Amino acid-based molecules to combat bacterial infections and resistance

Abstract

Infectious diseases were the primary cause of death prior to the discovery and use of antimicrobial drugs and even today it remains as one of the major killers of mankind.1 Even though, the viral disease outbreaks such as Severe Acute Respiratory Syndrome (SARS), bird flu, swine flu, Ebola, Nipah and Zika have apprehended the attention in the recent history,2-8 the experts in the field say that even more serious threat to public health may be present in the skyline due to the rampant emergence of antibiotic-resistant bacteria.8-13 The Centers for Disease Control and Prevention (CDC) reported that every year, some 2 million people get infected with antibiotic-resistant bacteria and at least 23,000 people die as a result of such infections in the United States alone.12 The European Centre for Disease Prevention and Control (ECDC) has also estimated that antibiotic-resistant bacteria kill nearly 25,000 Europeans annually.13 The situation could be imagined even worse in the developing nations. Indians face a greater risk of being affected by infectious diseases.14 The Global Antibiotic Resistance Partnership (GARP) has reported that India has occupied the highest position in occurance of bacterial diseases among the world.15 Streptococcus pneumoniae causes death of 4,10,000 lives each year.16 Many children die due to this bacterium, especially those from economically impaired families.17 The alarm has already been set by various organizations all over the world, calling for urgent development of new class of antibacterial drugs. Recently, the World Health Organization (WHO) declared an unparalleled warning, listing a dozen of antibiotic-resistant bacteria responsible for the majority of diseases to human.10,11 According to the urgency of need for new antibiotics, WHO has divided these bacteria into three different catagories, critical, high and medium priority. Carbapenem-resistant strains of Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacteriaceae have been catagorised in the critical-priority list. According to current senario, there is no effective therapy present in the clinic for treatment of the infections caused the multi-drug-resistant strains of these pathogens. The infections caused by these critical pathogens can lead to severe life-threatening illnesses including bacteremia, pneumonia, meningitis, urinary tract infection (UTI), wound infection, etc.18 In the second category, total six bacteria have been included in high-priority list. Three of them are methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus faecium, and Neisseria gonorrhoeae.