New perspectives on mobile genetic elements: a paradigm shift for managing the antibiotic resistance crisis

Mobile genetic elements (MGEs) are primary facilitators in the global spread of antibiotic resistance. Here, we present novel ecological and evolutionary perspectives to understand and manage these elements: as selfish entities that exhibit biological individuality, as pollutants that replicate and as invasive species that thrive under human impact. Importantly, each viewpoint suggests new means to control their activity and spread. When seen as biological individuals, MGEs can be regarded as therapeutic targets in their own right. We highlight promising conjugation-inhibiting compounds that could be administered alongside antibiotic treatment. Viewed as pollutants, sewage treatment methods could be modified to efficiently remove antimicrobials and the resistance genes that they select. Finally, by recognizing the invasive characteristics of MGEs, we might apply strategies developed for the management of invasive species. These include environmental restoration to reduce antimicrobial selection, early detection to help inform appropriate antibiotic usage, and biocontrol strategies that target MGEs, constituting precision antimicrobials. These actions, which embody the One Health approach, target different characteristics of MGEs that are pertinent at the cellular, community, landscape and global levels. The strategies could act on multiple fronts and, together, might provide a more fruitful means to combat the global resistance crisis. This article is part of the theme issue ‘The secret lives of microbial mobile genetic elements’.

Macrophages in Microbial Pathogenesis: Commonalities of Defense Evasion Mechanisms

Macrophages are key arsenals of the immune system against invaders. After compartmental isolation of a pathogen in phagosomes, the host immune response attempts to neutralize the pathogen. However, pathogens possess the ability to subvert these assaults and can also convert macrophages into their replicative niche. The multiple host defense evasion mechanisms employed by these pathogens like phagosome maturation arrest, molecular mimicry through secretory antigens, interference with host signaling, active radical neutralization, inhibition of phagosome acidification, alteration of programmed cell death and many other mechanisms. Macrophage biology as a part of the host-pathogen interaction has expanded rapidly in the past decade. The present review aims to shed some light upon the macrophage defense evasion strategies employed by infecting pathogens. We have also incorporated recent knowledge in the field of macrophage dynamics during infection and evolutionary perspectives of macrophage dynamics.

March-ing to the beat of a Maverick Drummer: insights from John Boyd to inform behavioral perspectives

Purpose The purpose of this paper is to discuss some of James G. March’s key ideas and extend and integrate them with the works and ideas of John Boyd, whose work is highly relevant to, yet neglected by, behavioral and evolutionary perspectives on decision-making, organizations and strategy. Design/methodology/approach This paper integrates and synthesizes ideas in behavioral organization studies with those of John Boyd. Findings The authors suggest that when integrated, Boydian and Marchian ideas can enrich the understanding of particular ideas and mechanisms identified in behavioral organization studies and help broaden the intellectual and interdisciplinary range of the field in consonance with March’s vision for it. Originality/value The authors combine and integrate ideas central to the field of organization studies with those of an “outsider.”