Transition of a solitary to a biofilm community life style in bacteria: a survival strategy with division of labour

Abstract

Multicellularity is associated with higher eukaryotes having an organized division of labour and a coordinated action of different organs composed of multiple cell types. This division of different cell types and organizations to form a multicellular structure by developmental programming is a key to the multitasking of complex traits that enable higher eukaryotes to cope with fluctuating environmental conditions. Microbes such as bacteria, on the other hand, are unicellular and have flourished in diverse environmental conditions for a much longer time than eukaryotes in evolutionary history. In this review, we will focus on different strategies and functions exhibited by microbes that enable them to adapt to changes in lifestyle associated with transitioning from a unicellular solitary state to a complex community architecture known as a biofilm. We will also discuss various environmental stimuli and signaling processes which bacteria utilize to coordinate their social traits and enable themselves to form complex multicellular-like biofilm structures, and the division of labour operative within such communities driving their diverse social traits. We will also discuss here recent studies from our laboratory using a plant-associated bacterial pathogen as a model organism to elucidate the mechanism of bacterial cell-cell communication and the transition of a bacterial community to a multicellular-like structure driven by the complex regulation of traits influenced by cell density, as well as environmental sensing such as chemotaxis and nutrient availability. These studies are shedding important insights into bacterial developmental transitions and will help us to understand community cooperation and conflict using bacterial cell-cell communication as a model system.

Bacterial survival on inanimate surfaces: a field study

“…Secondly, we did not check for the degree of biofilm formation although this may also influence the ability to survive on an inanimate surface [ 34 ]. For example, A. baumannii may form strong biofilms on stainless steel surfaces and bacteria within this biofilm are significantly more resistant to environmental noxa than are their planktonic counterparts [ 35 ].…”

The diffusible signal factor synthase, RpfF, in Xanthomonas oryzae pv. oryzae is required for the maintenance of membrane integrity and virulence

“…The DSF regulatory system has been extensively studied over the last few decades in many xanthomonads and has been implicated in (An et al, 2020;Büttner & Bonas, 2010;Chatterjee & Sonti, 2002;Chatterjee et al, 2020;Deng et al, 2016;Guo et al, 2012;He et al, 2010;Kakkar et al, 2015;Rai et al, 2012Rai et al, , 2015Ryan et al, 2015).…”

“…In bacteria, cell population density sensing plays an important role in the regulation of several social behaviours such as secondary metabolite production, antibiotic resistance, lifestyle transition, virulence factor secretion, and response to environmental stresses (Bronesky et al, 2016 ; Chatterjee et al, 2020 ; Pena et al, 2019 ). To do this, bacteria use a cell–cell communication process called quorum sensing (QS), which integrates environmental cues, cell density, and cell history by coordinating multiple signalling pathways (LaSarre & Federle, 2013 ; Lee & Zhang, 2015 ; Moradali et al, 2017 ; Moreno‐Gàmez et al, 2017 ; Rutherford & Bassler, 2012 ).…”

“…This enables bacteria to synchronize the expression of energetically expensive biological processes as a collective only when the impact of those processes on the environment or a host will be maximized (Pena et al, 2019 ). QS relies on the production, release, accumulation, and population‐wide detection of extracellular small diffusible signal molecules called autoinducers (Chatterjee et al, 2020 ; Eickhoff & Bassler, 2018 ).…”

Contact-Dependent Growth Inhibition in Bacteria: Do Not Get Too Close!

“…Like most living organisms, the inhabitants of the microworld (including bacteria) prefer to form mono-species or more complex multi-species communities. In these communities, bacteria of one species can collaborate against other species, distribute responsibilities, and even sacrifice a part of the population for the survival of the species due to changing environmental conditions [1][2][3][4][5]. One of the ways a bacterial cell can adapt to its environment is the production of effector molecules ("toxins"), some of which are designed to interact with the host cells, while others are aimed at regulating relationships with other inhabitants of the microbiome.…”