title: Deciphering a survival strategy during the interspecific competition betweenBacillus cereusMSM-S1 andPseudomonassp. MSM-M1.
abstract: Interspecific competition in bacteria governs colony growth dynamics and pattern formation. Here, we demonstrate an interesting phenomenon of interspecific competition betweenBacillus cereusMSM-S1 andPseudomonassp.MSM-M1, where secretion of an inhibitor byPseudomonassp.is used as a strategy for survival. AlthoughB. cereusgrows faster thanPseudomonassp., in the presence ofPseudomonassp. the population ofB. cereusreduces significantly, whereasPseudomonassp. do not show any marked alteration in their population growth. Appearance of a zone of inhibition between growing colonies of two species on nutrient agar prevents the expanding front of the MSM-S1 colony from accessing and depleting nutrients in the region occupied by MSM-M1, thereby aiding the survival of the slower growing MSM-M1 colonies. To support our experimental results, we present simulations, based on a chemotactic model of colony growth dynamics. We demonstrate that the chemical(s) secreted byPseudomonassp. is responsible for the observed inhibition of growth and spatial pattern of theB. cereusMSM-S1 colony. Our experimental results are in excellent agreement with the numerical results and confirm that secreted inhibitors enablePseudomonassp. to survive and coexist in the presence of faster growingB. cereus, in a common niche.
authors.affiliation: Department of Biological Sciences , Indian Institute of Science Education and Research (IISER) Kolkata , Mohanpur 741246 , India.
authors.forename: Brinta
authors.identifier: 0000-0001-7061-3740
authors.initials: B
authors.lastname: Chakraborty
authors.affiliation: Department of Mathematical Sciences , Indian Institute of Science Education and Research (IISER) Kolkata , Mohanpur 741246 , India.
authors.forename: Anish
authors.identifier: 0000-0001-9534-791X
authors.initials: A
authors.lastname: Mallick
authors.affiliation: Department of Biological Sciences , Indian Institute of Science Education and Research (IISER) Kolkata , Mohanpur 741246 , India.
authors.forename: Sumana
authors.initials: S
authors.lastname: Annagiri
authors.affiliation: Department of Physical Sciences , Indian Institute of Science Education and Research (IISER) Kolkata , Mohanpur 741246 , India.
authors.forename: Supratim
authors.identifier: 0000-0001-5294-0561
authors.initials: S
authors.lastname: Sengupta
authors.affiliation: Department of Biological Sciences , Indian Institute of Science Education and Research (IISER) Kolkata , Mohanpur 741246 , India.
authors.forename: Tapas K
authors.identifier: 0000-0001-6482-914X
authors.initials: TK
authors.lastname: Sengupta
keywords: Bacillus; Pseudomonas; interspecific interaction; mathematical model