Mass Spectrometric Characterization of Oligomers in Pseudomonas aeruginosa Azurin Solutions

0359153 - ÚFCH JH 2012 RIV US eng J - Journal Article
Sokolová, L. - Williamson, H. - Sýkora, Jan - Hof, Martin - Gray, H. B. - Brutschy, B. - Vlček, Antonín
Mass Spectrometric Characterization of Oligomers in Pseudomonas aeruginosa Azurin Solutions.
Journal of Physical Chemistry B. Roč. 115, č. 16 (2011), s. 4790-4800. ISSN 1520-6106. E-ISSN 1520-5207
R&D Projects: GA MŠMT(CZ) ME10124; GA MŠMT(CZ) LC06063
Institutional research plan: CEZ:AV0Z40400503
Keywords : mass spectrometry * oligomers * pseudomonas aeruginosa azurin solutions
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 3.696, year: 2011

We have employed laser-induced liquid bead ion desorption mass spectroscopy (LILBID MS) to study the solution behavior of Pseudomonas aeruginosa azurin as well as two mutants and corresponding Re-labeled derivatives containing a Re(CO)3(4,7-dimethyl-1,10-phenanthroline)+ chromophore appended to a surface histidine. LILBID spectra show broad oligomer distributions whose particular patterns depend on the solution composition (pure H2O, 20−30 mM NaCl, 20 and 50 mM NaPi or NH4Pi at pH = 7). The distribution maximum shifts to smaller oligomers upon decreasing the azurin concentration and increasing the buffer concentration. Oligomerization is less extensive for native azurin than its mutants. The oligomerization propensities of unlabeled and Re-labeled proteins are generally comparable, and only Re126 shows some preference for the dimer that persists even in highly diluted solutions.
Permanent Link: http://hdl.handle.net/11104/0006430