Abstract:ObjectiveTo understand genetic mutation sites in linezolid (LZD)sensitive and inducible resistant strains of methicillinresistant Staphylococcus aureus(MRSA) using wholegenome sequencing, and realize mutation sites of LZDresistant gene.MethodsMRSAMS4 with explicit genotype and wholegenome sequences was induced by LZD of different concentration gradients, LZDresistant strain MRSAMS4LZD100 was obtained, minimum inhibitory concentration(MIC) was detected, domain V of 23S rRNA and ribosomal proteins L3/L4 gene in MRSAMS4LZD100 were amplified by polymerase chain reaction (PCR), the sequenced products obtained the corresponding mutation site in contrast with the wildtype strain; Illumina PE library was constructed through pairedend sequencing by Illumina HiSeq 2000 technique, and whole genome sequencing was completed based on bioinformatics.ResultsMRASMS4LZD100 strain was induced after 32 passages, MIC of LZD was 96 μg/mL. Sequencing of PCR products indicated the genetic variations were G2447T mutation in multiple copies of domain V of 23S rRNA gene, and Gly113Val mutation in L3 protein respectively; the whole genome of MRSAMS4LZD100 contained 2 744 315 bp, annotation of the whole genome found a total of 2 509 genes, 11 tRNAencoding genes and 2 entire rRNAencoding operons. The data were submitted to the PubMed, and the GeneBank accession number JXMJ00000000 was assigned; a total of 101 SNPs and 6 Small indels were found, 16 of 101SNP mutations occurred in exon, of which the variant proteins with anmino acid sequence alterations included IstB ATP binding domaincontaining protein, clumping factor A, IS1272 transposase and so on; 3 of 6 Small indel mutations occurred in exon, of which the variant proteins with anmino acid sequence alterations included hypothetical protein, 30S ribosomal protein S1, and clumping factor A.ConclusionLZDresistant strain MRSAMS4LZD100 was successfully induced by LZD; beside 23S rRNA V domain and ribosomal L3 protein, the other mutant site exist in this resistant strain, which provide some direction for subsequent study of recessive LZD resistance mechanism.