Gold nanoparticles (AuNPs) have been utilized in various biomedical applications including diagnostics and drug delivery. However, the cellular and metabolic responses of cells to these particles remain poorly characterized. In this study, we used bacteria ( and ) and a fungus () as model organisms to investigate the cellular and metabolic effects of exposure to different concentrations of citrate-capped spherical AuNPs with diameters of 5 and 10 nm.
View Article and Find Full Text PDFXenorhabdus nematophila secretes insecticidal proteins to kill its larval prey. We have isolated an approximately 58-kDa GroEL homolog, secreted in the culture medium through outer membrane vesicles. The protein was orally insecticidal to the major crop pest Helicoverpa armigera with an LC50 of approximately 3.
View Article and Find Full Text PDFWe have purified a fimbrial shaft protein (MrxA) of Xenorhabdus nematophila. The soluble monomeric protein lysed larval hemocytes of Helicoverpa armigera. Osmotic protection of the cells with polyethylene glycol suggested that the 17-kDa MrxA subunit makes pores in the target cell membrane.
View Article and Find Full Text PDFBiochem Biophys Res Commun
April 2004
Extracellular glutamine synthetase (GS) is one of the prominent proteins secreted by pathogenic mycobacteria such as Mycobacterium tuberculosis and Mycobacterium bovis. Non-pathogenic species like Mycobacterium smegmatis and Mycobacterium phlei do not secrete this protein. GS has been proposed to play an indispensable role in intracellular survival of pathogenic mycobacteria.
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