Subject(s)
Abscess/microbiology , Nocardia Infections/microbiology , Nocardia/isolation & purification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Wound Infection/microbiology , Anti-Bacterial Agents/therapeutic use , Bacterial Typing Techniques/methods , Drug Resistance, Multiple, Bacterial , Female , Humans , Knee , Lincomycin/pharmacology , Middle Aged , Nocardia/drug effects , Nocardia Infections/drug therapy , Nocardia Infections/epidemiology , Pristinamycin/pharmacology , Reunion , Subcutaneous Tissue , Travel , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Wound Infection/drug therapyABSTRACT
Response surface methodology was used to optimize the fermentation conditions for the production of pristinamycin by immobilization of Streptomyces pristinaespiralis F213 in shaking flask cultivation. Seed medium volume, fermentation medium volume and shaking speed of seed culture were found to have significant effects on pristinamycin production by the Plackett-Burman design. The steepest ascent method was adopted to approach the vicinity of optimum space, followed by central composite design for further optimization. A quadratic model was built to fit the pristinamycin production. The optimum conditions were found to be seed medium volume of 29.5 ml, fermentation medium volume of 28.8 ml, and shaking speed of seed culture at 204 rpm. At the optimum conditions, a production of 213 mg/l was obtained, which was in agreement with the maximum predicted pristinamycin yield of 209 mg/l. This is the first report on pristinamycins production by immobilized S. pristinaespiralis using response surface methodology.
Subject(s)
Fermentation , Pristinamycin/biosynthesis , Streptomyces/metabolism , Culture TechniquesABSTRACT
Las infecciones son causa importante de mortalidad en las unidades de cuidados intensivos. Actualmente predominan en Chile las causadas por cocáceas Gram positivas (Staphylococcus aureus resistente a meticilina, Staphylococcus coagulasa negativa y Enterococcus resistente a vancomicina) y en segundo lugar bacilos Gram negativos multiresistentes (Klebsiella pneumoniae). Una indicación antimicrobiana tardía o errada eleva significativamente la letalidad de las infecciones en estas condiciones. La introducción de métodos automatizados de hemocultivos y de técnicas de rápida identificación microbiana permiten emplear antimicrobianos de amplio espectro en una indicación empírica inicial y efectuar rápidos ajustes terapéuticos adecuados a cada situación. Se revisan someramente las bondades y limitaciones de nuevos antimicrobianos potencialmente útiles en estas situaciones: cefepime, carbapenems, nuevas quinolonas, pristinamicina, teicoplanina y linezolid. La indicación de antimicrobianos debe fundamentarse en la epidemiología local de resistencia en las infecciones de origen nosocomial.