Novel Approaches to Combat Drug‐Resistant Bacteria

Abstract

There is an increasing concern that the need for new antibacterial agents is greater than ever because of the emergence of multidrug resistance in common bacterial pathogens and the rapid emergence of new infections. Despite the critical need for new antibacterial agents, development is declining. Therefore, solutions for encouraging and facilitating the development of new agents are needed. It is believed that sustained success in the long-term battle against bacterial pathogens will require new strategies and new chemical scaffolds that target other cellular processes. In recent years, new antibacterial drug targets have been explored and validated. Some of the vulnerable targets are bacterial quorum sensing, interference with virulence and pathogenicity, drug-resistance mechanisms (efflux pump) and targets based on plasmid physiology. It is expected and believed by many workers that unexplored microbial diversity may provide novel and effective antibacterial drugs, if improved screening strategies are attempted and intelligent test systems are applied. This chapter will discuss recent strategies to obtain novel antibacterials from microbial products to combat drug-resistant bacteria. Further, roles of alternative therapy (phage therapy) and antibiotic use policy are discussed as possible ways to minimize the problem of drug resistant bacteria.

Inhibition of quorum sensing regulated bacterial functions by plant essential oils with special reference to clove oil

“…One of the major problems of antibiotic therapy is the emergence of drug‐resistant bacteria both in hospital and in community‐acquired infection. In view of the slow progress in developments of new antibiotics with novel mode of actions, new strategies have been suggested to combat bacterial infections including inhibition of QS (Fernandes 2006; Ahmad et al. 2009).…”

“…One of the major problems of antibiotic therapy is the emergence of drug-resistant bacteria both in hospital and in community-acquired infection. In view of the slow progress in developments of new antibiotics with novel mode of actions, new strategies have been suggested to combat bacterial infections including inhibition of QS (Fernandes 2006;Ahmad et al 2009). Inhibition of QS systems regulating the expression of virulence factors as well as biofilm formation is a highly attractive target for developing novel therapeutics (Hentzer and Givskov 2003).…”

Antibiofilm Activity of Dendrophthoe falcata against Different Bacterial Pathogens

“…Plant extracts were prepared as described by Ahmad et al [13] with slight modifications. The leaves (25 g) of D. falcata were airdried and grounded to a fine powder using an electronic blender and extracted in a soxhlet extractor with 250 mL of methanol.…”

“…Agar well diffusion assay: The agar well diffusion was performed according to the established method of Ahmad et al [13]. To determine the QS inhibition of the leaf extract, C. violaceum (ATCC 12472) was spread with 0.1 mL of appropriately diluted (~1.5 × 10 6 CFU/mL) freshly grown cultures, and wells of 6 mm in diameter were made.…”

“…Quorum sensing (QS) is a mechanism in which bacteria coordinate gene expression in response to their population density by producing, releasing, and recognizing small signal molecules called autoinducers. Previous anti-infective studies on medicinal plants have concentrated mainly on the antimicrobial potential for traditional use validation or an antimicrobial drug discovery perspective [13]. However, no systematic effort has been made to explore the anti-QS activity of traditionally used Indian medicinal plants with a rich biodiversity.…”