LapF and Its Regulation by Fis Affect the Cell Surface Hydrophobicity of Pseudomonas putida

Abstract

The ability of bacteria to regulate cell surface hydrophobicity is important for the adaptation to different environmental conditions. The hydrophobicity of cell surface can be determined by several factors, including outer membrane and surface proteins. In this study, we report that an adhesin LapF influences cell surface hydrophobicity of Pseudomonas putida. Cells lacking LapF are less hydrophobic than wild-type cells in stationary growth phase. Moreover, the overexpression of the global regulator Fis decreases surface hydrophobicity by repressing the expression of lapF. Flow cytometry analysis revealed that bacteria producing LapF are more viable when confronted with methanol (a hydrophilic compound) but are more susceptible to 1-octanol (a hydrophobic compound). Thus, these results revealed that LapF is the hydrophobicity factor for the cell surface of P. putida.

Mutation of the Carboxy-Terminal Processing Protease in Acinetobacter baumannii Affects Motility, Leads to Loss of Membrane Integrity, and Reduces Virulence

“…One of the functions of outer membrane proteins is to maintain outer membrane integrity, and our result shows membrane damage of MR14 strain (Figure 6). Hydrophobicity of the cell surface is also reported to be influenced by outer membrane and surface proteins and LPS [29]. Additionally, when we observed the cell pellet pattern after centrifugation, we found that MR14 had relatively longer cell pellet patterns, as described previously [30], and the pellet forms a clump that cannot be easily resuspended in either ddH2O, PBS, or LB medium (data not shown).…”

The promoter region of lapA and its transcriptional regulation by Fis in Pseudomonas putida

“…LapA seems to be the most important biofilm factor [ 7 , 11 ] as no conditions efficiently rescuing the lapA mutant’s biofilm formation defect have been reported [ 5 , 11 , 12 ]. The second large extracellular protein, LapF, is the cell surface hydrophobicity factor [ 13 ] and probably contributes to cell-cell attachment by regulating cell hydrophobicity [ 9 ]. However, LapF seems to be an important factor for biofilm formation only when P .…”

Genetic Cell-Surface Modification for Optimized Foam Fractionation

“…An interesting finding is the low foam adhesion by P. putida S12 and P. putida DOT-T1E. While for P. putida, it is known that the adhesin LapF increases CSH (Lahesaare et al, 2016), no homolog of lapF was found on the respective genomes of these strains. However, at least in Germany, all P. putida strains except KT2440 are of biosafety level 2 (Nelson et al, 2002;ZKBS, 2012), a true challenge for the development of new bioprocesses, strongly advocating the usage of P. putida KT2440.…”

“…In Pseudomonas, several cell surface molecules contributing to changes in CSH have been identified, such as the lipopolysaccharide layer (LPS) (Makin and Beveridge, 1996;Kobayashi et al, 2000). Pseudomonas putida's large adhesive protein A (Lap A) and particularly F (LapF) increase cell surface hydrophobicity (Lahesaare et al, 2016). In P. putida KT2440, LapA is the largest surface protein and required for cell-to-cell as well as for abiotic surface interactions (Hinsa et al, 2003;Fuqua, 2010).…”