Orientational order in pseudomonas bacterial colony formation
Abstract
Fresh water Pseudomonas bacteria colonies were grown on glass plates in a biofilm reactor with flow and without flow. In the colony grown with flow, at the center of the colony, bacteria were aligned parallel to each other. At the edges of the colony, the bacteria were disordered in orientation. The colony grown in static water didn't show any order. Bacteria orientational angle distribution and interbacterial separation distance distribution, are presented. The orientational order at the colony centre is understood to be induced by the shear caused by the flow. At the edges, no order existed presumably due to the reversible adhesion phase of the bacteria. The interbacterial closest approach distance was too large to be explained by Derjaquin-landau-Verweey-Overbeek (DLVO) potential.