Investigating SLH Domain in Swarming Motility

To investigate the role of the SLH-Gly29 residue in SLH domain-carrying proteins of Gram-positive bacteria within a biological context, an assay based on P. alvei CCM 2051^T swarming ability on agar plates was used^{49 (link)}. To test the swarming motility of P. alvei ΔslhA and P. alvei ΔslhA_comp strains provided with plasmid-encoded slhA and slhA/G1224A/G1293A in comparison to P. alvei wt, cells were grown overnight (OD₆₀₀ ~2.0) and 5 µL of each culture were applied on 1% (semi-solid) LB agar plates. P. alvei wt and P. alvei ΔslhA cells were incubated at 37 °C for 24 h, whereas complemented, pEXALV vector-based P. alvei strains were incubated at 37 °C for 48 h. Images were taken using an EPSON PERFECTION V750 PRO scanner. The experiments were repeated at least in triplicates.