Influence of attached growth on the performance of Pseudomonas fluorescens grown on fluoroacetate as the sole organic substrate Running title: Influence of attached growth on P. fluorescens

The UCD community has made this article openly available. Please share how this access benefits you. Your story matters! (@ucd_oa) Some rights reserved. For more information, please see the item record link above. Abstract 1 2 Comparisons between the physiological properties of Pseudomonas fluorescens biofilm cells 3 grown in a tubular biofilm reactor and planktonic cells grown in a chemostat were performed. 4 Fluoroacetate was the sole carbon source for all experiments. The performance of cells was 5 assessed using cell cycle kinetics and by determining specific fluoroacetate utilization rates. 6 Cell cycle kinetics were studied by flow cytometry in conjunction with the fluorescent stain 7 propidium iodide. Determination of the DNA content of planktonic and biofilm cultures 8 showed little difference between the two modes of growth. Cultures with comparable specific 9 glycolate utilization rates had similar percentage of cells in the B phase of the cell cycle 10 indicating similar growth rates. Specific fluoroacetate utilization rates showed the 11 performance of planktonic cells to be superior to biofilm cells with more fluoroacetate 12 utilized per cell at similar specific fluoroacetate loading rates. A consequence of this 13 decreased biofilm performance was the accumulation of glycolate in the effluent of biofilm 14 cultures. This accumulation of glycolate was not observed in the effluent of planktonic 15 cultures. Spatial stratification of oxygen within the biofilm was identified as a possible 16 explanation for the overflow metabolism of glycolate and the decreased performance of the 17 biofilm cells.