title: DnaK and GroEL are induced in response to antibiotic and heat shock in Acinetobacter baumannii.
abstract: We studied the expression of DnaK and GroEL in Acinetobacter baumannii cells (strains ATCC 19606 and RS4) under stress caused by heat shock or antibiotics. A Western blot assay showed that DnaK and GroEL levels increased transiently more than 2-fold after exposure of bacterial cells to heat shock for 20 min at 50 degrees C. Heat induction of DnaK and GroEL was blocked completely when an inhibitor of transcription, rifampicin, was added 1 min before a temperature upshift to 50 degrees C, suggesting that the induction of these chaperones depends on transcription. A. baumannii cells pretreated at 45 degrees C for 30 min were better able to survive at 50 degrees C for 60 min than cells pretreated at 37 degrees C, indicating that A. baumannii is able to acquire thermotolerance. DnaK and GroEL were successfully induced in cells pre-incubated with a subinhibitory concentration of streptomycin. Moreover, bacterial cells pretreated for 30 min at 45 degrees C were better able to survive streptomycin exposure than cells pretreated at physiological temperatures. DnaK expression was upregulated in a multidrug-resistant strain of A. baumannii (RS4) in the presence of different antimicrobials (ampicillin+sulbactam, cefepime, meropenem and sulphamethoxazole+trimethoprim). This study is to the best of our knowledge the first to show that A. baumannii DnaK and GroEL could play an important role in the stress response induced by antibiotics.
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Karen
authors.initials: K
authors.lastname: Cardoso
authors.affiliation: Laboratório de Microbiologia Clínica, Hospital Universitário do Oeste do Paraná, Cascavel, PR 85806-470, Brazil.
authors.forename: Rinaldo Ferreira
authors.initials: RF
authors.lastname: Gandra
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Edirlene Sara
authors.initials: ES
authors.lastname: Wisniewski
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Clarice Aoki
authors.initials: CA
authors.lastname: Osaku
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Marina Kimiko
authors.initials: MK
authors.lastname: Kadowaki
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Vicente
authors.initials: V
authors.lastname: Felipach-Neto
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Leandro Fávero Aby-Ázar
authors.initials: LFA
authors.lastname: Haus
authors.affiliation: Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Cascavel, PR 85814-110, Brazil.
authors.forename: Rita de Cássia Garcia
authors.initials: RCG
authors.lastname: Simão
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018834:Chaperonin 60 / Q000235:genetics / Q000378:metabolism*; D024901:Drug Resistance, Multiple, Bacterial / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D006358:Hot Temperature
chemical_list: D000900:Anti-Bacterial Agents; D018834:Chaperonin 60; D000251:Adenosine Triphosphatases