
@article {150944,
	title = {Cell shape affects bacterial colony growth under physical confinement.},
	journal = {Nat Commun},
	volume = {15},
	year = {2024},
	month = {2024 Nov 08},
	pages = {9561},
	abstract = {<p>Evidence from homogeneous liquid or flat-plate cultures indicates that biochemical cues are the primary modes of bacterial interaction with their microenvironment. However, these systems fail to capture the effect of physical confinement on bacteria in their natural habitats. Bacterial niches like the pores of soil, mucus, and infected tissues are disordered microenvironments with material properties defined by their internal pore sizes and shear moduli. Here, we use three-dimensional matrices that match the viscoelastic properties of gut mucus to test how altering the physical properties of their microenvironment influences the growth of bacteria under confinement. We find that low aspect\&nbsp;ratio (spherical) bacteria form compact, spherical colonies under confinement while high aspect\&nbsp;ratio (rod-shaped) bacteria push their progenies further outwards to create elongated colonies with a higher surface area, enabling increased access to nutrients. As a result, the population growth of high aspect\&nbsp;ratio bacteria is, under the tested conditions, more robust to increased physical confinement compared to that of low aspect\&nbsp;ratio bacteria. Thus, our experimental evidence supports that environmental physical constraints can play a selective role in bacterial growth based on cell shape.</p>
},
	keywords = {Bacteria, Cell Shape, Escherichia coli},
	issn = {2041-1723},
	doi = {10.1038/s41467-024-53989-6},
	author = {Sreepadmanabh, M and Ganesh, Meenakshi and Sanjenbam, Pratibha and Kurzthaler, Christina and Agashe, Deepa and Bhattacharjee, Tapomoy}
}
@article {103921,
	title = {A geometric criterion for the optimal spreading of active polymers in porous media.},
	journal = {Nat Commun},
	volume = {12},
	year = {2021},
	month = {2021 Dec 06},
	pages = {7088},
	abstract = {<p>Efficient navigation through disordered, porous environments poses a major challenge for swimming microorganisms and future synthetic cargo-carriers. We perform Brownian dynamics simulations of active stiff polymers undergoing run-reverse dynamics, and so mimic bacterial swimming, in porous media. In accord with experiments of Escherichia coli, the polymer dynamics are characterized by trapping phases interrupted by directed hopping motion through the pores. Our findings show that the spreading of active agents in porous media can be optimized by tuning their run lengths, which we rationalize using a coarse-grained model. More significantly, we discover a geometric criterion for the optimal spreading, which emerges when their run lengths are comparable to the longest straight path available in the porous medium. Our criterion unifies results for porous media with disparate pore sizes and shapes and for run-and-tumble polymers. It thus provides a fundamental principle for optimal transport of active agents in densely-packed biological and environmental settings.</p>
},
	issn = {2041-1723},
	doi = {10.1038/s41467-021-26942-0},
	author = {Kurzthaler, Christina and Mandal, Suvendu and Bhattacharjee, Tapomoy and L{\"o}wen, Hartmut and Datta, Sujit S and Stone, Howard A}
}
