Study of the Physicochemical Properties of <i>Streptomyces</i> Cell Surface and their Relationship with Soil Salinity of Origin

Physicochemical properties of the bacterial surface are involved in several interfacial phenomena such as microbial adhesion. Ecology Soil salinity is a crucial parameter for the distribution of Streptomyces. The objective of this study is to investigate the impact of NaCl on the hydrophobicity and electron donor/acceptor characteristics of the cell surface of fourteen Streptomyces strains isolated from soils of the Beni Amir region (Morocco) with different salinities. The physicochemical properties of the surface were evaluated using the MATS (microbial adhesion to solvents) method at two concentrations of NaCl (0.1 M and 1.2 M). The results obtained show a significant change from hydrophilic to hydrophobic character. In particular, the Streptomyces lilaceus A53 strain showed the lowest variation (4.21%). On the other hand, the Streptomyces albogriseolus A65 strain presented the greatest variation (86.15%). These changes were observed when the salt concentration increased significantly from 0.1 M to 1.2 M NaCl.The electron donor/acceptor character systematically decreases and even becomes null for the majority of strains. Furthermore, a strong correlation between cell surface hydrophobicity and salinity of the original soil was observed with MATS at 1.2 M NaCl. This study highlights the crucial importance of the NaCl concentration in the modulation of the physicochemical properties of the surface of Streptomyces bacteria.