The cyanotrophic bacterium Pseudomonas pseudoalcaligenes CECT5344 responds to cyanide by defence mechanisms against iron deprivation, oxidative damage and nitrogen stress.
Two-dimensional (2-D) electrophoresis approach has been used to test protein expression changes in response to cyanide in the alkaliphilic bacterium Pseudomonas pseudoalcaligenes CECT5344. This is a cyanide-assimilating strain which also grows in media containing cyanide-enriched effluent from the jewellery industry. The bacterium efficiently uses this residue as the sole nitrogen source for aerobic growth under alkaline pH with negligible nitrogen losses as HCN. Cell-free extracts isolated from P. pseudoalcaligenes grown with a jewellery residue, free cyanide or ammonium chloride as nitrogen source were subjected to 2-D electrophoresis and the spot patterns were examined to determine differential protein expression. Electrophoretic plates exhibiting an average of 1000 spots showed significant differences in the expression of about 44 proteins depending on the nitrogen source. Some of these protein spots were analysed by Matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Characterization of five of these proteins reveals that cyanide shock induces proteins related to iron acquisition, regulation of nitrogen assimilation pathways and oxidative stress repairing and protection.
Luque-Almagro
Victor M
VM
Departamento de Bioquímica y Biología Molecular, Campus de Rabanales, Edificio Severo Ochoa, Universidad de Córdoba, 14071 Córdoba, Spain.
Huertas
María J
MJ
Roldán
M Dolores
MD
Moreno-Vivián
Comrado
C
Martínez-Luque
Manuel
M
Blasco
Rafael
R
Castillo
Francisco
F
D003486:Cyanides / Q000378:metabolism*; D003674:Defense Mechanisms; D004591:Electrophoresis, Polyacrylamide Gel; D000090463:Iron Deficiencies; D009584:Nitrogen / Q000378:metabolism*; D018384:Oxidative Stress / Q000502:physiology*; D044205:Pseudomonas pseudoalcaligenes / Q000378:metabolism* / Q000502:physiology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D003486:Cyanides; D009584:Nitrogen