Relationship of cell surface hydrophobicity with biofilm formation and growth rate: A study on and .

OBJECTIVES

This study was designed to determine the relationship of and isolates in multispecies biofilms and their individual phenotypic characters in biofilm consortia.

MATERIALS AND METHODS

The subject isolates were recovered from different food samples and identified on the basis of growth on differential and selective media. Tube methods, Congo-red agar method, and scanning electron microscopy (SEM) were used to study biofilms phenotypes. The hydrophobicity of the strains was evaluated by the adhesion to apolar solvent.

RESULTS

The results showed that dominated the pre-biofilm stage. It has been observed that adopted biofilm life much before and . However, after adopting biofilm lifestyle, slowly and gradually, dominated the consortia and dispersed other stakeholders. The subject isolates of produce cis-2-decanoic acid to disperse or inhibit and biofilms. Gas-chromatography and mass spectrometry results showed that cis-2-decanoic was higher in the co-culture condition and increased at late log-phase or at stationary phase. Although majority of were unable to compete with , however, a minor population competed, survived, and persisted in biofilm consortia as small colony variants. The survivors showed higher expression of sigB and sarA genes. showed comparatively higher hydrophobic surface properties.

CONCLUSION

Comparative analysis showed that cell surface hydrophobicity, growth rate, and small colony variants (SCVs) are correlated in biofilm consortia of the and