hide
Free keywords:
biochemical pathway
fucoidan
metabolism
polysaccharides
regulation
structurally coloured bacteria
Bacteria
Cells
Color
Cytology
Nutrients
Bacterial colonies
Biochemical process
Colouration
Flavobacterium
Fucoidans
Nano scale
Structural color
Structurally colored bacteria
carrageenan
fucoidin
polysaccharide
Article
bacterial growth
bacterium colony
controlled study
crystal structure
diffraction
extracellular matrix
light intensity
microscopy
nonhuman
optics
refraction index
transmission electron microscopy
wild type
bacterium
Abstract:
The brightest colours in nature often originate from the interaction of light with materials structured at the nanoscale. Different organisms produce such coloration with a wide variety of materials and architectures. In the case of bacterial colonies, structural colours stem for the periodic organization of the cells within the colony, and while considerable efforts have been spent on elucidating the mechanisms responsible for such coloration, the biochemical processes determining the development of this effect have not been explored. Here, we study the influence of nutrients on the organization of cells from the structurally coloured bacteria Flavobacterium strain IR1. By analysing the optical properties of the colonies grown with and without specific polysaccharides, we found that the highly ordered organization of the cells can be altered by the presence of fucoidans. Additionally, by comparing the organization of the wild-type strain with mutants grown in different nutrient conditions, we deduced that this regulation of cell ordering is linked to a specific region of the IR1 chromosome. This region encodes a mechanism for the uptake and metabolism of polysaccharides, including a polysaccharide utilization locus (PUL operon) that appears specific to fucoidan, providing new insight into the biochemical pathways regulating structural colour in bacteria. ©
