Brief Report: Ribosomal Proteins Mutations of Staphylococcus haemolyticus Causing Linezolid Resistance in Egyptian ICU Patients

Abstract

Linezolid resistance has since emerged gained a lot of attention worldwide as linezolid is considered one of the last resort antibiotics against multiple-drug resistant bacterial strains, yet in Egypt, little is known about the situation. As various linezolid resistance mechanisms have been identified in staphylococci, we investigated the molecular characteristics of staphylococci showing reduced
susceptibility to Linezolid at Kasr-El-Eini Teaching Hospital. Thirty isolates were examined by disc diffusion method. Of the 30 isolates, two were confirmed as linezolid resistant and screened for the presence of mutations by sequencing the ribosomal proteins (L3, L4, and L22). Strain SZ-2 harbored a L3 M156T. H146P and V154L amino acids alternations, while in strain SZ-7, a L3 R138V, R144V,
G152D and V154L mutations were detected. Novel mutations M105L and E191R in L4 protein were detected in strain SZ-2 and strain SZ-2, respectively. No isolates contained L22 protein alterations.