title: Novel nonsense mutation in the katA gene of a catalase-negative Staphylococcus aureus strain.
abstract: We report the first description of a rare catalase-negative strain of Staphylococcus aureus in Chile. This new variant was isolated from blood and synovial tissue samples of a pediatric patient. Sequencing analysis revealed that this catalase-negative strain is related to ST10 strain, which has earlier been described in relation to S. aureus carriers. Interestingly, sequence analysis of the catalase gene katA revealed presence of a novel nonsense mutation that causes premature translational truncation of the C-terminus of the enzyme leading to a loss of 222 amino acids. Our study suggests that loss of catalase activity in this rare catalase-negative Chilean strain is due to this novel nonsense mutation in the katA gene, which truncates the enzyme to just 283 amino acids.
authors.affiliation: Molecular Genetics Subdepartment, Chile.
authors.forename: Jaime
authors.initials: J
authors.lastname: Lagos
authors.affiliation: Infection Disease Subdepartment, Chile.
authors.forename: Pedro
authors.initials: P
authors.lastname: Alarcón
authors.affiliation: Public Health Institute, Clinical Laboratory, Hospital Roberto del Río, Chile.
authors.forename: Dona
authors.initials: D
authors.lastname: Benadof
authors.affiliation: Molecular Genetics Subdepartment, Chile.
authors.forename: Soledad
authors.initials: S
authors.lastname: Ulloa
authors.affiliation: Virology Subdepartment, Chile.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Fasce
authors.affiliation: Molecular Genetics Subdepartment, Chile.
authors.forename: Javier
authors.initials: J
authors.lastname: Tognarelli
authors.affiliation: Molecular Genetics Subdepartment, Chile.
authors.forename: Carolina
authors.initials: C
authors.lastname: Aguayo
authors.affiliation: Infection Disease Subdepartment, Chile.
authors.forename: Pamela
authors.initials: P
authors.lastname: Araya
authors.affiliation: Molecular Genetics Subdepartment, Chile.
authors.forename: Bárbara
authors.initials: B
authors.lastname: Parra
authors.affiliation: Molecular Genetics Subdepartment, Chile.
authors.forename: Berta
authors.initials: B
authors.lastname: Olivares
authors.affiliation: Infection Disease Subdepartment, Chile.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Hormazábal
authors.affiliation: Molecular Genetics Subdepartment, Chile. Electronic address: jofernand@gmail.com.
authors.forename: Jorge
authors.initials: J
authors.lastname: Fernández
mesh_terms: D001168:Arthritis / Q000382:microbiology; D016470:Bacteremia / Q000382:microbiology; D002374:Catalase / Q000235:genetics* / Q000378:metabolism*; D002675:Child, Preschool; D002677:Chile; D018389:Codon, Nonsense; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005838:Genotype; D006801:Humans; D017422:Sequence Analysis, DNA; D013203:Staphylococcal Infections / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics*
chemical_list: D018389:Codon, Nonsense; D004269:DNA, Bacterial; D002374:Catalase
keywords: Catalase gene; Catalase-negative; Staphylococcus aureus; katA