Biofilm formation onto starch fibres byBacillus subtilisgoverns its successful adaptation to chickpea milk

Beneficial biofilms may confer effective adaptation to food matrices that assist bacteria in enduring hostile environmental conditions. The matrices, for instance, dietary fibres of various food products, might serve as a natural scaffold for bacterial cells to adhere and grow as biofilms. Here, we report on a unique interaction ofBacillus subtiliscells with the resistant starch fibresof chickpea milk (CPM), herein CPM fibres, along with the production of a reddish-pink pigment. Genetic analysis identified the pigment as pulcherrimin, and also revealed the involvement of Spo0A/SinI pathway in modulating the observed phenotypes. Besides, through successful colonization of the CPM fibres, the wild-type cells ofB. subtilisdisplayed enhanced survivability and resilience to environmental stress, such as heat andin vitrogastrointestinal treatments. In total, we infer that the biofilm formation on CPM fibres is an adaptation response ofB. subtilisfor strategic survival.

Automated summary

The study demonstrates that Bacillus subtilis forms a beneficial biofilm on chickpea milk fibres, producing pulcherrimin pigment, which enhances survivability and resilience to environmental stress through the Spo0A/SinI pathway. This biofilm formation is seen as an adaptation response for strategic survival.