PROIMI   05436
PLANTA PILOTO DE PROCESOS INDUSTRIALES MICROBIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Evidence of andrimid production by a psychrotolerant Serratia proteamaculans strain
Autor/es:
SANCHEZ L. A,; GONZALEZ-SIERRA, M; DELGADO O.D.
Lugar:
Mar del Plata
Reunión:
Congreso; X Congreso de Microbiologia General SAMIGE; 2012
Institución organizadora:
Sociedad Argentina de Microbiologia General (SAMIGE)
Resumen:
Key factors such as frequent and inappropriate use of antibiotic causing increased bacterial resistance to those commonly used, in addition to an irregular emergence generated from a detriment of pharmaceutical companies involved in drugs discovery makes the development of new antibiotics is an increasing worldwide problem and a constant challenge. The necessity to reduce additives in the food industry has triggered the search for natural antimicrobial substances produced by microorganisms from different sources with the aim to preserve processed foods by inhibiting microorganisms associated with food-borne illness. Most antibiotics emerged from search programs (screening) in natural sources using microbiological tools which include the isolation of new microorganisms, modification of well-known producer microorganisms or metabolic engineering of fermentation processes. This work involves structure elucidation and characterization of an antimicrobial produced by a psychrotolerant Serratia proteamaculans 136 strain. The antibiotic peptide was produced at low temperatures (4°C) and strong activity was revealed against both pathogenic and non-pathogenic bacteria at different CIM values. The effect over ultra-structure of sensitive bacteria was observed by transmission electron microscopy at different inhibition stages, resulting in the presence of pores in the bacterial surface and loss of cytoplasmic content by disruption of the cell membrane. Andrimid structure was confirmed by combining LC MS/MS and NMR approaches. The parental ion (479.2 m/z) showed six product ions with 121, 195, 226, 239, 268, 343 m/z and differences in relative abundance of each ion type. To state the antimicrobial sum formula, mass data in addition to natural isotopes distribution with their relative intensities were evaluated under SIRIUS software in [M + H]+ form, using an efficient deconvolution algorithm in order to obtain the possible sum formula. This study constitutes the first report of cold-active andrimid production by a S. proteamaculans strain. The possible horizontally transference among Pantoea, Pseudomonas and Serratia genera is discussed. The work also highlights cold environments as a suitable source of microorganisms with the ability to produce cold-active biomolecules of biotechnological interest.