries can lead to serious disability or even death. Among the alternative therapeutic techniques, Bacteriophage Therapy has the best potential to act against the threat of MDR bacteria with much lower side effects.
It is to be noted that some bacteria are naturally resistant to certain antibiotics and some can develop resistance by a spontaneous genetic mutation or acquiring antibiotic resistance genes from other bacteria. Antibiotics kill or inhibit the non-resistant bacteria and lets the resistant bacterial strains (superbug) to survive and multiply.
Pathogenic Bacteria frequently live in biofilms
In many different natural and man-made environments, including dental plaques, water pipes etc. pathogenic bacteria is found to reside in biofilms, which are surface-attached aggregates embedded in a matrix of extracellular polymeric substance.
The biofilm matrix comprises of polysaccharides, structural proteins, enzymes, DNA, lipids, and water which protects its inhabitants from environmental challenges thereby allowing long-term colonization. The extracellular polymers or modifying enzymes also inactivate the antibiotics, and furthermore, the localized gradients in biofilm matrix provide zones where the bacterial cells can survive and initiate relapse of the disease.
The cells in the biofilm are closely spaced facilitating communication by the process of quorum sensing, which along with an increased level of mutations is responsible for the growth of the biofilm. It is found to be most likely that the bacteria in biofilms use conjugation mechanism to transfer genes within or between populations and thus develop further antibiotic resistance.
As a consequence, biofilm-specific resistance is usually 1,000-fold higher than antibiotic resistance of planktonic bacteria.
