Toxic effects of nanoplastics on biological nitrogen removal in constructed wetlands: Evidence from iron utilization and metabolism

Water Research, Journal Year: 2024, Volume and Issue: 256, P. 121577 - 121577

Published: April 6, 2024

Language: Английский

---

Multiplicity of type 6 secretion system toxins limits the evolution of resistance

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(2)

Published: Jan. 9, 2025

The bacterial type 6 secretion system (T6SS) is a toxin-injecting nanoweapon that mediates competition in plant- and animal-associated microbial communities. Bacteria can evolve de novo resistance against T6SS attacks, but far from universal natural communities, suggesting key features of weaponry may act to limit its evolution. Here, we combine ecoevolutionary modeling experimental evolution examine how toxin multiplicity Acinetobacter baylyi attackers shape susceptible Escherichia coli competitors. In both our models experiments, find combinations multiple distinct toxins by creating genetic bottlenecks, driving resistant lineages extinct before they reach high frequency. We also show that, paradoxically, single-toxin drive the cross-resistance, protecting bacteria unfamiliar combinations, even though such evolutionary pathways were inaccessible multitoxin attackers. Our findings indicate comparable antimicrobial anticancer combination therapies, arsenals function competing microbes. This helps us understand why T6SSs remain widespread effective weapons many T6SS-armed encode functionally diverse anticompetitor toxins.

Language: Английский

---

Killing by Type VI secretion drives genetic phase separation and correlates with increased cooperation

Nature Communications, Journal Year: 2017, Volume and Issue: 8(1)

Published: Feb. 6, 2017

Abstract By nature of their small size, dense growth and frequent need for extracellular metabolism, microbes face persistent public goods dilemmas. Genetic assortment is the only general solution stabilizing cooperation, but all known mechanisms structuring microbial populations depend on availability free space, an often unrealistic constraint. Here we describe a class self-organization that operates within densely packed bacterial populations. Through mathematical modelling experiments with Vibrio cholerae, show how killing adjacent competitors via Type VI secretion system (T6SS) precipitates phase separation ‘Model A’ universality order-disorder transition mediated by killing. We mathematically demonstrate T6SS-mediated should favour evolution empirically support this prediction using phylogenetic comparative analysis. This work illustrates twin role played T6SS, dealing death to local while simultaneously creating conditions potentially favouring cooperation kin.

Language: Английский

---

The evolution of siderophore production as a competitive trait

Evolution, Journal Year: 2017, Volume and Issue: 71(6), P. 1443 - 1455

Published: March 22, 2017

Microbes have the potential to be highly cooperative organisms. The archetype of microbial cooperation is often considered secretion siderophores, molecules scavenging iron, where threatened by "cheater" genotypes that use siderophores without making them. Here, we show this view neglects a key piece biology: are imported specific receptors constrain their competing strains. We study effect specificity in an ecoevolutionary model, which vary siderophore sharing among strains, and compare fully shared with private siderophores. privatizing fundamentally alters evolution. Rather than canonical good, become competitive trait used pillage iron from other also physiological regulation using silico long-term Although evolve downregulated presence competitor, as expected for trait, privatized upregulated. evaluate these predictions published experimental work, suggests some upregulated response competition akin traits like antibiotics. can act good single genotypes, argue role fundamental understanding biology.

Language: Английский

---

Experimental evolution in biofilm populations

FEMS Microbiology Reviews, Journal Year: 2016, Volume and Issue: 40(3), P. 373 - 397

Published: Feb. 18, 2016

Biofilms are a major form of microbial life in which cells dense surface associated communities that can persist for many generations. The long-life biofilm means they be strongly shaped by evolutionary processes. Here, we review the experimental study evolution communities. We first provide an overview different models used to and their advantages disadvantages. then illustrate vast amount diversification observed during evolution, discuss (i) potential ecological processes behind diversification, (ii) recent insights into genetics adaptive (iii) striking degree parallelism between experiments real-life biofilms (iv) consequences diversification. In second part, provided how growth structure promote cooperative phenotypes. Overall, our analysis points important role cooperation bacterial survival productivity. Deeper understanding both is key importance design improved antimicrobial strategies diagnostic techniques.

Language: Английский

---