Marine macroalgae and their associated microbiomes as a source of antimicrobial chemical diversity

Abstract

Antimicrobial resistance (AMR) represents one of the major health threats faced by humanity over the next few years. To prevent a global epidemic of antimicrobial-resistant infections, the discovery of new antimicrobials and antibiotics, better anti-infection strategies and diagnostics, and changes to our current use of antibiotics have all become of paramount importance. Numerous studies investigating the bioactivities of seaweed extracts as well as their secondary and primary metabolites highlight the vast biochemical diversity of seaweeds, with new modes of action making them ideal sources for the discovery of novel antimicrobial bioactive compounds of pharmaceutical interest. In recent years, researchers have focused on characterizing the endophytic and epiphytic microbiomes of various algal species in an attempt to elucidate host-microbe interactions as well as to understand the function of microbial communities. Although environmental and host-associated factors crucially shape microbial composition, microbial mutualistic and obligate symbionts are often found to play a fundamental role in regulating many aspects of host fitness involving ecophysiology and metabolism. In particular, algal "core" epiphytic bacterial communities play an important role in the protection of surfaces from biofouling, pathogens and grazers through the production of bioactive metabolites. Together, marine macroalgae and their associated microbiomes represent unique biological systems offering great potential for the isolation and identification of novel compounds and strategies to contrast the rise and dissemination of AMR.

The seaweed holobiont: from microecology to biotechnological applications

“…In addition, seaweed and their endophytic symbionts are a good source of bioactive secondary metabolites (Fig. 2 ), which are described in the subsections below, and can provide stress tolerance to the continuous stresses that macroalgae are exposed to in marine environments, such as prolonged sunlight exposure, moisture and salt concentration variation, tidal changes and numerous microorganisms and herbivorous insects, because of secondary metabolites (Busetti et al ., 2017 ; Sarasan et al ., 2017 ; Teixeira et al ., 2019 ; Menaa et al ., 2020 ).…”

Understanding the metabolome and metagenome as extended phenotypes: The next frontier in macroalgae domestication and improvement

“…Application of these methods to macroalgae domestication is a unique opportunity and a powerful tool for research in agriculture and microbiomes because macroalgae is a fast-growing organism and its overall fitness is tightly intertwined with the native microbiome ( Busetti, Maggs, & Gilmore, 2017 ; Egan et al, 2013 ; Florez, Camus, Hengst, & Buschmann, 2017 ; Laycock, 1974 ; Tello et al, 2019 ).…”

Ecological and Industrial Implications of Dynamic Seaweed-Associated Microbiota Interactions

“…Therefore, it is thought that the induction of virulence factors are liable for pathogen–host association [ 81 ]. Several reports indicated that numerous aquatic organisms like microalgae, macroalgae, invertebrates, or maybe other bacteria have the potential to disrupt QS [ 119 ]. Importantly, the disruption of bacterial communication by QS is considered as a novel and environmentally friendly approach to avoid harmful consequences for the algal health and fecundity.…”