ABSTRACT
AIM: To develop an applicable vector system and a transformation method for the manipulation of Dietzia spp. METHODS AND RESULTS: The pNV18 Nocardia-E. coli shuttle vector was tested and found to be a replicating plasmid in Dietzia sp. E1. With the use of pNV18, an electroporation method was optimized for the transformation of Dietzia sp. E1, and a transformation efficiency suitable for genetic manipulations was achieved (2·18×10(4) transformants µg(-1) DNA). The method was also applied for the transformation of Dietzia cinnamea, D. maris, D. natronolimnaea and D. psychralcaliphila. CONCLUSIONS: The first applicable vectors and a simple electroporation protocol enabling the manipulation of several Dietzia spp. are presented. SIGNIFICANCE AND IMPACT OF THE STUDY: Dietzia spp. have clinical, industrial and great environmental importance; however, the analysis of the Dietzia genus is currently hampered by the lack of manipulation techniques. The presented basic tools allow the genetic analysis of several Dietzia species, including the human disease-associated Dietzia maris.
Subject(s)
Actinomycetales/genetics , Biotechnology/methods , Electroporation/methods , Genetic Techniques , Actinomycetales/growth & development , Culture Media , Genetic Vectors/genetics , Plasmids/geneticsABSTRACT
The performance of the VITEK 2 System (bioMérieux) version 3.01 software was compared to that of the E-test (AB Biodisk, Solna, Sweden) for antibiotic susceptibility testing of 17 clinical isolates of vancomycin resistant enterococcus (VRE). Antibiotic Susceptibility Testing (AST) by VITEK 2 produced 10 minor (59%) errors, resulting in false phenotypes. Reporting of vancomycin resistance in enterococcal strains has enormous therapeutic and epidemiological consequences. Therefore, at laboratories using automated systems (e.g. VITEK 2) for routine microbiological susceptibility testing data must be confirmed by independent validated methods, e.g. E-test, or microdilution.
Subject(s)
Bacterial Proteins/metabolism , Bacterial Typing Techniques/methods , Carbon-Oxygen Ligases/metabolism , Enterococcus/isolation & purification , Glycopeptides/pharmacology , Microbial Sensitivity Tests/methods , Peptide Synthases/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Typing Techniques/instrumentation , Carbon-Oxygen Ligases/genetics , Enterococcus/classification , Enterococcus/drug effects , Enterococcus/enzymology , Genotype , Gram-Positive Bacterial Infections/microbiology , Humans , Microbial Sensitivity Tests/instrumentation , Peptide Synthases/genetics , Software , Vancomycin ResistanceSubject(s)
Hyperthyroidism/blood , Thyroglobulin/blood , Adult , Female , Humans , Hyperthyroidism/drug therapy , Iodine Isotopes/therapeutic use , Male , Middle Aged , ThyroidectomyABSTRACT
The changes of cell surface hydrophilicity in Bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, pH-shock, phosphate- and carbon-limitation. Although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions. An observed drop in intracellular GTP and/or ATP may be an element of the signal transduction pathway leading to an increase in surface hydrophilicity in response to environmental stresses. Attachment of cells to soil particles under salt stress conditions is strongly influenced by the degS/degU two-component system, which thereby provides a mechanism for the bacteria to escape from the hostile environment.